Cost-effective method for producing powder

Abstract

To disclose a method for producing fine particulate materials by atomization (CA).SOLUTION: A method of this invention is suitable for obtaining fine spherical powders having an outstanding morphological quality and a very low or no content of nonspherical particles and internal voids. A suitable cost-effective method is also disclosed for producing powders of a metal, alloy, intermetallic compound, metal-based composite material, or metal-like material in large batches on an industrial scale. An atomization technique can be extended beyond centrifugal atomization using rotor technology.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present invention relates to a method for producing metal-based alloy powders or particulate materials using centrifugal atomization, primarily using rotating disk atomization technology. The invention is designed to produce rapidly solidified metal powders. In addition, the invention allows the production of fine or very fine, highly spherical powders in narrow particle size distributions in a cost-effective manner. Furthermore, the invention allows the production of spherical powders or particulate materials with very little or no sausage-shaped, teardrop-shaped, ellipsoidal, broken spheres, other non-spherical particles, intra-sphere voids, or hollow spheres, which have been unavoidable in the centrifugal atomization of very fine powders. The present invention also allows the production of alloy powders that are difficult to handle, such as alloys with very high melting points or elements that react strongly with oxygen, using atomization. [Background technology]

[0002] overview Atomization is the primary method for producing pre-alloyed powders from low melting point solder alloys, aluminum, copper, iron, low alloy steels, stainless steels, tool steels, titanium, superalloys, etc. Although there are various production methods, the atomization process and technology, especially water and gas atomization, have remained the primary method in the production of high melting point metal powders. Although both techniques are relatively easy to implement, they are energy inefficient in addition to adding widely known characteristics of the produced powders. These characteristics include, for example, irregular shape, low surface quality, relatively high internal porosity, and relatively wide particle size distribution (high geometric standard deviation σ_”g”, about 2.0-2.3). These techniques also pose additional challenges when trying to obtain powders containing elements that react strongly with oxygen, such as lithium and scandium. Atomization with high purity gases is associated with increased costs and further losses of these reactive elements. Lithium is expensive, and scandium is even more expensive. For aluminum alloys containing about 0.5 wt% scandium, it is usually necessary to add four times as much scandium to the melt pool. This means that the loss of this alloying element can increase the cost of the metal powder by as much as 60 euros / kg. In the case of lithium, magnesium-lithium alloys with lithium contents above 10 wt% are almost impossible to process. On the other hand, under certain process conditions, other techniques such as centrifugal atomization (CA) show a higher energy efficiency. However, such processes are often more technically complex than the aforementioned techniques. And, if the process is controlled, it is possible to obtain high-quality powders with a low percentage of non-spherical irregular particles, which increase when trying to produce smaller particles and are often impossible to separate, especially when very fine powders are involved. Despite being a small percentage, the inclusion of these non-spherical particles compromises the overall usefulness of the powder in many applications.

[0003] There are two main types of centrifugal atomization: rotating electrode and rotating disk. Centrifugal atomization using a rotating electrode consists of rotating an electrode of the metal, alloy, intermetallic compound or metal matrix composite to be produced at very high speed and melting it at its tip using a high power laser, electron beam or focused plasma. Centrifugal atomization of molten metal by a rotor is a physical method of producing powder from liquid metal, in which a liquid stream of molten metal (also called liquid metal) is passed over a rotating disk or other object, where it is broken down and dispersed into extremely fine powder by the action of centrifugal force, and then solidified by contact with the air.

[0004] Rotating electrodes using plasma, electron beam and laser melting are well-established technologies for the production of very high quality spherical powders, but existing solutions are very costly.

[0005] Centrifugal molten atomization of metal by a rotating body is established for the production of not very fine, low melting point solder alloys.

[0006] In PCT / EP2015 / 051632, a method of centrifugal atomization using a rotating disk is described that can be used successfully to atomize fine powders of some difficult alloys, as well as those and other alloys, but the application does not describe any specific measures to eliminate the fraction of non-spherical particles that occurs in all centrifugal atomization methods unless very specific measures are taken to counteract this effect.

[0007] Traditionally, tool steel powders were produced by gas or water atomization. Generally, water atomized tool steel powders exhibit irregular particles and are suitable for die compaction and sintering with higher theoretical density. Gas atomized tool steel powders have spherical or nearly spherical particles with high bulk density, but may require consolidation by hot or cold isostatic pressing. The importance of powder metallurgy of tool steels is mainly based on the uniform structure obtained compared to forged or conventional products and the higher homogeneity of their chemical composition. This situation leads, for example, to superior toughness values ​​and reduced distortion during heat treatment, which in turn leads to improved tool life. Recently, systems have also been developed using the direct reduction of titanium oxide powders, but the same is true for most metal alloy powders.

[0008] The general concept of centrifugal atomization using rotating bodies was developed a long time ago, and many different scientific teams have worked on this technology at different places and times. It is therefore generally accepted in the scientific community that the technology has unavoidable physical limitations. These limitations have largely prevented its expansion beyond its current use for the production of rather coarse, low-melting metal or metal-like powders.

[0009] The two main limitations of the technology, which is based on well-studied physical principles of operation, are the exponential relationship between the achievable average particle size and the rotation speed of the rotor that disperses the liquid. That is, at low rotation speeds, small rotation speed increments result in a large decrease in the average particle size of the atomized powder. However, this effect becomes smaller until very high rotation speed increments are required for an irrelevant particle size reduction (Figure 1). In fact, considering the rotation speeds achievable within the next 20 years, there is a theoretically achievable minimum size with this technology, which depends on the chemical nature of the powder produced. In fact, if the achievable rotation speeds in the next 20 years were to be ten times higher than expected, the minimum achievable average particle size would remain almost unchanged with this technology.

[0010] The average particle size and the amplitude of the particle size distribution are very important, because they make the difference between a rare technology that is evaluated at a scientific conference and a technology that has the potential for industrial application. This is because these two factors have a very direct impact on the production costs of the powder produced. Fine or very fine powders with a large average particle size and a very wide particle size distribution are obtained. However, in that case only a small part of the powder produced is micronized, which is very costly and only suitable for scientific research. On the other hand, technologies that provide a fine or very fine average particle size and a narrow particle size distribution lead to the micronization of a large part of the powder to be micronized.

[0011] Another major limitation of the technology concerns the production of high melting point alloys. In fact, powders of alloys with melting points above 700 K have been produced on a laboratory scale, knowing that they cannot be scaled on an industrial scale. Powders with melting points above 1300 K and even Ni-, Ti- and Fe-based alloys have been atomized on a laboratory scale. However, in this case, only very small amounts can be atomized on a laboratory scale. This means that scaling up the technology to an industrial scale is unrealistic. It is known that attempts to increase the production batches result in a deterioration of the morphological quality of the powders obtained. Alloys containing elements with a high reactivity towards oxygen are even more difficult to handle and even more unrealistic.

[0012] In summary, due to the twofold limitation of centrifugal atomization using a rotating body, there are two problems that the present invention aims to solve: The possibility of micronization and It is possible to produce highly reactive and difficult-to-make alloys.

[0013] The technical effect is expected in both cases to obtain spherical powders or particulate materials with very little or no intraspherical voids or hollow spheres, which are unavoidable in the centrifugal atomization of sausage-shaped, teardrop-shaped or other non-spherical particles, extremely fine powders. One of the major challenges is to achieve this at practically relevant costs and without any known disruption of the morphological quality. The inventors have found that in some applications the invention is suitable for obtaining surprisingly narrow particle size distributions of fine, spherical powders with exceptional morphological quality. Furthermore, the invention is suitable for producing powders with a higher metallic tone, which is suitable for several applications by the end user. The disclosed method for producing powders is also suitable for producing particulate materials with an essentially complete absence of particles containing a thick oxide crust and with exceptionally low or no internal voids. The inventors have also found that in some applications the method disclosed herein makes it possible to produce fine powders at surprisingly lower costs than those observed with the methods disclosed in the prior art. The flowability of powders is directly related to the interparticle friction. The disclosed method is also suitable for obtaining fine and spherical powder size distributions with excellent flow properties. Moreover, the level of microsegregation in the atomized powder is surprisingly lower than expected when following the present invention.

[0014] The inventors found that the existing models are incomplete, as is usually the case for average particle sizes achieved by centrifugal atomization of large lots, but, very surprisingly, they ignore a combination of variables that seems more relevant than almost all the other variables considered in the models. The inventors found a way to obtain a much finer powder than PCT / EP2015 / 051632. More importantly, the powder is practically free of non-spherical particles and void powder, which is very important to limit given the difficulties in separating small amounts of fine powder and the obstacles in certain applications. After all rational selections, tests were performed with random combinations of process variables. I almost gave up, but fortunately, the tests gave me a combination of variables that solved the problem.

[0015] Background technology In the following paragraphs, we briefly review the current state of atomization technology and relevant aspects, although there are excellent comprehensive literature reviews on the subject [Metal Powder Industry, ISBN-13: 978-187895415, 1992; Oxford University Press, ISBN-13: 978-0198562580, 1994; ASM International, ISBN-13: 978-0871703873, 1998; Metal Powder Industry, ISBN-13: 978-0976205715, 2005]. Melt atomization is the transformation of a large volume of liquid into a spray of droplets in the surrounding atmosphere. This volume of liquid is formed by melting a substance that is solid under normal conditions of pressure and temperature (20°C and 1 atm). Then, after an atomization stage and cooling, the final product is a powder. Metal atomization is the most common method that can produce metal powders with a wide range of compositions and particle sizes. Centrifugal atomization of melts using a rotating medium (also called spinning disk, spinning cup, or spin atomization) is defined as a physical method of obtaining powder by passing a liquid stream of molten metal through a rotating disk (SDA) or other rotating medium, dispersing the liquid into droplets, flakes, dust, or other droplets using the centrifugal force of the rotating medium, which solidify on contact with the air [ASM International, ISBN-13: 978-0871703873, pp. 35-52, 1998].

[0016] In Figure 1, it can be seen that the achievable average particle size depends on the material being processed and especially on the rotation speed of the atomizer, but the dependence on the speed is exponential and shows a saturation effect. The height of the hydraulic pressure, the amount of material being processed per unit time, and other variables also play a role. However, their contribution to the particle size is almost negligible compared to the two variables shown (nature of the atomizing liquid and rotation speed), especially if they are kept at a level that is meaningful for industrial production. From this figure, it is clear that the cost-effectiveness of producing fine and extremely fine powders by centrifugal atomization with a rotating body is negligible. Also, centrifugal atomization of spherical powders always contains small to medium amounts of non-spherical powders, but in the case of fine, medium and coarse powders, they can be separated and this is not of great importance because it only has a negative effect on the yield. However, in the case of extremely fine powders, separation becomes very difficult or impossible. Since such extremely fine powders cannot theoretically be achieved by centrifugal atomization (see Figure 1), this fraction has not been given much thought and is hardly mentioned. US 2002 / 0094297 describes small laboratory batches of powder. The disks are cooled directly with water (quenched disks) and the minimum achievable particle size is 177 microns. It is not possible to obtain spherical powders and there is no mention of how to remove non-spherical particles such as sausages, satellites, splats, etc., or how to remove voids or hollow particles in the particles. Among other things, there is no mention of how to control the pressure depending on the rotation speed of the disks. Among other things, there is no mention of how to control the pressure depending on the rotation speed of the disks.

[0017] US 4,374,074 is a method for producing coarse fibers and particles (about 400 microns - as can be seen in the diagram of the achievable size of spherical particles) typical of old products produced by foundries such as blast furnace slag, steel shot, molten flux, etc. A disk without protrusions is used, so spherical powder cannot be obtained, and there is no mention of a method for removing non-spherical particles such as sausage-like particles, satellites, splats, etc., or of removing voids or hollow particles in the particles. In particular, there is no mention of a method for controlling the pressure depending on the rotation speed of the disk. When processing hot materials, the rotation speed of the disk is quite limited.

[0018] US 2,356,599 is a method for producing metal powder by grinding the material with several blades in a rotating disk. It is not possible to obtain spherical powder, and there is no mention of a method for removing non-spherical particles such as sausage-shaped particles, satellites, splats, etc., or of removing voids or hollow particles in the particles. In particular, there is no mention of a method for controlling the pressure depending on the rotation speed of the disk. The method uses a cooling liquid that is in direct contact with the ground material.

[0019] US 4,731,517 is a method for producing fine spherical powder. The disks used in this method have no protrusions. There is no mention of a method for removing non-spherical particles such as sausage-shaped particles, satellites, splats, etc., or of removing voids or hollow particles in particles. Also, some photographs of the produced powder are shown.

[0020] US 2,305,172. is a method for producing a fairly coarse metal powder (about 300 microns) by grinding the material with several blades in a rotating disk. It is not possible to obtain a spherical powder, and there is no mention of a method for removing non-spherical particles such as sausages, satellites, splats, etc., or of removing voids or hollow particles in the particles. In particular, there is no mention of a method for controlling the pressure depending on the rotation speed of the disk. In this method, a refrigerating liquid is used to cool the disk.

[0021] PCT / EP2015 / 051632 discloses a method for producing fine powders of high melting point alloys at production rates by centrifugal atomization. However, PCT / EP2015 / 051632 does not mention how to obtain very fine powders with a very low fraction of non-spherical particles or even the absence of non-spherical particles. It also does not mention how to produce very fine powders of alloys containing elements that are highly reactive towards oxygen.

[0022] However, centrifugal atomization using a rotor is difficult to operate under industrial conditions when applied to high melting point metals. Also, premature solidification of the liquid (skull) on the rotor and problems of imbalance forces, erosion, thermal fatigue and material compatibility result in a very short life span of the rotor assembly and, as a result, high maintenance costs for the rotor assembly. This has resulted in the method being envisaged only on a laboratory scale for demonstration purposes and always relevant for the production of very small batches. To solve this problem, many methods have adopted water cooling. However, this not only affects the powder morphology but also the surface oxidation, which is unacceptable for most applications aimed at very fine powders with little or no fraction of non-spherical particles, and even less feasible for alloys with phases or elements that react strongly with oxygen. One example of this is the Rapid Condensation Rate Process (RSR), developed by Pratt & Whitney-United Technologies (US 4,078,873 A and US 4,343,750 A) to produce superalloy powders. This technology is one of the most recognized centrifugal atomization techniques using rotating bodies for high melting point alloys. () The largest RSR plants have an atomization chamber with a diameter of about 5 m and a closed-loop recirculation system, and can process batches of up to 900 kg. The production rate of Ni-base superalloys reaches 1100 kg / h. In this case, the large amount of helium used is another disadvantage, since it contributes significantly to the costs. The biggest disadvantage is the need to use water cooling for the disk, which has a significant negative effect on the powder quality of many alloy systems. Due to these disadvantages, water atomization and gas atomization are the mainstream for the production of refractory metal powders.

[0023] Surprisingly, centrifugal atomization using rotating bodies has not progressed as technologically as expected due to the high cost of the powders produced. The very limited success of this type of technology applied to high melting point materials can be attributed to the technical and economic difficulties related to the quality and properties of the produced powders. These concern morphology, surface quality, microstructure (at different levels; nano and femto), small production runs, productivity ratio (yield), costs, etc. They also probably result from the conclusions drawn from the existing models depicted in Figure 1 when it comes to the production of very fine powders.

[0024] Melt atomization has many applications and advantages in the production of metal powders. Also, the main difficulty in the development of the technology has been the lack of suitable materials and methods for handling molten metals. At the same time, some of the most attractive advantages relate to the high flexibility of alloying and the control of impurities, which makes this method the only method for producing prealloyed powders. Several atomization techniques have been developed to produce metal powders and prealloyed powders from ferrous and non-ferrous alloys. Some of these techniques have been widely developed and applied in large-scale production (more than 95% of the world's atomization capacity), including two-fluid atomization, such as gas atomization, water atomization, oil atomization, vacuum atomization, and rotating electrode atomization.

[0025] Finally, it is worth noting that centrifugal or rotary atomization is much more energy efficient than water or gas atomization and produces much narrower particle size distributions, with geometric standard deviations in the range of 1.2–1.4. This technology has a maximum particle size distribution of 1.0·10 5 It can be operated at high cooling rates of ℃ / s. In a simple model, droplet formation requires a balance of forces between the acceleration force due to rotation and the surface tension of the liquid. Therefore, the average particle diameter of the centrifugal atomized particles (D 50 ) has been established to be governed and controlled by, in order of importance, angular velocity, diameter of the rotor, metal surface tension to density ratio, molten metal feed rate, and viscosity.

[0026] Despite the above advantages, centrifugal atomization, especially centrifugal disk atomization, has not been used for industrial-scale powder production due to several technical limitations. Some researchers argue that the full realization of centrifugal atomization for industrial applications is also hindered by the lack of a deep scientific understanding of the process and a reliable design. [Modelling Simul. Mater. Sci. Eng. Vol. 12, pp. 959-971, 2004, Powder Metall., Vol. 47, pp. 168-172, 2004; Proc. of Int. Conf. on Spray Deposition and Melt Forming, Bremen Universitaet, pp. 1-6, 2006] Changes in atomization technique not only result in obvious changes in the morphology, surface quality, particle size distribution, and composition of the produced powders, but also promote significant differences in the powder microstructural properties. It is well known that the structure of atomized powders is controlled by the relationship between the solidification rate, the thermal gradient, and the cooling rate, and is also influenced by the process operating conditions and the physical properties of the atomized metal. The formation of the resulting microstructure (planar, cellular, dendritic or dendrite-like microstructures) strongly depends on the combination of these and other variables that are not well understood.

[0027] PCT / EP2015 / 051632 describes some of the conditions necessary to obtain fine and very fine powders. It also describes the combination of properties necessary to obtain powders with a very small or no fraction of non-spherical particles, which is very important for very fine powder applications (especially in cases like 3D printing). On the other hand, it does not provide any insight into obtaining atomized powders that are difficult due to their low melting point, lightness or extreme reactivity. It also does not mention the solutions presented here regarding the rotating body system and the interaction of the liquid with the atmosphere.

[0028] However, contrary to what has been seen and described above, the inventor has found that by taking certain precautions, the centrifugal atomization technique using rotating bodies is suitable for the mass production of fine and very fine powders. This method also allows the production of large quantities of powders of materials with very low melting points or high reactivity, and allows the powdering of steels in the most cost-effective and environmentally friendly manner, saving a large amount of energy. What is even more surprising is that it is technically possible to exceed the theoretical limits of the minimum powder size, and what is even more remarkable is that the fraction of non-spherical particles in the powder is extremely low or non-existent. [Brief description of the drawings]

[0029] [Figure 1] Effect of rotation angular velocity on particle size in centrifugal atomization of different pure metals. Example of the effect of molten metal properties (surface tension, density, etc.) on particle size under the same processing conditions. [Diagram 2] 1. A ceramic disk with vane-like protrusions. 2. A support cage. 3. The direction and point of insertion of the metal liquid to be sprayed. 4. The contact point between the gauge and the disk that applies a horizontal compressive load to the disk. 5. The contact point between the gauge and the disk that applies a vertical compressive load to the disk. [Diagram 3] Scanning electron micrographs (SEM) of atomized powders produced by the atomization process described herein: (a) aluminum-based alloy, (b) tin-based alloy, (c) iron-based alloy, (d) tool steel surface topography details (dendritic microstructure). [Figure 4] Cross-sections of several rotating atomizers: (a) a concave disk with different parts made of different materials, (b) a one-piece disk and shaft with coating, (c) a ceramic atomizer with vanes and different parts (support cage, disk, shaft) made of different materials. [Diagram 5] Scanning electron micrograph of the atomized iron-based alloy powder shown in Example 2. The figure shows the appearance of the atomized particles, with the presence of non-spherical particles evident. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0030] In one embodiment, the inventors have found that it is possible to obtain extremely fine spherical powders or particulate material of metal-based alloys by centrifugal atomization in an atomization chamber comprising an atomizing rotor (also referred to in some embodiments as spinning, spinning disk, spinning disk atomization, atomizing disk, rotor, rotating disk or disk).

[0031] In one embodiment, a method for producing a metal-based alloy powder or particulate material by centrifugal atomization in a closed chamber comprises the steps of providing a mixture containing at least one metal, melting the mixture, and atomizing the molten metal by centrifugal or rotary atomization.

[0032] In one embodiment, the atmosphere within the enclosed spray chamber is pressurized or cooled.

[0033] The inventors have found that in order to produce ultrafine spherical powders with very little or no non-spherical powder and very little or no spherical powder particles containing voids or hollow spheres, it is necessary to employ a suitable combination of production parameters, with very surprising values. The inventors have also found, surprisingly, that atomization chambers using gas pressurized above atmospheric pressure can be used to produce highly spherical, non-deformed particles, provided that certain precautions are taken with regard to the flow of metal to the disk, the superheat temperature of the metal, the nature of the disk, the shape of the disk, the material being atomized, the atmosphere in the chamber, and the speed of the disk.

[0034] In some embodiments, a suitable combination of the rotational speed of the disk, the effective diameter of the disk, and the pressure of the atmosphere in the atomization chamber is sufficient. In one embodiment, the inventors have found PA1 to be of consideration. PA1=r * N 2* d 2 Where: r is the density of the spray liquid at the melting point at 1 bar absolute pressure in kilograms per cubic meter [kg / m 3], N is the rotational speed of the disk in radians per second [rad / s], and d is the diameter of the disk in meters. The unit of the parameter PA1 is kilograms per meter squared [kg / (m s 2 ) In one embodiment, the atomizing liquid refers to the molten composition atomized in step c). Taking the constants K1 and K2, which depend on the nature of the material being processed and the atmosphere in the chamber, and P, the absolute pressure in the atomizing chamber in Pascals [Pa], the inventors have defined two critical parameters, namely PA2 and PA3, which are defined below: PA2=K1 * PA1+K2 * P PA3=PA1 / P.

[0035] In some applications, generalized values ​​(same for all types of alloys atomized) can be applied. In one embodiment, for aluminum-based alloys, K1=0.01, K2=20. In one embodiment, for magnesium-based alloys, K1=0.015, K2=22. In one embodiment, for iron-based alloys, K1=0.0033, K2=20. In one embodiment, for nickel-, copper-, or cobalt-based alloys, K1=0.0033, K2=21. In one embodiment, for any alloy, K1=0.0033, K2=22. In one embodiment, for titanium-based alloys, K1=0.006, K2=20. K1 and K2 have the appropriate units so that PA2 is dimensionless (1 / Pa). It has been found that precise values ​​are necessary for PA2, but small values ​​are sufficient for PA3. In some embodiments, PA2 is greater than 4.5 million. In some other embodiments, PA2 is greater than 5 million. In some other embodiments, PA2 is greater than 6 million. In some other embodiments, PA2 is greater than 7 million. In some other embodiments, PA2 is less than 70 million. In some other embodiments, PA2 is less than 40 million. In some other embodiments, PA2 is less than 30 million. In some other embodiments, PA2 is less than 20 million. In some other embodiments, PA3 is less than 10 million. In some other embodiments, PA3 is less than 7000. In some other embodiments, PA3 is less than 6000. In some other embodiments, PA3 is less than 5000. In another embodiment, PA3 is less than 1000. All the above embodiments may be combined with each other, provided they are not mutually exclusive. For example, PA2 is greater than 4.5 million and less than 70 million, or PA2 is greater than 4.5 million and less than 40 million, or PA2 is greater than 4.5 million and less than 30 million, etc. The inventors have found that in some applications, when an appropriate combination of manufacturing parameters is employed, a surprisingly narrow particle size distribution of fine and spherical powders with excellent morphological quality can be obtained.Moreover, the powder has a higher metallic tone that is preferred by end users implementing some applications. Also, powders can be produced that are substantially completely free of particles with thick oxide crusts and have exceptionally low or no internal porosity. The inventors have also found that with the proper combination of manufacturing parameters, fine powders can be produced at surprisingly lower costs than observed with the methods disclosed in the Background section of this specification. In some applications, the proper combination of manufacturing parameters can also result in a fine or spherical powder size distribution with excellent flow properties. In some applications, when the proper combination of manufacturing parameters is employed, the level of microsegregation in the atomized powder is surprisingly lower than expected. In addition to the proper values ​​of PA2 and PA3, the inventors have found that in some embodiments, a pressurized chamber is preferred. In some applications, pressures above atmospheric pressure are of particular interest to contribute to the desired morphology. The inventors have found that in some embodiments, supercooling must be avoided to maintain the morphological quality of the powder or particulate material produced. This means that special measures must be taken, for example by selecting appropriate values ​​for PA2 and PA3, so that pressurization in the chamber does not lead to subcooling. In an embodiment, an overpressure of at least 0.12 bar relative to atmospheric pressure is preferred. In an embodiment, the absolute pressure in the spray chamber is greater than 1.2 bar. In another embodiment, the absolute pressure in the spray chamber is greater than 1.6 bar. In another embodiment, the absolute pressure in the spray chamber is greater than 2.4 bar. In another embodiment, the absolute pressure in the spray chamber is greater than 2.6 bar. In another embodiment, the absolute pressure in the spray chamber is greater than 2.8 bar. In another embodiment, the absolute pressure in the spray chamber is greater than 3.1 bar. In another embodiment, the absolute pressure in the spray chamber is greater than 4.3 bar. In another embodiment, the absolute pressure in the spray chamber is greater than 5.7 bar. In some applications, even higher levels of absolute pressure in the spray chamber are preferred. In one embodiment, the absolute pressure in the spray chamber is greater than 6.1 bar. In another embodiment, the absolute pressure in the spray chamber is greater than 7.3 bar. In another embodiment, the absolute pressure in the spray chamber is greater than 8.2 bar.In another embodiment, the absolute pressure in the atomizing chamber is greater than 9.1 bar. In another embodiment, the absolute pressure in the atomizing chamber is greater than 9.8 bar. In some specific applications, depending on the alloy and the form of the powder or particulate being atomized, atomization may occur at atmospheric pressure or below atmospheric pressure. In one embodiment, the absolute pressure in the atomizing chamber is greater than 0.001 bar. In another embodiment, the absolute pressure in the atomizing chamber is greater than 0.1 bar. In another embodiment, the absolute pressure in the atomizing chamber is greater than 0.26 bar. In another embodiment, the absolute pressure in the atomizing chamber is greater than 0.52 bar. In another embodiment, the absolute pressure in the atomizing chamber is greater than 0.92 bar. In other applications, the inventors have found that the values ​​of PA2 and PA3 disclosed above can be reached if the pressure in the atomizing chamber is maintained below a certain value. In one embodiment, the absolute pressure in the atomizing chamber is less than 999.4 bar. In another embodiment, the absolute pressure in the spray chamber is less than 99.2 bar. In another embodiment, the absolute pressure in the spray chamber is less than 29.6 bar. In another embodiment, the absolute pressure in the spray chamber is less than 19.2 bar. In another embodiment, the absolute pressure in the spray chamber is less than 14.3 bar. In another embodiment, the absolute pressure in the spray chamber is less than 9.4 bar. In some applications, even lower levels of absolute pressure in the spray chamber are preferred. In one embodiment, the absolute pressure in the spray chamber is less than 6.1 bar. In another embodiment, the absolute pressure in the spray chamber is less than 4.2 bar. In another embodiment, the absolute pressure in the spray chamber is less than 2.9 bar. In another embodiment, the absolute pressure in the spray chamber is less than 1.4 bar. In another embodiment, the absolute pressure in the spray chamber is less than 1.2 bar. All of the above-mentioned embodiments may be combined with each other, provided they are not mutually exclusive. There are other combinations, for example, absolute pressure in the atomization chamber above 1.2 bar and below 999.4 bar, or absolute pressure in the atomization chamber above 2.6 bar and below 29.6 bar, or absolute pressure in the atomization chamber above 2.8 bar and below 19.2 bar, etc. In some specific applications, the present inventors have found that in some embodiments, it is preferable that the composition to be atomized (the composition provided in step a) is melted and superheated. In one embodiment, the composition to be atomized is superheated at a temperature 10° C. above the melting point.In some other embodiments, the composition to be atomized is superheated to a temperature 52°C above the melting point. In some embodiments, the composition to be atomized is superheated to a temperature 106°C above the melting point. In some embodiments, the composition to be atomized is superheated to a temperature 159°C above the melting point. In some embodiments, the composition to be atomized is superheated to a temperature 212°C above the melting point. In some embodiments, the composition to be atomized is superheated to a temperature 256°C above the melting point. In some embodiments, the composition to be atomized is superheated to a temperature 306°C above the melting point. In other applications, it is preferred that the composition to be atomized is superheated to a small degree. In some embodiments, the superheat is less than 396°C+Tm, where Tm is the melting point of the composition to be atomized in degrees Celsius (°C). In another embodiment, the temperature of superheating is less than 294°C+Tm, where Tm is the melting point of the composition to be atomized in degrees Celsius (°C). In another embodiment, the temperature of superheating is less than 144°C+Tm, where Tm is the melting point of the composition to be atomized in degrees Celsius (°C). In another embodiment, the temperature of superheating is less than 96°C+Tm, where Tm is the melting point of the composition to be atomized in degrees Celsius (°C). In another embodiment, the temperature of superheating is less than 47°C+Tm, where Tm is the melting point of the composition to be atomized in degrees Celsius (°C). Here, melting point refers to the absolute temperature at which the first liquid is formed in equilibrium. In one embodiment, the composition to be atomized is the composition obtained in step a).

[0036] Surface tension is an intrinsic property, and therefore it can only be measured inaccurately by different measurement methods giving different results. The technique used to measure an intrinsic property is not important, as long as the measurement is performed in the correct way. In one embodiment, for wetting angle and surface tension, for convenience, both are measured with the same device using the sessile drop method. In one embodiment, the measurement of contact angle to determine wettability is as described in ISIJ Int. (by CJ Xuan, H. Shibata, Z. Zhao, PG Joensson and K. Nakajima) from p. 1642 onwards. In another alternative embodiment, the surface tension can be calculated using the contour fitting method described in Surface Tension, Part II: The measurement of Surface Tension; in Surface and Colloid Science, vol 1, edited by E. Matijevic, Clarkson College of Technology, NY, (1969) (by JF Paddy) from p. 108 onwards. In another alternative embodiment, the Adams-Bashforce method can be used. The type of alloy and the type of substrate being measured must match those used in the application, and the substrate must match the disk material, molten metal, and the alloy being atomized. In one embodiment, the roughness (Ra) of the substrate being measured matches the average roughness of the disk surface in contact with the molten metal when the disk is new. In one embodiment, the roughness of the substrate is controlled to Ra=5 microns. In one embodiment, the temperature is adjusted to be 20K above the liquidus temperature. In another alternative embodiment, the temperature of the test is adjusted to the liquidus temperature. The liquidus temperature is the absolute temperature at which the material is completely liquid. In one embodiment, the cooling rate after the maintenance period is adjusted to be 20K / min. In one embodiment, the oxygen partial pressure at the entrance is 10 -20 In one embodiment, the average oxygen partial pressure in the measurement chamber during the measurement is adjusted to 10 -21Atmospheres. In one embodiment, the measurements are performed at less than 99.999 argon atmosphere. In one embodiment, the measurements are performed at 10 -8 In one embodiment, the measurements are performed at 99.99 H 2 The measurements are carried out in an atmosphere of 100° C. In most embodiments, the value to be adopted is the stable value. In one embodiment, the stable value (applies to both contact angle and surface tension) is the value 500 seconds after the moment of complete melting. In some embodiments, the stabilized value is the value obtained in the first measurement, which undergoes a variation less than a threshold value (1° for contact angle and 50 mN / m for surface tension) within 100 seconds after recording. In some embodiments, the value to be used is the initial value within 2 seconds of complete melting.

[0037] In some applications, generalized (meaning applicable to all alloys that can be atomized) rules for contact angle and surface tension can be applied. Furthermore, in very many cases (with some exceptions), the surface tension and contact angle rules do not work in isolation and must be applied in conjunction with other rules herein to solve the problem. In some embodiments, the surface tension and contact angle rules must be applied in conjunction with parameters taking into account the chamber pressure and the rotational speed of the disk. In some embodiments, the surface tension and contact angle rules must be applied in conjunction with restrictions on the chemical composition of the alloy being melted.

[0038] In one embodiment, the inventors have found that the method disclosed herein is particularly suitable for producing aluminum-based alloys in powder or particulate form. In one embodiment, the composition of at least one metal obtained in step a) refers to a composition of an aluminum-based alloy. In the case of aluminum and aluminum-based alloys, it has been found that many physical or mechanical properties such as thermal expansion coefficient, thermal conductivity, fracture toughness, density, mechanical strength, etc., appear to determine the possibility of being a good candidate for a disk material. Some of the nominal properties tend to deteriorate, and in many cases are very strong in the presence of the processed molten alloy, which is of utmost importance for the durability of the disk, which determines whether the manufacturing is economically viable. It should also be remembered that the mechanical loads on the disk are very exceptional and incomparable to others in existing melting processes. Surprisingly, it has been found that, noting some rules that apply to the properties that are subject to change in the presence of molten metal, these appear to work under certain processing conditions. It has been found that in some applications it is sufficient to ensure that the contact angle is within a certain range of values ​​defined by a maximum and a minimum value. In one embodiment, the maximum value of the contact angle is 168°. In another embodiment, the maximum contact angle is 158°. In another embodiment, the maximum contact angle is 148°. In another embodiment, the maximum contact angle is 138°. In another embodiment, the minimum contact angle is 76°. In another embodiment, the minimum contact angle is 96°. In another embodiment, the minimum contact angle is 126°. In another embodiment, the minimum contact angle is 106°. In another embodiment, the minimum contact angle is 136°. All of the above embodiments may be combined with each other, provided they are not mutually exclusive. For example, a contact angle of 76° or more and 168° or less is possible. The contact angle (also known as Young's angle) is an intrinsic property of solid-liquid-gas systems. This value quantifies the suitability of a non-reactive liquid to spread over a flat, non-deforming, perfectly smooth, and chemically homogeneous solid surface. The contact angle is one of the most common parameters for measuring the wettability of a surface.Wettability generally refers to how a liquid spreads when deposited on a solid substrate, or the ability of the liquid to form an interface with the solid state. A completely wettable substrate will have a contact angle of zero. A non-wetting liquid will therefore have a contact angle with a solid surface between 90° and 180°. It has been found that in some applications it is desirable not only for the contact angle to be within a certain range of values ​​at least at the melting point, but also for it to have a specific behavior with increasing temperature above the melting point, i.e. the disk material and its preparation should be selected accordingly. Let Tm be the melting point, where T is the temperature above the melting point, but not more than 500°C below the melting point. In some embodiments, the contact angle measured in degrees is preferably between Cs and Ci, where Cs=185°-0.2. * (T-Tm) and Ci=120°-0.2 *(T-Tm), where T and Tm are expressed in degrees Celsius (°C). In one embodiment, the contact angle decreases by more than 2.5% for every 100°C increase in temperature above the melting point with a maximum superheat of 500°C. In another embodiment, the contact angle decreases by more than 7.5% for every 200°C increase in temperature above the melting point with a maximum superheat of 500°C. In some applications, it has been found that the disk material should be selected depending on the material to be atomized, taking into account a very specific desired behavior of the surface tension between the two materials. In some applications, it has been found that it is sufficient to ensure that the surface tension value between the molten material and the disk material is within a certain range of values ​​defined by a maximum and a minimum value. In one embodiment, it is desirable for the maximum value of the surface tension to be 1750 mN / m. In another embodiment, it is desirable for the maximum value of the surface tension to be 1550 mN / m. In another embodiment, it is desirable for the maximum value of the surface tension to be 1450 mN / m. In another embodiment, the maximum value of the surface tension is preferably 1250 mN / m. In another embodiment, the minimum value of the surface tension is preferably 680 mN / m. In another embodiment, the minimum value of the surface tension is preferably 780 mN / m. In another embodiment, the minimum value of the surface tension is preferably 820 mN / m. In another embodiment, the minimum value of the surface tension is preferably 960 mN / m. In another embodiment, the minimum value of the surface tension is preferably 1080 mN / m. All the above embodiments may be combined with each other, provided they are not mutually exclusive. For example, a combination of a surface tension of 680 mN / m or more and 1750 mN / m or less. It has been found that in some applications, the surface tension should be selected to ensure a decrease in the surface tension between the working disk surface and the material being atomized that decreases with increasing temperature in a specific manner. If Tm is the melting point, then T is the temperature above the melting point, where T is 500° C. below the melting point. In one embodiment, the surface tension is preferably between ST and STi, where STs=1450-0.8 * (T-Tm), STi=820-0.7 *(T-Tm), where in each case the surface tension is measured in mN / m, and T and Tm are in degrees Celsius (°C). In one embodiment, the surface tension decreases by 1.3% or more for every 100°C increase in temperature above the melting point with a maximum superheat of 500°C. In another embodiment, the surface tension decreases by 6.1% or more for every 200°C increase in temperature above the melting point with a maximum superheat of 500°C. It has been found that the morphological quality can be influenced by the composition of the alloy being melted. In this regard, some elements have similar effects to each other in some applications and configurations of the invention and are classified into groups I and II. In one embodiment, the group I elements must be 0.3 wt% or more. In another embodiment, the group I elements must be 2.2 wt% or more. In another embodiment, the group I elements must be 3.1 wt% or more. In another embodiment, the Group I elements must be 4.2 wt% or more. In another embodiment, the Group I elements must be 4.6 wt% or more. In another embodiment, the Group I elements must be 5.2 wt% or more. In another embodiment, the Group I elements must be 7.3 wt% or more. In one embodiment, the Group I elements can be 9.8 wt% or less. In another embodiment, the Group I elements can be 6.8 wt% or less. In another embodiment, the Group I elements can be 3.8 wt% or less. In another embodiment, the Group I elements can be 2.8 wt% or less. In another embodiment, the Group I elements can be 1.8 wt% or less. In another embodiment, the Group I elements can be 0.9 wt% or less. In one embodiment, the Group II elements must be 0.002 wt% or more. In another embodiment, the Group II elements should be 0.02 wt% or more. In another embodiment, the Group II elements should be 0.2 wt% or more. In another embodiment, the Group II elements should be 1.1 wt% or more. In another embodiment, the Group II elements should be 1.8 wt% or more. In another embodiment, the Group II elements should be 2.2 wt% or more. In one embodiment, the Group II elements can be 5.9 wt% or less. In another embodiment, the Group II elements can be 3.9 wt% or less. In another embodiment, the Group II elements can be 2.4 wt% or less.In another embodiment, the Group II elements may be 1.4 wt% or less. In another embodiment, the Group II elements may be 0.9 wt% or less. In another embodiment, the Group II elements may be 0.09 wt% or less. In an embodiment, at least one element of Group I and at least one element of Group II must be present. In an embodiment, at least one element of Group I and at least two elements of Group II must be present. At least one element of Group I and at least three elements of Group II must be present. In an embodiment, at least two elements of Group I and at least one element of Group II must be present. In an embodiment, at least two elements of Group I and at least two elements of Group II must be present. In an embodiment, at least two elements of Group I and at least three elements of Group II must be present. In an embodiment, magnesium is a Group I element. In an embodiment, silicon is a Group I element. In one embodiment, zinc is a Group I element. In one embodiment, scandium is a Group II element. In one embodiment, copper is a Group II element. In one embodiment, manganese is a Group II element. In one embodiment, iron is a Group II element. In one embodiment, scandium is a Group II element. In some applications, some elements must be kept below certain levels for some configurations of the invention. These elements promote intra-sphere voids and also the appearance of non-spherical particles. In one embodiment, K-type elements must be kept below 94 ppm by weight. In another embodiment, K-type elements must be kept below 48 ppm by weight. In another embodiment, K-type elements must be kept below 24 ppm by weight. In another embodiment, K-type elements must be kept below 9 ppm by weight. In another embodiment, K-type elements must be kept below 0.8 ppm by weight. In some embodiments, the absence of K-type elements is desired. In some embodiments, potassium is a K-type element. In some embodiments, phosphate is a K-type element. In some embodiments, chromium is a K-type element. In some embodiments, S-type elements should be limited to less than 0.8 ppm by weight.In another embodiment, S-type elements should be limited to less than 0.08 ppm by weight. In another embodiment, S-type elements should be limited to less than 0.04 ppm by weight. In another embodiment, S-type elements should be limited to less than 0.008 ppm by weight. In one embodiment, it is preferred that no S-type elements are present. In one embodiment, antimony is an S-type element. In one embodiment, lithium is an S-type element. In one embodiment, N-type elements should be limited to less than 590 ppm by weight. In another embodiment, N-type elements should be limited to less than 190 ppm by weight. In another embodiment, N-type elements should be limited to less than 90 ppm by weight. In another embodiment, N-type elements should be limited to less than 20 ppm by weight. In another embodiment, N-type elements should be limited to less than 9 ppm by weight. In one embodiment, it is preferred that no N-type elements are present. In one embodiment, sodium is an N-type element. In one embodiment, gallium is an N-type element. In one embodiment, calcium is an N-type element. In one embodiment, %Sr may be present in the aluminum-based alloy, but if so, it must be kept below 1.9 wt% by weight. As will be described below, in some other inventive embodiments, some of these elements can be controlled to produce powders or particulates that are difficult to manufacture, even when present in very high amounts, such as in the case of gallium and lithium. In the initial ceramic material screening, several titanates were considered as good candidates for the disk material, given their low thermal expansion and resistance to thermal shock. Unfortunately, in this invention, due to the very high mechanical loads, their thermal shock resistance was not sufficient to be evaluated as a good alloy casting material for this invention. The mechanical strength requirement cannot be evaluated on short-term mechanical properties, as the molten alloy tends to deteriorate rather quickly in the atomized state. Titanium is an example. Barium titanate has fallen into disuse as a disk material due to the publication of "Effect of grain boundary cracking on the corrosion behavior of aluminum titanate ceramics in aluminum alloy molten metal" (Makoto Tanaka, Kazumi Kashiwagi, Naoki Kawashima, Satoshi Kitaoka, Osamu Sakurada and Yutaka Ohya-in Corrosion Science volume 54_January 2012, pages 90-96). In fact, many ceramics that are often used as casting ceramics with good mechanical properties unfortunately suffer from liquid metal embrittlement in molten aluminum. Surprisingly, the inventors found that barium titanate exhibited higher durability than expected and could be effectively used as a disk material when they first tried using powder ceramics under the specific conditions of the present invention. Subsequent investigations showed that barium could also be replaced, at least in part, by strontium with the same effect. Subsequent investigations showed that barium could also be replaced, at least in part, by strontium with the same effect. In one embodiment, the disk material described in this paragraph is applied as a thick coating on a metal material. In some embodiments, the atomizing rotor may be coated or uncoated, or may be partially coated or multi-coated. In some applications, a multi-layer coating is preferred. In one embodiment, the coating comprises at least two layers. In another embodiment, it comprises at least three layers. In some applications, the atomizing disk may be preferably coated with a material similar to the alloy to be atomized, or a stable component thereof, or a similar material, to improve wettability. This should be considered especially in some applications where greater wettability is preferred. The inventors have found that, regardless of the material of the substrate, the coating layer may be applied using different materials in some applications and may be effectively used as a coating material. In one embodiment, the atomizing disk is at least partially coated with two or more coating layers of different compositions.In some applications, a multi-layer coating consisting of a ceramic coating layer and a metallic coating layer is preferred, while in other applications, a multi-layer coating consisting of a metallic coating layer and a ceramic coating layer is preferred. In one alternative embodiment, the first coating layer applied on the atomizing disk is a metallic coating layer. Several coating techniques are suitable, such as high velocity oxygen flame spraying (HVOF), chemical vapor deposition (CVD), physical vapor deposition (PVD), plasma spraying, thermal spraying or projection, low temperature gas spraying, cladding, fluidized bed, chemical or electrochemical techniques, and many others. In one embodiment, the coating thickness is 2.1 microns or more. In another embodiment, the coating thickness is 8.1 microns or more. In another embodiment, the coating thickness is 22.1 microns or more. In another embodiment, the coating thickness is 72.1 microns or more. In another embodiment, the coating thickness is 103 microns or more. In another embodiment, the coating thickness is 160 microns or more. In another embodiment, the coating thickness is 280 microns or more. In another embodiment, the coating thickness is 370 microns or more. In another embodiment, the coating thickness is 560 microns or more. In another embodiment, the coating thickness is greater than 1.06 mm. In some applications, it is desirable to have a coating thickness less than a certain value. In one embodiment, the coating thickness is 1.9 mm. In another embodiment, the coating thickness is less than 990 microns. In another embodiment, the coating thickness is less than 490 microns. In another embodiment, the coating thickness is less than 390 microns. In another embodiment, the coating thickness is less than 240 microns. In another embodiment, the coating thickness is less than 106 microns. In another embodiment, the coating thickness is less than 84 microns. In another embodiment, the coating thickness is less than 62 microns. In another embodiment, the coating thickness is less than 48 microns. All of the above embodiments may be combined with each other, provided they are not mutually exclusive. There are other combinations, such as a coating thickness of 2.1 microns or more and 990 or less.In some embodiments, when the coating comprises two or more layers, the thickness values ​​disclosed above refer to the thickness of each coating layer. In some embodiments, the disk material to which the coating is applied comprises an intermetallic compound. In some embodiments, the above rules for aluminum-based alloys can be extended to magnesium-based alloys. In some embodiments, the above rules for aluminum-based alloys can be extended to lithium-based alloys. In some embodiments, the above rules for aluminum-based alloys can be extended to copper-based alloys. In some embodiments, the above rules for aluminum-based alloys can be extended to germanium-based alloys. In some embodiments, the above rules for aluminum-based alloys can be extended to lithium-based alloys. In some embodiments, the above rules for aluminum-based alloys can be extended to silver-based alloys. In some embodiments, the above rules for aluminum-based alloys can be extended to gold-based alloys. Another surprise is that TiB, which overturns short-term identified advantages and is also related to reduced durability due to embrittlement cracking in mechanically highly loaded systems such as those described herein. 2 (titanium diboride), another ceramic that was ruled out by "Mechanical Properties of High Density Sintered Compacts of High Purity Titanium Diboride in an Aluminum Melting Environment" (HR Baumgartner; July 1984), which refers to avoiding the use of titanium diboride. Quite surprisingly, in some embodiments of the present invention, this has performed very well with very long durability. In one embodiment, the disk blank is comprised of titanium diboride. In one embodiment, the disk blank is comprised of titanium diboride with deviations from stoichiometry. In one embodiment, titanium diboride is incorporated into the disk blank as a coating.

[0039] In one embodiment, the inventors have found that the method disclosed herein is particularly suitable for producing iron or iron-based alloys in powder or particulate form. In one embodiment, the composition of at least one metal obtained in step a) refers to a composition of an iron-based alloy. In the case of iron or iron-based alloys, it has been found that many physical or mechanical properties such as thermal expansion coefficient, thermal conductivity, fracture toughness, density, mechanical strength, etc., appear to determine the possibility of being a good candidate for a disk material. Some of the nominal properties tend to deteriorate, and in many cases are very strong in the presence of the processed molten alloy, which is of utmost importance for the durability of the disk, which determines whether the manufacturing is economically viable. It should also be remembered that the mechanical loads on the disk are very exceptional and incomparable to others in existing melting processes. Surprisingly, it has been found that, noting some rules that apply to the properties that are subject to change in the presence of molten metal, these appear to work under certain processing conditions. It has been found that in some applications it is sufficient to ensure that the contact angle is within a certain range of values ​​defined by a maximum and a minimum. In one embodiment, the maximum value of the contact angle is 172°. In another embodiment, the maximum contact angle is 156°. In another embodiment, the maximum contact angle is 148°. In another embodiment, the maximum contact angle is 139°. In another embodiment, the minimum contact angle is 76°. In another embodiment, the minimum contact angle is 98°. In another embodiment, the minimum contact angle is 104°. In another embodiment, the minimum contact angle is 116°. In another embodiment, the minimum contact angle is 132°. All the above embodiments may be combined with each other, provided they are not mutually exclusive. For example, a contact angle of 76° or more and 172° or less. It has been found that in some applications, it is desirable not only for the contact angle to be within a certain range of values ​​at least at the melting point, but also for it to have a specific behavior with increasing temperature above the melting point, i.e. the disk material and its preparation should be selected accordingly. If Tm is the melting point, then T is the temperature above the melting point, provided that T is 500°C below the melting point.In one embodiment, the contact angle measured in degrees is preferably between Cs and Ci, where Cs=185°-0.2. * (T-Tm) and Ci=120-0.2 *(T-Tm), where T and Tm are expressed in degrees Celsius (°C). In one embodiment, the contact angle decreases by more than 1.5% for every 100°C increase in temperature above the melting point with a maximum superheat of 500°C. In another embodiment, the contact angle decreases by more than 5.5% for every 200°C increase in temperature above the melting point with a maximum superheat of 500°C. In some applications, it has been found that the disk material should be selected depending on the material to be atomized, taking into account a very specific desired behavior of the surface tension between the two materials. In some applications, it has been found that it is sufficient to ensure that the surface tension value between the molten material and the disk material is within a certain range of values ​​defined by a maximum and a minimum value. In one embodiment, it is desirable for the maximum value of the surface tension to be 2190 mN / m. In another embodiment, it is desirable for the maximum value of the surface tension to be 1990 mN / m. In another embodiment, it is desirable for the maximum value of the surface tension to be 1690 mN / m. In another embodiment, the maximum value of the surface tension is preferably 1590 mN / m. In another embodiment, the minimum value of the surface tension is preferably 810 mN / m. In another embodiment, the minimum value of the surface tension is preferably 910 mN / m. In another embodiment, the minimum value of the surface tension is preferably 1010 mN / m. In another embodiment, the minimum value of the surface tension is preferably 1110 mN / m. In another embodiment, the minimum value of the surface tension is preferably 1510 mN / m. All the above embodiments may be combined with each other, provided they are not mutually exclusive. For example, a combination of a surface tension of 810 mN / m or more and 2190 mN / m or less. It has been found that in some applications, the temperature should be selected to ensure a decrease in the surface tension between the working disk surface and the material being atomized that decreases with increasing temperature in a particular manner. Let Tm be the melting point, and T be the temperature above the melting point. where T is the melting point below 500° C. In one embodiment, the surface tension is preferably between ST and STi, where STs=1700-0.8 * (T-Tm), STi=1100-0.9 *(T-Tm), where in each case the surface tension is measured in mN / m, and T and Tm are in degrees Celsius (°C). In one embodiment, the surface tension decreases by at least 1.1% for every 100°C increase in temperature above the melting point with a maximum superheat of 500°C. In another embodiment, the surface tension decreases by at least 5.1% for every 200°C increase in temperature above the melting point with a maximum superheat of 500°C. The inventors have found that some alloying elements in the liquid affect the surface tension and contact angle, and some affect the breakup of the liquid during atomization, tending to allow for finer or coarser powders. One such element is sulfur (S), which has been found to be operable in some embodiments to promote the formation of very fine powders. In one embodiment, it is desirable for the %S to be greater than 25 ppm by weight. In another embodiment, it is desirable for the %S to be greater than 55 ppm by weight. In another embodiment, it is desirable for the %S to be greater than 115 ppm by weight. In another embodiment, it is desirable for the %S to be greater than 550 ppm by weight. In another embodiment, it is desirable for the %S to be greater than 750 ppm by weight. In another embodiment, it is desirable for the %S to be greater than 0.12 wt%. In one embodiment, it has been found that in such cases special care needs to be taken to ensure a sufficiently low level of %S, since %S will ruin everything and give powders with intra-sphere voids inside. In one embodiment, it is desirable for the %S to be less than 400 ppm by weight. In another embodiment, it is desirable for the %S to be less than 90 ppm by weight. In another embodiment, it is desirable for the %S to be less than 39 ppm by weight. In another embodiment, it is desirable for the %S to be less than 19 ppm by weight. In another embodiment, it is desirable for the %S to be less than 9 ppm by weight. In another embodiment, it is desirable for the %S to be less than 4 ppm by weight. In certain embodiments, the absence of %S is desirable. In some embodiments, the same effect as %S, but to a lesser extent, has been observed with %P. In some embodiments, %P is desirable to be greater than 55 ppm by weight. In other embodiments, %P is desirable to be greater than 115 ppm by weight. In other embodiments, %P is desirable to be greater than 550 ppm by weight.In another embodiment, it is desirable for the %P to be greater than 750 ppm by weight. In another embodiment, it is desirable for the %P to be greater than 0.12 wt%. In one embodiment, it has been found that %P will ruin everything and give powders with intra-sphere voids inside, so in these cases special care needs to be taken to ensure a sufficiently low level of %P. In one embodiment, it is desirable for the %P to be less than 400 ppm by weight. In another embodiment, it is desirable for the %P to be less than 90 ppm by weight. In another embodiment, it is desirable for the %P to be less than 39 ppm by weight. In another embodiment, it is desirable for the %P to be less than 29 ppm by weight. In another embodiment, it is desirable for the %P to be less than 19 ppm by weight. In another embodiment, it is desirable for the %P to be less than 9 ppm by weight. In some embodiments, the absence of %P is desirable. The inventor has found that in some cases %B (boron) can also achieve this effect. In one embodiment it is desirable for %B to be greater than 6 ppm by weight. In another embodiment it is desirable for %B to be greater than 11 ppm by weight. In another embodiment it is desirable for %B to be greater than 25 ppm by weight. In another embodiment it is desirable for %B to be greater than 45 ppm by weight. In another embodiment it is desirable for %B to be greater than 0.12 wt%. In one embodiment it has been found that %B ruins everything and gives powders with intra-sphere voids inside, so in such cases special care needs to be taken to ensure a sufficiently low level of %B. In one embodiment it is desirable for %B to be less than 400 ppm by weight. In another embodiment it is desirable for %B to be less than 90 ppm by weight. In another embodiment it is desirable for %B to be less than 39 ppm by weight. In another embodiment it is desirable for %B to be less than 29 ppm by weight. In another embodiment it is desirable for %B to be less than 19 ppm by weight. In other embodiments, it is desirable for %B to be less than 9 ppm by weight. In some embodiments, the absence of %B is desirable. In some applications, %C should be kept at a moderate level, as it promotes the formation of intra-sphere voids in the powder in some compositions. In some embodiments, %C should be kept below 4.9 wt%.In another embodiment, %C should be kept below 3.4 wt%. In another embodiment, %C should be kept below 1.9 wt%. In another embodiment, %C should be kept below 0.9 wt%. In one embodiment, if the sum of %Mo+%Cr+%W+%V+%Si+%Mn is greater than 10.5 wt% then %C should be kept below 1.9 wt%. In one embodiment, if the sum of %Cr+%Ta+%Hf is greater than 10 wt% then %C should be kept below 1.9 wt%. The inventors have found that the oxygen content in the molten metal being atomized is often a very important variable to control, and therefore special attention must be paid to the method of deoxidation. In the case of steels, particularly those usable as tool steels, stainless steels in one embodiment, tool steels, it is important to closely control %Si, %Ti, or %Al. In one embodiment, %Si should not be used as a deoxidizing element, since it has been demonstrated that the particular way in which oxidation occurs with this element has a large impact on the usability of the powder, and in fact the residual amount of %Si needs to be strictly controlled. In one embodiment, %Si is preferably less than 0.29 wt%. In another embodiment, %Si is preferably less than 0.19 wt%. In another embodiment, %Si is preferably less than 0.09 wt%. In another embodiment, %Si is preferably less than 0.04 wt%. In another embodiment, %Si is preferably less than 0.009 wt%. In one embodiment, it is preferable that %Si is absent. In one embodiment, %Si is a critical alloying element, and the final application determines the amount added. In one embodiment, %Al should not be used as a deoxidizing element, since it has been demonstrated that the particular way in which oxidation occurs with this element has a large impact on the usability of the powder, and in fact the residual amount of %Al needs to be strictly controlled next to %Si. In one embodiment, %Al must be less than 0.09 wt%. In another embodiment, %Al must be less than 0.04 wt%. In another embodiment, %Al must be less than 0.009 wt%. In another embodiment, %Al must be less than 0.004 wt%.In another embodiment, %Al should be less than 0.0009 wt%. In some embodiments, the absence of %Al is desired. In some embodiments, %Al is a critical alloying element, with the final application determining the amount added. In some embodiments, Ti is a suitable element for deoxidation, and in some embodiments, during alloying by deoxidation. In order to achieve this, it is desirable to have more than trace levels of %Ti remaining. Steels with moderate or even high %C content can benefit from the deoxidization of %Ti, especially in materials with a fairly low %C content. However, the residual %Ti content must be controlled to ensure that it is not excessive. In one embodiment, %Ti must be greater than 0.0012wt%. In another embodiment, %Ti must be greater than 0.0012wt%. In another embodiment, %Ti must be greater than 0.012wt%. In another embodiment, %Ti must be greater than 0.052wt%. In another embodiment, %Ti must be greater than 0.32wt%. In one embodiment, %Ti should not be employed as a deoxidizing element, and in fact the residual amount must be strictly controlled, since it has been demonstrated that %Ti has a significant impact on the usability of the powder due to the specific way in which it reacts with %C to form brittle, large, irregular primary carbides. In one embodiment, %Ti should be less than 0.09 wt%. In another embodiment, %Ti should be less than 0.04 wt%. In another embodiment, %Ti should be less than 0.009 wt%. In another embodiment, %Ti should be less than 0.004 wt%. In another embodiment, %Ti should be less than 0.0009 wt%. In one embodiment, the absence of %Ti is desired. In one embodiment, %Ti is a critical alloying element and the final application determines the amount added. In some embodiments, the above rules for %Si, %Al and %Ti steels can be extended to iron-based alloys. In some embodiments, the above rules for %Si, %Al and %Ti steels can be extended to nickel-based alloys. In some embodiments, it is not preferable to deoxidize with any of Si, %Al, and %Ti, but more expensive deoxidizing elements such as %Sc and %Zr can be employed when the amount of oxygen in the molten liquid to be sprayed must be strictly controlled. Considering thermal shock resistance, the inventors have found that alumina (Al 2 O 3) has been found to be a suitable disk material in certain embodiments. For applications with highly superheated melts poured onto a much cooler disk, aluminum nitride (AlN) may also be considered. In some embodiments, the disk may be made of a highly stable oxide such as magnesium oxide (MgO). In some embodiments, the disk is desired to be made of an oxide in which the metal portion operates at an oxidation number III or higher. In some embodiments, the disk is desired to have a majority of oxides in which the metal portion operates at an oxidation number III or higher. In some embodiments, the disk is desired to have a majority of oxides in which the metal portion operates at an oxidation number IV or higher. In some embodiments, the disk is desired to have a majority of oxides in which the metal portion operates at an oxidation number IV or higher. The most surprising observation was made with titanium oxide. This reacts with most alloys that would not be candidates for the disk material in the embodiments described herein, but surprisingly, it was found that this behavior can be mitigated by controlling the amount of oxygen in both the disk material and the alloy being optimized. In one embodiment, the oxygen content of the predominant phase identified as titanium oxide (%Ti > 50 wt%) is preferably greater than 26 wt%. In another embodiment, the oxygen content of the predominant phase identified as titanium oxide (%Ti > 50 wt%) is preferably greater than 31 wt%. In another embodiment, the oxygen content of the predominant phase identified as titanium oxide (%Ti > 50 wt%) is preferably less than 39 wt%. In another embodiment, the oxygen content of the predominant phase identified as titanium oxide (%Ti > 50 wt%) is preferably less than 36 wt%. In another embodiment, the oxygen content of the predominant phase identified as titanium oxide (%Ti > 50 wt%) is preferably less than 34 wt%. In one embodiment, the oxygen content of the liquid to be nebulized is preferably 790 ppm by weight or less. In another embodiment, the oxygen content of the liquid to be nebulized is preferably 180 ppm by weight or less. In another embodiment, it is desirable for the liquid to be nebulized to have an oxygen content of 40 ppm by weight or less. In another embodiment, it is desirable for the liquid to be nebulized to have an oxygen content of 14 ppm by weight or less. In one embodiment, the absence of oxygen in the liquid to be nebulized is desirable.In one embodiment, TiN is preferably used as the disk material when the nitrogen content of the liquid material to be atomized is 1500 ppm by weight or less. In another embodiment, TiN is preferably used as the disk material when the nitrogen content of the liquid material to be atomized is 190 ppm by weight or less. In another embodiment, TiN is preferably used as the disk material when the nitrogen content of the liquid material to be atomized is 49 ppm by weight or less. In one embodiment, the disk material described in this paragraph is applied as a thick coating on a metallic material. In some embodiments, the atomizing rotor may be coated or uncoated, or may be partially coated or multi-coated. In some applications, a multi-layer coating is preferred. In one embodiment, the coating comprises at least two layers. In another embodiment, the coating comprises at least three layers. In some applications, the atomizing disk may be preferably coated with a material similar to the alloy to be atomized, or a stable component thereof, or a similar material, to improve wettability. This is of particular concern in some applications where greater wettability is preferred. The inventors have found that, regardless of the substrate material, the coating layer can be applied using different materials in some applications and can be effectively used as a coating material. In one embodiment, the atomization disk is at least partially coated with two or more coating layers of different composition. In some applications, a multi-layer coating consisting of a ceramic coating layer and a metallic coating layer is preferred, while in other applications, a multi-layer coating consisting of a metallic coating layer and a ceramic coating layer is preferred. In another embodiment, the first coating layer applied on the atomization disk is a metallic coating layer. Several coating techniques are suitable, including high velocity oxygen flame spraying (HVOF), chemical vapor deposition (CVD), physical vapor deposition (PVD), plasma spraying, thermal spraying or projection, low temperature gas spraying, cladding, fluidized bed, chemical or electrochemical techniques, and many other techniques. In one embodiment, the coating thickness is 2.1 microns or more. In another embodiment, the coating thickness is 8.1 microns or more.In another embodiment, the coating thickness is 22.1 microns or more. In another embodiment, the coating thickness is 72.1 microns or more. In another embodiment, the coating thickness is 103 microns or more. In another embodiment, the coating thickness is 160 microns or more. In another embodiment, the coating thickness is 280 microns or more. In another embodiment, the coating thickness is 370 microns or more. In another embodiment, the coating thickness is 560 microns or more. In another embodiment, the coating thickness is greater than 1.06 mm. In some applications, it is desirable for the coating thickness to be less than a certain value. In one embodiment, the coating thickness is less than 1.9 mm. In another embodiment, the coating thickness is less than 990 microns. In another embodiment, the coating thickness is less than 490 microns. In another embodiment, the coating thickness is less than 390 microns. In another embodiment, the coating thickness is less than 240 microns. In another embodiment, the coating thickness is less than 106 microns. In another embodiment, the coating thickness is less than 84 microns. In another embodiment, the coating thickness is less than 62 microns. In another embodiment, the coating thickness is less than 48 microns. All of the above embodiments may be combined with each other, provided they are not mutually exclusive. There are other combinations, such as a coating thickness of 2.1 microns or more and 990 microns or less. In an embodiment, if the coating comprises more than one layer, the thickness values ​​disclosed above refer to the thickness of each coating layer. In some embodiments, the above rules for iron-based alloys may be extended to magnesium-based alloys. In some embodiments, the above rules for iron-based alloys may be extended to lithium-based alloys. In some embodiments, the above rules for iron-based alloys may be extended to copper-based alloys. In some embodiments, the above rules for iron-based alloys may be extended to nickel-based alloys. In some embodiments, the above rules for iron-based alloys may be extended to cobalt-based alloys. In some embodiments, the above rules for iron-based alloys may be extended to titanium-based alloys.In some embodiments, the above rules for iron-based alloys may be extended to bronze-based alloys. In some embodiments, the above rules for iron-based alloys may be extended to metal-based alloys. In some embodiments, the above rules for iron-based alloys may be extended to non-magnetic metal-based alloys. In some embodiments, the method is also suitable for processing master alloys. The inventors have found that it is possible to produce such alloys when producing such master alloys at exceptionally low cost, with exceptionally low levels of microsegregation and exceptionally low levels of gas content (such as oxygen and nitrogen).

[0040] In some embodiments, direct contact of the powder being produced with the liquid, the liquid being atomized, etc., during all stages of atomization is highly detrimental, as it promotes the formation of intra-sphere voids, undesirable surface modifications, and in some embodiments, the formation of undesirable microstructures. In some embodiments, any kind of direct contact of the material being atomized (during any stage, including the liquid before atomization and the powder already atomized) with water or water-based fluids must be avoided. In some embodiments, any kind of direct contact of the material being atomized (during any stage of atomization) with any liquid must be avoided. In some embodiments, any kind of direct contact of the material being atomized (during any stage of atomization) with any contained liquid (such as mist) must be avoided. In some embodiments, contact of cooling liquid, mist, or other contained liquid with the rotating body must be avoided if it may come into contact with the material being atomized. In some embodiments, contact of the material being atomized with the cooling gas must be avoided when using large amounts of cooling gas, due to adverse environmental effects. In at least some applications, this can also adversely affect morphological or microstructural quality. In some embodiments, a recirculating gas is introduced into the spray chamber. In one embodiment, 990 m 3The introduction of any kind of circulating gas (introduced circulating gas is a gas which is injected into the spray chamber during the atomization process, even if it is in a closed circuit with, for example, a refrigeration or compression stage outside the chamber. The movement of the gas contained in the chamber is not considered as circulating gas in this aspect of the specification, even if it is done in an efficient way to reduce the temperature in the chamber using some heat exchange system) with a flow rate of 98 m / min or more must be avoided. In one embodiment, the introduction of any kind of circulating gas with a flow rate of 98 m / min or more ... 3 The introduction of any type of circulating gas with a flow rate of more than 48 m 3 The introduction of any type of circulating gas with a flow rate of more than 9 m 3 The introduction of any type of circulating gas with a flow rate of more than 4 m 3 The introduction of any type of circulating gas with a flow rate of more than 0.9 m3 / min must be avoided. 3The introduction of any kind of circulating gas with a flow rate of more than 10000 / min must be avoided. In some embodiments, the circulating gas introduced into the atomization chamber is a cooling gas. In some applications, an inert gas is suitable as a cooling gas. In some embodiments, the specific configurations of the present specification allow the use of a cooling gas curtain. However, for environmental reasons, an efficient circulation of a protective atmosphere gas in the chamber is suitable, allowing cooling by contact with a cold wall or a heat exchanger. In one embodiment, a part of the gas in the chamber is in contact with a cooling element (wall, or any kind of heat exchange system) that reduces the temperature of this part of the gas in the chamber by at least 2°C (the rotating body itself acting as an impeller or convection generated by local heating or cooling of the gas may be sufficient). In one embodiment, a part of the gas in the chamber is in contact with a cooling element that reduces the temperature of this part of the gas in the chamber by at least 6°C. In another embodiment, a part of the gas in the chamber is in contact with a cooling element that reduces the temperature of this part of the gas in the chamber by at least 12°C. In another embodiment, a portion of the gas in the chamber contacts a cooling element that reduces the temperature of the portion of the gas in the chamber by at least 22° C. In another embodiment, a portion of the gas in the chamber contacts a cooling element that reduces the temperature of the portion of the gas in the chamber by at least 52° C. In another embodiment, a portion of the gas in the chamber contacts a cooling element that reduces the temperature of the portion of the gas in the chamber by at least 122° C. In one embodiment, the gas contacts a cooling element that reduces its temperature by at least 1.2 m. 3 In another embodiment, the gas contacts a cooling element to reduce its temperature by at least 12 m / min. 3 In another embodiment, the gas contacts a cooling element to reduce its temperature by at least 120 m / min. 3 In another embodiment, the gas contacts a cooling element to reduce its temperature by at least 1200m / min. 3 In another embodiment, the gas contacts a cooling element to reduce its temperature by at least 12,000 m 3 / min. In one embodiment, the gas that is unavoidably in contact with the cooling element is an inert gas. In one set of embodiments, it may be considered to put a small amount of gas in the chamber to cool certain elements. In one set of embodiments, it may be considered to make this gas a liquid and a mist. In one set of embodiments, it is interesting that the fine particles in the mist constitute lubricating fluids or particles (oil, graphite microflakes, grease, etc.) if the elements addressed by the mist are bearings or other elements that benefit from lubrication. In one embodiment, the lubricating oil is oil. In one embodiment, the cooled element constitutes the bearing of the rotor that causes the atomization of the atomized material. In one embodiment, the cooled element constitutes the bearing closest to the atomization disk of the rotor that causes the atomization of the atomized material. In one embodiment, the cooled element constitutes the shaft of the main rotor that causes the atomization of the atomized material. In one embodiment, the cooled element constitutes the disk of the rotor that causes the atomization of the atomized material. In certain applications, the atomizing rotor may be cooled externally. In one embodiment, the amount of gas introduced for localized cooling of the atomizing device is 0.012 m 3 In another embodiment, the amount of gas introduced for localized freezing of the nebulizer is 0.12 m 3 In another embodiment, the amount of gas introduced for localized freezing of the nebulizer is 0.52 m 3 In another embodiment, the amount of gas introduced for localized freezing of the nebulizer is 1.2 m 3 In another embodiment, the amount of gas introduced for localized freezing of the nebulizer is 2.6 m 3 In another embodiment, the amount of gas introduced for localized freezing of the nebulizer is 6.6 m 3 In another embodiment, the amount of gas introduced for localized freezing of the nebulizer is 12 m 3 In one embodiment, the amount of gas introduced for localized freezing of the spray device is 98 m 3In another embodiment, the amount of gas introduced for localized freezing of the spray device is 48 m 3 In another embodiment, the amount of gas introduced for localized freezing of the spray device is 28 m 3 In another embodiment, the amount of gas introduced for localized freezing of the spray device is 9 m 3 In another embodiment, the amount of gas introduced for localized freezing of the spray device is 4 m 3 In another embodiment, the amount of gas introduced for localized freezing of the spray device is 1.9 m 3 In another embodiment, the amount of gas introduced for localized freezing of the spray device is 0.9 m 3 In one embodiment, the inventors have found that in order to obtain very fine spherical powders or particulate matter, it is preferable in some applications to carry out centrifugal atomization in an atomization chamber comprising an atomizing rotor in which the atmosphere within the atomization chamber is cooled.

[0041] The inventors have found that in some embodiments herein, it is important to follow an unconventional approach when designing the spray rotor (herein referred to as the disk). In these embodiments, only centrifugal forces are considered when performing the finite element simulation (FES), and all other acting forces on the disk are ignored. The stresses acting on all points of the disk are calculated using polar coordinates, and only radial components are considered. Within the radial components, only tensile stresses (and not compressive stresses) are considered. The stresses acting on all points of the disk are calculated using polar coordinates, and only radial components are considered. Within the radial components, only tensile stresses (and not compressive stresses) are considered. In one embodiment, the design is modified to have all radial tensile stresses on the disk due to centrifugal forces only less than 290 MPa. In another embodiment, the design is modified to have all radial tensile stresses on the disk due to centrifugal forces only less than 190 MPa. In another embodiment, the design is modified to have all radial tensile stresses on the disks with only centrifugal force less than 140 MPa. In another embodiment, the design is modified to have all radial tensile stresses on the disks with only centrifugal force less than 90 MPa. In another embodiment, the design is modified to have all radial tensile stresses on the disks with only centrifugal force less than 49 MPa. In another embodiment, the design is modified to have all radial tensile stresses on the disks with only centrifugal force less than 190 MPa. In another embodiment, the design is modified to have all radial tensile stresses on the disks with only centrifugal force less than 190 MPa. Interestingly, in some embodiments, in order to obtain non-porous particles with a narrow particle size distribution, the radial maximum FES tensile stress should not be too low. In one embodiment, the design is modified to have a maximum value of radial tensile stress on the disks with only centrifugal force greater than 14 MPa. In another embodiment, the design is modified to have a maximum radial tensile stress on the disk due to centrifugal force alone above 24 MPa. In another embodiment, the design is modified to have a maximum radial tensile stress on the disk due to centrifugal force alone above 44 MPa.In another embodiment, the design is modified so that the radial tensile stress on the disk due to the centrifugal force alone is greater than 84 MPa. In some applications, the inventors have found it preferable to use a special configuration. In this configuration, a metal structure is used around a ceramic disk (also called spinning, spinning disk, spinning disk atomization, atomizing disk, rotor, rotating disk or disk in some embodiments). The particularity is that the metal structure exerts a compressive load on the ceramic disk at the working condition. In one embodiment, the compressive load is achieved by selecting a metal material for the structure that has a lower thermal expansion coefficient than the material of the disk, with at least a part of the compressive load occurring due to the mismatch of thermal expansion coefficients when the temperature is increased to a steady state. In FIG. 2, an example of a possible configuration of disk and metal structure that exerts a compressive load when the working condition is achieved is shown. At point 1, an example of a ceramic disk with vane-like protrusions is depicted. At point 2, a support cage is depicted. At point 3, the insertion direction and point of the metal liquid to be atomized are depicted. Point 4 shows an example where the contact points between the cage and the disk provide a horizontal compressive load to the disk. In an embodiment, the cage is made of a material that elongates at break. In an embodiment, the gauge is made of a material that has an elongation at break of 0.8% or more at the processing temperature. In an embodiment, the elongation at break is measured at the processing temperature according to ASTM E21-17 (Standard Test Method for High Temperature Tensile Testing of Metallic Materials). In an embodiment, the cage is made of a metal. In an embodiment, the cage is a metallic structure. In an embodiment, there are contact points that provide a compressive load to the disk at least at the horizontal processing temperature. In an embodiment, there are contact points that provide a compressive load to the disk at least at the vertical processing temperature. In an embodiment, both the ceramic material and the material of the metal structure have similar thermal expansion coefficients, and the compressive load is achieved by mechanical interference when assembling the disk to the metal structure. If mechanical interference is present, the disk can be forcefully inserted into the structure.More often, however, the assembly is performed with a temperature differential between the disk and the hotter metal structure such that when both materials reach room temperature (defined herein as 23±2°C), the mechanical interference is reached. In one embodiment, the stress in the ceramic disk between the ceramic disk and the metal structure is greater than the LFC. * σ creeep Less than, LSC * σ creeep In another embodiment, LFC is 1. In another embodiment, LFC is 0.8. In another embodiment, LFC is 0.6. In another embodiment, LFC is 1.2. In another embodiment, LFC is 0.4. In another embodiment, LFC is 0.7. In another embodiment, LFC is 0.5. In another embodiment, LFC is 0.3. In another embodiment, LFC is 0.1. In another embodiment, LFC is 0.01. In one embodiment, σ creep is the 10 hour creep resistance of a metallic material at the steady-state processing temperature. creep is the 1000 hour creep resistance of a metallic material at the steady-state processing temperature. creep is the 10,000 hour creep resistance of a metallic material at the steady-state processing temperature. creep is the creep resistance of a metallic material at 800° C. for 10 hours. creep is the creep resistance of a metallic material at 800° C. for 1000 hours. creep is the creep resistance of a metallic material at 1000° C. for 10 hours. creep is the creep resistance of a metallic material at 1000° C. for 1000 hours. creep is the creep resistance of a metallic material at 1200° C. for 10 hours. creep is the creep resistance of a metallic material at 1200° C. for 1000 hours. creep is the creep resistance of a metallic material at 1400° C. for 10 hours. creepis the creep resistance of a metallic material at 1400° C. for 1000 hours. creep is the creep resistance of a metallic material at 1600° C. for 10 hours. creep is the creep resistance of a metallic material at 1600° C. for 1000 hours. In one embodiment, the creep resistance of a metallic material (σ creep ) is measured according to ASTM E139-11(2018). In another embodiment, the creep resistance (σ creep ) is measured according to ISO 204:2018(en). In one embodiment, σ creep In another embodiment, a material having a σ of 12 MPa or more at the processing temperature is used. creep In another embodiment, a material having a σ of 26 MPa or more at the processing temperature is used. creep In another embodiment, a material having a σ of 52 MPa or more at the processing temperature is used. creep In another embodiment, a material having a σ of 72 MPa or more at the processing temperature is used. creep In another embodiment, a material having a σ of 110 MPa or more at the processing temperature is used. creep In another embodiment, a material having a σ of 280 MPa or more at the processing temperature is used. creep Materials having a thermal stress of 620 MPa or more are employed. In one embodiment, FEM simulations are used to determine the stress in the ceramic disk at the interface between the ceramic disk and the metal structure. In one embodiment, FEM simulations are used to determine the steady-state processing temperature of the interface between the ceramic disk and the metal structure. In some embodiments, the stress at the interface between the ceramic disk and the metal structure is determined as follows: [e 0 +(a ceramic -a metal ) * (T work -295) * (E ceramic +E metal ) / 2] where: a ceramic Ceramic room temperature to T work Average thermal expansion coefficient up to a metalMetal room temperature to T work Average thermal expansion coefficient up to T work Steady-state regime processing temperature in Kelvin E ceramic Room temperature to T work Average elastic modulus of ceramics up to E metal Room temperature to T work Average elastic modulus of metals up to In one embodiment, the elastic modulus of a metal is measured according to ASTM E8 / E8M-16a (Standard Test Method for Tensile Testing of Metallic Materials) and High Temperature (T work ) at room temperature in accordance with ASTM E21-17.

[0042] In one embodiment, the elastic modulus of the ceramic is determined according to ASTM C1161-18 (Standard Test Method for Flexural Strength of Fine Ceramics at Ambient Temperature) and High Temperature (T work ) is measured at room temperature in accordance with ASTM C1211-18 (Standard Test Method for High Temperature Flexural Strength of Fine Ceramics).

[0043] In one embodiment, the coefficient of thermal expansion is measured according to ASTM E831-14, Standard Test Method for Linear Thermal Expansion of Solid Materials by Thermomechanical Analysis.

[0044] In one embodiment, the processing temperature is the temperature of the molten composition. In one embodiment, the processing temperature is the temperature of the molten composition in contact with the spray rotor. In one embodiment, the processing temperature is the temperature of the spray rotor. In one embodiment, the temperature of the spray rotor is measured directly. In another embodiment, the temperature of the spray rotor is calculated using FEM. In another embodiment, the temperature of the spray rotor is calculated by measuring the temperature of multiple points on the rotor surface in contact with the molten composition and averaging the average or arithmetic mean value. In another embodiment, the temperature of the spray rotor is calculated by measuring the temperature of multiple points on the rotor surface in contact with the molten composition and averaging the maximum value. In another embodiment, the processing temperature refers to Tm, Tm-25, Tm-60, Tm-100, Tm-160, Tm-200, Tm-270, Tm-350 or Tm-470, where Tm is the melting point of the composition to be sprayed in degrees Celsius. In another embodiment, the processing temperature refers to Tm+40, Tm+120, Tm+160, Tm+220, or Tm+300, where Tm is the melting point of the composition to be sprayed in degrees Celsius (°C). In one embodiment, where the steady processing temperature is the temperature of the atomizing rotor in a steady operation mode. In one embodiment, where the steady processing temperature is the temperature of the molten composition. In one embodiment, where the steady processing temperature is the temperature of the molten composition in contact with the atomizing rotor. In one embodiment, the steady processing temperature of the atomizing rotor is measured directly. In another embodiment, the steady processing temperature of the atomizing rotor is calculated using FEM. In another embodiment, the temperature of the atomizing rotor is calculated by measuring the temperature at multiple points on the rotor surface and averaging the measured values ​​by the average or arithmetic mean value. In another embodiment, the temperature of the atomizing rotor is calculated using FEM. In another embodiment, the steady-state processing temperature of the spray rotor is calculated by measuring the temperatures at multiple points on the rotor surface in contact with the molten composition and averaging the average or arithmetic average value. In another embodiment, the temperature of the spray rotor is calculated by measuring the temperatures at multiple points on the rotor surface in contact with the molten composition and averaging the maximum value.In some other embodiments, the steady-state processing temperature refers to Tm, Tm-25, Tm-60, Tm-100, Tm-160, Tm-200, Tm-270, Tm-350 or Tm-470, where Tm is the melting point of the composition to be sprayed in degrees Celsius (°C). In other embodiments, the steady-state processing temperature refers to Tm+40, Tm+120, Tm+160, Tm+220 or Tm+300, where Tm is the melting point of the composition to be sprayed in degrees Celsius (°C).

[0045] The atomizing rotor is an element for performing atomization of the molten composition (also called melt). In one embodiment, the molten composition refers to a molten material, a molten alloy, or a molten metal. The inventors have found that in some embodiments, the molten composition can include a solid fraction. In one embodiment, the inventors have found that it is desirable for the solid fraction in the molten composition to be less than 79 wt%. In another embodiment, it is preferable for the solid fraction in the molten composition to be low. In one embodiment, the solid fraction in the molten composition is less than 39 wt%. In another embodiment, the solid fraction in the molten composition is less than 19 wt%. In another embodiment, the solid fraction in the molten composition is less than 9 wt%. In another embodiment, the solid fraction in the molten composition is less than 4 wt%. In another embodiment, the solid fraction in the molten composition is less than 0.4 wt%. In contrast, in some applications, it is desirable to have a minimum solid fraction in the molten composition. In one embodiment, the solid fraction in the molten composition is greater than 0.01 wt%. In another embodiment, the solid fraction in the molten composition is greater than 0.1 wt%. In another embodiment, the solid fraction in the molten composition is greater than 1.2 wt%. In another embodiment, the solid fraction in the molten composition is greater than 6 wt%. In another embodiment, the solid fraction in the molten composition is greater than 10.6 wt%. In some situations, the atomizing rotor is referred to as a rotating disk, atomizing disk, spinning, spinning disk, spinning disk atomizer, disk section, or rotor, but includes the operation of any other atomizing rotor shape. Examples include flat disks, cups, cones, inverted cones, and other suitable shapes. In some applications, the inventors have found that it is desirable for the atomizing rotor to be a one-piece bulk disk. In other applications, the atomizing rotor includes different parts made of different materials. In some applications, the inventors have found that it is necessary to operate a specific configuration. In this setup, for some applications it is desirable for the metallic atomizer disk and main shaft to be fabricated as one piece (monolithic metallic atomizer disk and main shaft) (an example is shown in Figure 4(b)).Regarding the assembly of the atomizing rotor, the inventors have found that in some embodiments using a monolithic atomizing disk set-up provides additional advantages for the production of metal powders. In some applications, the atomizing part is mounted integrally, resulting in a lighter atomizing part. Furthermore, in some applications, the process of dynamically balancing the atomizing part is found to be simpler and less costly. The inventors have found that under such a configuration, in some cases, the production of metal powders can be effectively performed, and the produced powders exhibit lower particle size and improved morphology values ​​in terms of sphericity. Furthermore, in some applications, the inventors also highlight the lower cost and greater feasibility of such a configuration. In relation to the material, in another embodiment, ceramics or metals, among other materials, are desired for the atomizing rotor. As mentioned above, in some embodiments, the atomizing rotor may be coated or uncoated, or may be partially coated. In another embodiment, the coating is preferably metal or ceramic, among other materials. In some embodiments, it is advantageous to have protrusions, such as vanes, ridges or projections, on the surface of the atomizing rotor, which has a constant cross-sectional area and a predetermined extrusion path through which the liquid metal can flow and form a channel or guide. With regard to the distribution of protrusions on the surface of the atomizing rotor, in some embodiments, the inventors have found that it is preferable that at least some of the protrusions are axially asymmetric. In some embodiments, the protrusions are vanes. The distribution of vanes on the atomizing rotor can affect the performance of the atomizing rotor. The inventors have found that in some embodiments, radially distributed vanes are preferable. On the other hand, in some embodiments, vanes that are not radially distributed are preferable. In some embodiments, a minimum diameter of the atomizing rotor (spray disk) is preferable. In one embodiment, the diameter of the spray disk is 36 mm or more. In another embodiment, the diameter of the spray disk is 46 mm or more. In another embodiment, the diameter of the spray disk is 56 mm or more. In another embodiment, the diameter of the spray disk is 76 mm or more. In another embodiment, the diameter of the spray disc is 86 mm or greater.In another embodiment, the diameter of the spray disk is 106 mm or more. In another embodiment, the diameter of the spray disk is 202 mm or more. In another embodiment, the diameter of the spray disk is 216 mm or more. In another embodiment, the diameter of the spray disk is 306 mm or more. The inventors have found that in various applications, a spray disk that is too large can lead to surprisingly unfavorable results in terms of the morphological quality of the powder, especially when examining the interior of the powder. In one embodiment, it is desirable for the diameter of the spray disk to be less than 690 mm. In another embodiment, it is desirable for the diameter of the spray disk to be less than 490 mm. In another embodiment, it is desirable for the diameter of the spray disk to be less than 290 mm. In another embodiment, it is desirable for the diameter of the spray disk to be less than 190 mm. In another embodiment, regardless of the shape of the atomizing disk, which is preferably less than 90 mm in diameter, in some applications, or even in some applications where the thickness profile is changed, the distribution of the liquid metal is promoted by the action of a certain number of vanes of variable involute or involute type shape. The vanes can present single or double curvatures and can have any geometric arrangement suitable for the atomization purpose. The inventors have found that in some applications, straight projections or vanes are preferred. In one embodiment, the vanes are radial straight vanes. In other applications, curved vanes are preferred. In another embodiment, the vanes are preferably backward curved, more preferably radially curved, and more preferably forward curved. In addition, it has been found that in some applications, better atomization results are obtained when the cross section of the vane does not have straight edges or segments. This is particularly worthy of consideration in some applications, where the number of vanes is preferably six or more and the vanes are straight radial vanes. In another embodiment, vanes of variable shape and variable cross-sectional shape are preferred. In another embodiment, the cross section of the vane is preferably triangular, square, trapezoidal, among others, having straight edges or segments. Additionally, in some applications, providing a serrated edge on the outer periphery of the atomizing rotor is desirable to promote a more uniform droplet size distribution and improve the quality of the atomization process.This must be clearly distinguished from completely different existing methods that employ blades, cutters, windows or other types of protrusions to implement a grinding effect for material breakup. In one embodiment, the main effect of the protrusions is the velocity imparted to the metal liquid, not the grinding effect.

[0046] A thorough literature review conducted by the inventors has revealed that centrifugal atomization using atomization disks of refractory metals appears to be incompatible with mass production, possibly due to the expected degradation of powder morphological quality. This appears to be exacerbated when having axially asymmetric vanes on the atomization disk. The inventors were surprised to find that mass production of sonomorphic quality of refractory metals and alloys is possible. Even more surprising was the discovery that this is possible with large scale atomization disks incorporating axially asymmetric protrusions or vanes. In one embodiment, the mass production batch is 6 kg or more. In another embodiment, the mass production batch is 12 kg or more. In another embodiment, the mass production batch is 60 kg or more. In another embodiment, the mass production batch is 120 kg or more. In another embodiment, the mass production batch is 600 kg or more. In another embodiment, the mass production batch is 1200 kg or more. In fact, and surprisingly, when processed under the optimized conditions described herein, very large scale production can be achieved and the sound morphological quality of the atomized powder can be maintained. In one embodiment, the batch size is 2100 kg or more. In another embodiment, the batch size is 6000 kg or more. In another embodiment, the batch size is 16000 kg or more. In another embodiment, the batch size is 21000 kg or more. In another embodiment, the batch size is 80000 kg or more. In one embodiment, the high melting point metal or alloy refers to a metal or alloy that exhibits a melting point of 660° C. or more. In another embodiment, the high melting point metal or alloy refers to a metal or alloy that exhibits a melting point of 1020° C. or more. In another embodiment, the high melting point metal or alloy refers to a metal or alloy that exhibits a melting point of 1210° C. or more. In another embodiment, the high melting point metal or alloy refers to a metal or alloy that exhibits a melting point of 1450° C. or more. In one embodiment, the large scale spray disk refers to a spray disk having a diameter of 36 mm or more. In another embodiment, the large scale spray disk refers to a spray disk having a diameter of 46 mm or more. In another embodiment, the large scale spray disk refers to a spray disk having a diameter of 56 mm or more. In another embodiment, the large scale spray disk refers to a spray disk having a diameter of 76 mm or more.In another embodiment, the large scale spray disk herein refers to a spray disk having a diameter of 106 mm or more. In another embodiment, the large scale spray disk herein refers to a spray disk having a diameter of 202 mm or more. In another embodiment, the large scale spray disk herein refers to a spray disk having a diameter of 216 mm or more. In another embodiment, the large scale spray disk herein refers to a spray disk having a diameter of 306 mm or more. The inventors have found that in many applications, excessively large disks can lead to surprisingly undesirable results in terms of powder morphology quality, especially when the powder is examined internally. In one embodiment, it is desired that the spray disk diameter is less than 990 mm. In another embodiment, it is desired that the spray disk diameter is less than 690 mm. In another embodiment, it is desired that the spray disk diameter is less than 490 mm. In another embodiment, it is desired that the spray disk diameter is less than 290 mm. In another embodiment, the diameter of the spray disk is desired to be less than 190 mm. In another embodiment, the diameter of the spray disk is desired to be less than 90 mm. Often, from an economic point of view, productivity is more relevant than the size of the production batch. However, according to the literature, this is at least as difficult as with high melting point alloys. The literature describes different steps that are often necessary to combine for different alloys in order to achieve unexpected large batch productivity. In one embodiment, the large batch productivity is 32 kg / h or more. In another embodiment, the large batch productivity is 89 kg / h or more. In another embodiment, the large batch productivity is 102 kg / h or more. In another embodiment, the large batch productivity is 322 kg / h or more. In another embodiment, the large batch productivity is 512 kg / h or more. In another embodiment, the large batch productivity is 1020 kg / h or more. In another embodiment, the large batch productivity is 2680 kg / h or more. In another embodiment, the large batch productivity is greater than 3200 kg / h. In some applications, the maximum large batch productivity is limited. In one embodiment, the large batch productivity is less than 19400 kg / h.In another embodiment, the large scale batch productivity is 6940 kg / h or less. In another embodiment, the large scale batch productivity is 4490 kg / h or less. In another embodiment, the large scale batch productivity is 2440 kg / h or less. In another embodiment, the large scale batch productivity is 1440 kg / h or less.

[0047] One of the most interesting and unexpected observations made by the inventors is the effect of wettability of the atomizing liquid on the atomizing disk surface. In this regard, the inventors have made several observations in selecting different disk materials, different coatings, and different methods of texturing the working surface of the atomizing disk, or at least a portion thereof. In one embodiment, at least a portion of the disk surface is textured in order to change the wettability of the atomizing liquid on the atomizing disk. In one embodiment, the surface modification increases the wettability. In one embodiment, the surface modification provides superhydrophilicity. In one embodiment, the surface modification provides a contact angle between the molten metal and the modified surface of less than 89°. In another embodiment, the surface modification provides a contact angle between the molten metal and the modified surface of less than 64°. In another embodiment, the surface modification provides a contact angle between the molten metal and the modified surface of less than 38°. In another embodiment, the surface modification provides a contact angle between the molten metal and the modified surface of less than 22°. In another embodiment, the surface modification results in a contact angle between the molten metal and the modified surface of less than 9°. In another embodiment, the surface modification results in a contact angle between the molten metal and the modified surface of less than 4°. In one embodiment, the surface modification provides hydrophobicity. In one embodiment, the surface modification provides superhydrophobicity. In one embodiment, the surface modification provides a contact angle between the molten metal and the modified surface of 95°. In another embodiment, the surface modification provides a contact angle between the molten metal and the modified surface of 105°. In another embodiment, the surface modification provides a contact angle between the molten metal and the modified surface of 145°. In another embodiment, the surface modification provides a contact angle between the molten metal and the modified surface of 155°. In another embodiment, the surface modification provides a contact angle between the molten metal and the modified surface of 165°. In another embodiment, the surface modification provides a contact angle between the molten metal and the modified surface of 175°. In one embodiment, the surface modification results in a contact angle hysteresis between the molten metal and the modified surface of less than 25°. In one embodiment, the surface modification results in a contact angle hysteresis between the molten metal and the modified surface of less than 15°. In one embodiment, the surface modification results in a contact angle hysteresis between the molten metal and the modified surface of less than 9°. In one embodiment, the surface modification results in a contact angle hysteresis between the molten metal and the modified surface of less than 4°.In one embodiment, the surface modification results in a contact angle hysteresis between the molten metal and the modified surface of less than 0.9°. In this paragraph and elsewhere herein, unless otherwise noted, wettability values ​​are quantified by the internal contact angle between the liquid and the solid surface. In one embodiment, the texturing is performed by engraving with a mold. In one embodiment, the texturing is performed by engraving with a repeating mold. In one embodiment, the texturing is performed by engraving with a random mold. In one embodiment, the texturing is performed by etching. In one embodiment, the texturing is performed by painting. In one embodiment, the texturing is performed by a laser light source. In one embodiment, the texturing is performed by an electron beam source. In one embodiment, the texturing is performed by laser engraving.

[0048] The inventors have found that, with regard to the number of protrusions such as vanes, it is advantageous to have 2 vanes, more preferably 2 vanes, more preferably 3 vanes, even more preferably 5 vanes in a radial geometric arrangement or other suitable arrangement suitable for the purpose of atomization. The inventors have found that in some applications it is preferred that the number of vanes of the atomizing rotor is at least 5, more preferably at least 7, even more preferably at least 15. In some applications using linear radial vanes, better results are obtained if the number of vanes is more than 6, preferably more than 9, even more preferably more than 11, even more preferably more than 15. The above-mentioned embodiments of the vanes are applicable to all protrusions.

[0049] The inventors have found that it is also possible to produce metal powders by atomizing liquid metals by pouring them onto a superhydrophobic surface. By adjusting the texture and properties of the material where the liquid flow is interrupted, the pressure, the heating of the liquid, the atmosphere, etc., the morphology of the resulting powder, such as particle size and sphericity, can be effectively controlled. Other process variables also have an effect, but the ones described are often sufficient for a particular morphology and size distribution. The values ​​mentioned above for the contact angle and contact angle hysteresis can be adopted in this case as well. In this case, it has been found that the pitch of the texture pattern is important, since in many cases it determines the average particle size achieved in the atomization process. In this case, the pitch becomes the critical distance of the pattern. In one embodiment, the critical distance of the pattern is the minimum distance between two adjacent topological relative extremes (two maxima or minima) of the same sign. In one embodiment, the critical distance of the pattern is the minimum distance between two adjacent topological relative extremes (peaks of a maximum and valleys of a minimum) of opposite signs. In one embodiment, the critical distance of a regular mould is the smallest distance between two identical points in the mould. In one embodiment, the pitch is preferably 9 mm or less. In one embodiment, the pitch is preferably 0.9 mm or less. In one embodiment, the pitch is preferably 740 microns or less. In one embodiment, the pitch is preferably 450 microns or less. For the production of very fine powders, and when all other relevant properties are taken into account, especially those that affect the surface tension, it has been proven to be very effective to have very small pitch values. In one embodiment, the pitch is preferably 190 microns or less. In another embodiment, the pitch is preferably 90 microns or less. In another embodiment, the pitch is preferably 40 microns or less. In another embodiment, the pitch is preferably 19 microns or less. In another embodiment, the pitch is preferably 9 microns or less. In another embodiment, the pitch is preferably 4 microns or less. Even sub-micron pitches should be considered. In another embodiment, the pitch is preferably 900 nanometers or less. In another embodiment, it is desirable for the pitch to be 690 nanometers or less.In another embodiment, it is desirable for the pitch to be 390 nanometers or less.In another embodiment, it is desirable for the pitch to be 90 nanometers or less.

[0050] The inventors have surprisingly found that the nature of the bearing configuration that allows the disk to rotate relative to the structure that supports it in the desired position has a fairly significant effect on the quality of the powder produced, especially the morphology, and this effect is very significant in the case of large batches. The inventors have found that in some embodiments, when the aforementioned limitations are used, the cost of powder production can be reduced due to an increase in the service life of the atomization system. Although the characteristics in terms of rotation speed and load can be achieved in a large number of configurations, the number that can consistently produce a stable morphological quality in large batches is surprisingly limited. In some instances, the design configuration is the most critical. In one embodiment, the aforementioned limitations apply to all bearings on the main shaft (the shaft that has the disk at one end and is responsible for rotating the disk while keeping it in the desired position). In one embodiment, the aforementioned limitations apply to the two bearings on the main shaft that are closest to the disk. In one embodiment, the aforementioned limitations apply to the bearings on the main shaft that are closest to the disk. In one embodiment, the aforementioned limitations apply to all bearings on the main shaft that are 990 mm or less away from the atomization disk. In another embodiment, the aforementioned limit applies to all main shaft bearings that are 490 mm or less away from the spray disk. In another embodiment, the aforementioned limit applies to all main shaft bearings that are 290 mm or less away from the spray disk. In another embodiment, the aforementioned limit applies to all main shaft bearings that are 190 mm or less away from the spray disk. In another embodiment, the aforementioned limit applies to all main shaft bearings that are 90 mm or less away from the spray disk. In another embodiment, the aforementioned limit applies to all main shaft bearings that are 38 mm or less away from the spray disk.

[0051] In one embodiment, the limit applies to a bearing with angular contact. In one embodiment, the limit applies to a bearing with angular contact with a contact angle of 12° or more. In another embodiment, the limit applies to a bearing with angular contact with a contact angle of 15.5° or more. In another embodiment, the limit applies to a bearing with angular contact with a contact angle of 16.5° or more. In another embodiment, the limit applies to a bearing with angular contact with a contact angle of 18° or more. In another embodiment, the limit applies to a bearing with angular contact with a contact angle of 21° or more. In one embodiment, the limit applies to a bearing with angular contact with a contact angle of 34° or less. In another embodiment, the limit applies to a bearing with angular contact with a contact angle of 29° or less. In one embodiment, the limit applies to a bearing with angular contact with a contact angle of 25.5° or less. In one embodiment, the bearing to which the restriction applies is a bearing with angular contact with a contact angle of 19° or less. In one embodiment, the bearing to which the restriction applies is a bearing with gradual angular contact that allows for a reduction in the space between the outer ring (referred to herein as a ring) and the outer diameter of the inner ring (e.g., due to shaft expansion). The allowing for the reduction in space is achieved by relative radial displacement between the inner and outer raceways, which still allows the bearing to operate. In one embodiment, the available space between the outer diameter of the outer ring and the inner ring can be reduced by 0.06 mm or more. In another embodiment, the available space between the outer diameter of the outer ring and the inner ring can be reduced by 0.12 mm or more. In another embodiment, the available space between the outer diameter of the outer ring and the inner ring can be reduced by 0.26 mm or more. In another embodiment, the available space between the outer diameter of the outer ring and the inner ring can be reduced by 0.6 mm or more. In another embodiment, the available space between the outer diameter of the outer ring and the inner ring can be reduced by 1.2 mm or more. In one embodiment, the relative radial offset between the inner and outer rings can be 3 mm or more.In another embodiment, the relative radial deviation between the inner ring and the outer ring can be 1.2 mm or more. In another embodiment, the relative radial deviation between the inner ring and the outer ring can be 2.1 mm or more. In another embodiment, the relative radial deviation between the inner ring and the outer ring can be 5.2 mm or more. In one embodiment, the bearing to which the limit is applied is a bearing with a cylindrical rotating body. In one embodiment, the bearing to which the limit is applied is a bearing with a ball rotating body. In one embodiment, the bearing to which the limit is applied is a bearing with a ceramic rotating body. In one embodiment, the bearing to which the limit is applied is a bearing with a high-temperature performance metal ring (both the inner ring and the outer ring are in contact with the rotating body bearing). In one embodiment, the bearing to which the limit is applied is a bearing with a high-temperature resistant metal outer ring. In one embodiment, the high-temperature resistant metal material refers to a metal material or alloy that has high hardness at room temperature even when exposed to high temperatures for a long period of time. In one embodiment, the high heat resistant metallic material is a metallic material or alloy that has high temperature hardness even when exposed to this high temperature for a long time. In one embodiment, the high hardness is 54HRc or more. In another embodiment, the high hardness is 58HRc or more. In another embodiment, the high hardness is 62HRc or more. In another embodiment, the high hardness is 64HRc or more. In another embodiment, the high hardness is 67HRc or more. In one embodiment, the room temperature hardness is measured according to ASTM E18-18a (Standard Test Method for Rockwell Hardness of Metallic Materials). In one embodiment, the long exposure is 35 minutes or more. In another embodiment, the long exposure is 1.2 hours or more. In another embodiment, the long exposure is 5.2 hours or more. In another embodiment, the long exposure is 12 hours or more. In another embodiment, the long exposure is 22 hours or more. In another embodiment, the long term exposure is 110 hours or more. In some applications, it may be desirable to limit the exposure time to a certain amount of time or less. In one embodiment, the long term exposure is 220 hours or less. In another embodiment, the long term exposure is 90 hours or less. In another embodiment, the long term exposure is 28 hours or less. In one embodiment, the high exposure temperature is 85° C. or more. In another embodiment, the high exposure temperature is 105° C. or more. In another embodiment, the high exposure temperature is 155° C. or more.In another embodiment, the high exposure temperature is 255°C or higher. In another embodiment, the high exposure temperature is 375°C or higher. In another embodiment, the high exposure temperature is 485°C or higher. In one embodiment, it is desirable to limit the high exposure temperature to a certain value or lower. In one embodiment, the high exposure temperature is 840°C or lower. In another embodiment, the high exposure temperature is 585°C or lower. In another embodiment, the high exposure temperature is 245°C or lower. In some applications, it has been found to be effective to operate a high exposure temperature resistant lubricant in the bearings to which the limit applies. In one embodiment, the bearings to which the limit applies are comprised of a lubricant having a high maximum operating temperature. In one embodiment, the lubricant is continuously applied to the bearings. In one embodiment, the continuity of application of the lubricant consists of pulses of application and time that elapses without application of new lubricant. In one embodiment, the maximum operating temperature of the lubricant is 86°C or higher. In another embodiment, the maximum lubricant use temperature is 112°C or more. In another embodiment, the maximum lubricant use temperature is 186°C or more. In another embodiment, the maximum lubricant use temperature is 256°C or more. In another embodiment, the maximum lubricant use temperature is 306°C or more. In one embodiment, the outer ring of the bearing to which the restriction applies is flexible. In one embodiment, the inner ring of the bearing to which the restriction applies is outside the processing tolerance at room temperature, but is within the processing tolerance at processing temperature. In one embodiment, the shaft and the disk connecting at least a portion of the bearing to which the restriction applies are made of a low thermal conductivity material. In one embodiment, the low thermal conductivity material is made of a metal or metal alloy. In one embodiment, the low thermal conductivity is 90 W / mK or less. In another embodiment, the low thermal conductivity is 34 W / mK or less. In another embodiment, the low thermal conductivity is 24 W / mK or less. In another embodiment, the low thermal conductivity is 19 W / mK or less. In another embodiment, the low thermal conductivity is 9 W / mK or less. In one embodiment, the thermal conductivity refers to the thermal conductivity measured at room temperature (as elsewhere in this specification unless otherwise specified). In one embodiment, the thermal conductivity is measured according to ASTM E1461-13 (Standard Test Method for Thermal Diffusivity by Flash Method). This method can be used to measure thermal conductivity at room temperature and at nominal use temperatures.The method can be used to measure thermal conductivity at room temperature and at a reference operating temperature. In an embodiment, some cooling is applied around at least one of the bearings to which the restriction applies. In an embodiment, some cooling is applied around at least one of the bearings to which the restriction applies. In an embodiment, the cooling is applied directly to the shaft on which the bearing is mounted. In an embodiment, the cooling medium is comprised of a phase that changes upon contact with the hot surface to be cooled. In an embodiment, the phase change comprises evaporation. In an embodiment, the phase change comprises sublimation.

[0052] In one embodiment, the reference processing temperature is the theoretical temperature of the atomizing rotor. In one embodiment, the reference processing temperature is the temperature of the molten composition. In one embodiment, the reference processing temperature is the temperature of the molten composition in contact with the atomizing rotor. In one embodiment, the reference processing temperature is the temperature of the atomizing rotor. In one embodiment, the reference processing temperature of the atomizing rotor is calculated using FEM. In another embodiment, the reference processing temperature of the atomizing rotor is calculated as the average or arithmetic mean value of the temperature over several points on the surface of the rotor in contact with the molten composition. In another embodiment, the reference processing temperature of the atomizing rotor is calculated as the maximum value of the temperature of several points on the surface of the rotor in contact with the molten composition. The reference processing temperature refers to the melting temperature of the composition to be sprayed. In another embodiment, the reference processing temperature refers to Tm, Tm-25, Tm-60, Tm-100, Tm-160, Tm-200, Tm-270, Tm-350, or Tm-470, where Tm is the melting temperature of the composition being sprayed in degrees Celsius. In another embodiment, the reference processing temperature refers to Tm+40, Tm+120, Tm+160, Tm+220, or even Tm+300, where Tm is the melting temperature of the composition being sprayed in degrees Celsius (°C).

[0053] Using the techniques described herein, it is possible to obtain surprisingly low levels of certain elements that are in gaseous form under normal conditions (herein, normal conditions refer to 20° C. and 1 atm). Surprisingly, these low levels result in unexpected behavior of the powders related to mechanical properties, especially ductility. In one embodiment, the powder has an oxygen content of 490 ppm or less by weight. In another embodiment, the powder has an oxygen content of 290 ppm or less by weight. In another embodiment, the powder has an oxygen content of 190 ppm or less by weight. In another embodiment, the powder has an oxygen content of 90 ppm or less by weight. In another embodiment, the powder has an oxygen content of 44 ppm or less by weight. Special treatments can keep the oxygen levels at surprisingly low levels. In one embodiment, the powder has an oxygen content of 24 ppm or less by weight. In one embodiment, the powder has an oxygen content of 19 ppm or less by weight. In one embodiment, the powder has an oxygen content of 14 ppm or less by weight. In one embodiment, the powder has an oxygen content of 9 ppm or less by weight. In one embodiment, the powder has an oxygen content of 4 ppm or less by weight. In one embodiment, the powder has an oxygen content of 0.09 ppm or less by weight. In another embodiment, the above is by volume. In contrast, in some applications, low levels of oxygen are preferred. In one embodiment, the oxygen content is 3 ppm or more by weight. In one embodiment, the oxygen content is 64 ppm or more by weight. In one embodiment, the oxygen content is 108 ppm or more by weight. In another embodiment, the above is by volume. In one embodiment, the powder or particulate has a nitrogen content of 490 ppm or less by weight. In another embodiment, the powder or particulate has a nitrogen content of 190 ppm or less by weight. In another embodiment, the powder or particulate has a nitrogen content of 90 ppm or less by weight. In another embodiment, the nitrogen content of the powder or particulate is 40 ppm by weight or less. In another embodiment, the nitrogen content of the powder or particulate is 18 ppm by weight or less. In another embodiment, the nitrogen content of the powder or particulate is 4 ppm by weight or less. In some applications, low levels of nitrogen content are preferred. In one embodiment, the nitrogen content is greater than 2 ppm by weight.In another embodiment, the nitrogen content is greater than 48 ppm by weight. In another embodiment, the nitrogen content is greater than 103 ppm by weight. In another embodiment, the above is by volume. In an embodiment, the hydrogen content of the powder is less than or equal to 1.8 ppm by weight. In another embodiment, the hydrogen content of the powder is less than or equal to 0.9 ppm by weight. In another embodiment, the hydrogen content of the powder is less than or equal to 0.4 ppm by weight. In another embodiment, the hydrogen content of the powder is less than or equal to 0.09 ppm by weight. In another embodiment, the hydrogen content of the powder is less than or equal to 0.009 ppm by weight. In another embodiment, the above is by volume. In an embodiment, the above also applies to iron. In an embodiment, the above also applies to iron alloys. In an embodiment, the above also applies to iron-based alloys. In an embodiment, the above also applies to steel. In some embodiments, the above also applies to tool steels. In some embodiments, the above also applies to hot work tool steels. In some embodiments, the above also applies to titanium. In some embodiments, the above also applies to titanium alloys. In some embodiments, the above also applies to titanium-based alloys. In some embodiments, the above also applies to nickel. In some embodiments, the above also applies to nickel alloys. In some embodiments, the above also applies to nickel-based alloys. In some embodiments, the above also applies to aluminum. In some embodiments, the above also applies to aluminum alloys. In some embodiments, the above also applies to aluminum-based alloys. In some embodiments, the above also applies to magnesium. In some embodiments, the above also applies to magnesium alloys. In some embodiments, the above also applies to magnesium-based alloys. In some embodiments, the above also applies to lithium. In some embodiments, the above also applies to lithium alloys. In some embodiments, the above also applies to lithium-based alloys. In some embodiments, the above also applies to copper. In some embodiments, the above also applies to copper alloys. In some embodiments, the above also applies to copper-based alloys.In some embodiments, the above also applies to cobalt. In some embodiments, the above also applies to cobalt alloys. In some embodiments, the above also applies to cobalt-based alloys. In some embodiments, once the metal is molten and in the pre-atomization stage, a vacuum of 9 mbar or more is applied. In another embodiment, once the metal is molten and in the pre-atomization stage, a vacuum of 0.9 mbar or more is applied. In another embodiment, once the metal is molten and in the pre-atomization stage, a vacuum of 0.09 mbar or more is applied. In another embodiment, once the metal is molten and in the pre-atomization stage, a vacuum of 0.009 mbar or more is applied. In another embodiment, once the metal is molten and in the pre-atomization stage, a vacuum of 0.00009 mbar or more is applied. In some embodiments, after the vacuum is applied, the chamber is supplemented with an inert atmosphere before atomization begins. In some embodiments, the inert atmosphere consists of an inert gas. In one embodiment, an atmosphere with controlled oxygen content is preferred. In one embodiment, the gas used to refill the chamber after applying a vacuum is limited to an oxygen content of 98 ppm by volume or less. In one embodiment, the gas used to refill the chamber after applying a vacuum is limited to an oxygen content of 9 ppm by volume or less. In one embodiment, the gas used to refill the chamber after applying a vacuum is limited to an oxygen content of 2 ppm by volume or less. In one embodiment, the gas used to refill the chamber after applying a vacuum is limited to an oxygen content of 0.09 ppm by volume or less. In one embodiment, the gas used to refill the chamber after applying a vacuum is limited to an oxygen content of 0.009 ppm by volume or less. In one embodiment, the gas used to refill the chamber after applying a vacuum is limited to a nitrogen content of 98 ppm by volume or less. In another embodiment, in one embodiment, the gas used to refill the chamber is limited to a nitrogen content of 8 ppm by volume or less. In another embodiment, in one embodiment, the gas used to refill the chamber is limited to a nitrogen content of 4 ppm by volume or less. In another embodiment, the gas used for refilling is limited to a nitrogen content of 0.8 ppm by volume or less.In another embodiment, the gas used for refilling is limited to a nitrogen content of 0.08 ppm by volume or less.In another embodiment, in one embodiment, the gas used for refilling is limited to a nitrogen content of 0.0008 ppm by volume or less. In another embodiment, the above is by weight. In one embodiment, the inventors have found that the protective gas used to refill the chamber is preferably not helium. In one embodiment, at least two rinse cycles are performed, each cycle reaching a prescribed vacuum level and refilling with protective atmosphere. In another embodiment, at least four rinse cycles are performed, each cycle reaching a prescribed vacuum level and refilling with protective atmosphere. In another embodiment, at least eight rinse cycles are performed, each cycle reaching a prescribed vacuum level and refilling with protective atmosphere. In one embodiment, only the last refill uses a protective atmosphere gas with an extremely low oxygen concentration, while the intermediate rinses use a less expensive gas. In one application, the atmosphere in the atomization chamber preferably has a reduced oxygen content. In one embodiment, the oxygen content is less than 16% by volume. In another embodiment, the oxygen content is less than 5.8% by volume. In another embodiment, the oxygen content is less than 3.9% by volume. In another embodiment, the oxygen content is less than 0.9% by volume. In another embodiment, the oxygen content is less than 0.2% by volume. In another embodiment, the oxygen content is by weight. In an embodiment, the oxygen trap is used to purposefully react with oxygen in the spray chamber or melt chamber to further reduce the oxygen content. In an embodiment, the oxygen trap is made of a titanium alloy. In an embodiment, the oxygen trap is made of a magnesium alloy. In an embodiment, the oxygen trap is made of an aluminum alloy. In an embodiment, the oxygen trap is made of a silicon alloy. In an embodiment, the oxygen trap is made of a scandium alloy. In an embodiment, the oxygen trap is made of a zircon alloy. In an embodiment, the oxygen trap is made of a hafnium alloy. In an embodiment, the oxygen trap is made of an alloy that is more reactive with oxygen than silicon according to the Ellingham diagram for the processing conditions. In one embodiment, the oxygen trap comprises an alloy that is more reactive with oxygen than iron according to the Ellingham diagram for the processing conditions.In one embodiment, the oxygen trap is heated to above 120°C. In another embodiment, the oxygen trap is heated to above 320°C. In another embodiment, the oxygen trap is heated to above 420°C. In another embodiment, the oxygen trap is heated to above 520°C. In another embodiment, the oxygen trap is heated to above 720°C. In one embodiment, the oxygen trap is heated to above the sublimation temperature of the oxide of the alloy of the oxygen trap, but at the sublimation temperature of the lower oxide. The inventors have found that in some embodiments, the oxygen content in the chamber has an unexpected effect on the shape of the powder and the deviation from sphericity. In one embodiment, the oxygen content in the atomization chamber is kept below 280 ppm by volume before atomization is initiated. In another embodiment, the oxygen content in the atomization chamber is kept below 280 ppm by volume before atomization is initiated. In another embodiment, the oxygen content in the atomization chamber is kept below 90 ppm by volume before atomization is initiated. In another embodiment, the oxygen content in the spray chamber is maintained below 38 ppm by volume before atomization is started. In another embodiment, the oxygen content in the spray chamber is maintained below 18 ppm by volume before atomization is started. In another embodiment, the oxygen content in the spray chamber is maintained below 8 ppm by volume before atomization is started. In another embodiment, the oxygen content in the spray chamber is maintained below 0.8 ppm by volume before atomization is started. In another embodiment, the oxygen content in the spray chamber is maintained below 0.008 ppm by volume before atomization is started. In another embodiment, the oxygen content is by weight (for example, the oxygen content in the spray chamber is maintained below 280 ppm by weight before atomization is started). In one set of embodiments, the oxygen content measured in ppm by volume in the spray chamber is A1s, as parameter PA2 is defined above. * PA2 and A1i * It has been found that A1s should be maintained between 4.4·10 -5 In another embodiment, A1s is 1.9·10 -5 In another embodiment, A1s is 1.1·10 -5 In another embodiment, A1s is 0.4·10 -5In another embodiment, A1s is 4.4·10 -6 In another embodiment, A1s is 1.4·10 -6 In another embodiment, A1i is 9.2·10 -7 In another embodiment, A1i is 4.2·10 -7 In another embodiment, A1i is 1.2·10 -7 In another embodiment, A1i is 0.2·10 -7 In another embodiment, A1i is 1.2·10 -8 In one embodiment, the nitrogen content in the spray chamber is maintained below 280 ppm by volume before spraying begins. In another embodiment, the nitrogen content in the spray chamber is maintained below 90 ppm by volume before the start of spraying. In another embodiment, the nitrogen content in the spray chamber is maintained below 38 ppm by volume before the start of spraying. In another embodiment, the nitrogen content in the spray chamber is maintained below 18 ppm by volume before the start of spraying. In another embodiment, the nitrogen content in the spray chamber is maintained below 8 ppm by volume before the start of spraying. In another embodiment, the nitrogen content in the spray chamber is maintained below 0.8 ppm by volume before the start of spraying. In another embodiment, the nitrogen content in the spray chamber is maintained below 0.008 ppm by volume before the start of spraying. In another embodiment, the nitrogen content is by weight (for example, the nitrogen content in the spray chamber is maintained below 280 ppm by weight before the start of atomization). In one embodiment, the hydrogen content in the spray chamber is maintained below 0.8 ppm by volume before the start of spraying. In another embodiment, the hydrogen content in the atomizing chamber is maintained below 0.008 ppm by volume before atomization begins. In another embodiment, the hydrogen content is by weight (e.g., the hydrogen content in the atomizing chamber is maintained below 0.8 ppm by weight before atomization begins). The inventors have also found that elements that are easily oxidized, such as some elements such as S and P, affect the powder morphology. In one embodiment, the %Cr content should be kept below 2.9 wt% for some molybdenum alloy steels. In another embodiment, the %Cr content should be kept below 1.9 wt% for some molybdenum alloy steels. In another embodiment, the %Cr content should be kept below 0.9 wt% for some molybdenum alloy steels. In another embodiment, the %Cr content should be kept below 0.09 wt% for some molybdenum alloy steels. In one embodiment, the atmosphere in the chamber is purposefully adjusted to increase the surface tension between the liquid metal and the disk material by at least 55 mN / m relative to the surface tension in air, hi one embodiment, the atmosphere in the chamber is purposefully adjusted to increase the surface tension between the liquid metal and the disk material by at least 110 mN / m relative to the surface tension in air.In one embodiment, the atmosphere in the chamber is purposefully adjusted to increase the surface tension between the liquid metal and the disk material by at least 210 mN / m relative to the surface tension in air, hi one embodiment, the atmosphere in the chamber is purposefully adjusted to increase the surface tension between the liquid metal and the disk material by at least 410 mN / m relative to the surface tension in air.

[0054] As mentioned above, centrifugal atomization using a rotating disk of high melting point alloys has not been pursued for production rates or production batches beyond laboratory batches for experimental purposes due to the expected degradation of the powder morphology. Eventually, some systems may choose to employ powders with significantly degraded morphology. To remedy this problem, some systems employ fluids to directly cool the rotating disk or powder. The coolant often consists of water or another liquid, and in some embodiments, high flow rates of gas are injected into the chamber to cool the powder during production. In some specific applications, the inventors have found that in some embodiments, cooling gas jets, fluids, or cooling curtains can be used. Examples of inert gases that may be used in different applications include nitrogen, helium, argon, neon, xenon, krypton, or any other gas that does not react with the molten composition. In some specific applications, it is preferable to use any cooling fluid other than helium. In some specific applications, it is preferable to use any cooling fluid other than helium. In some specific applications, it is preferable to use any cooling fluid other than argon. In some specific applications, it is preferable to use any cooling fluid other than nitrogen. In some applications, the inventors have found that intensive cooling must be avoided. In one embodiment, the inventors have found that, especially for average particle sizes below 72 microns, the 7.1 * 10 2 We have found that cooling rates of less than 10 °C / s are preferred for some applications, particularly for particles less than 47 microns. 4 It has been found that cooling at rates less than 9.6·10 °C / s is considered acceptable. 4Less than °C / s or 9.4·10 3 Cooling rates below 980°C / s are preferred, and in some applications lower cooling rates may be preferred. In some applications the cooling rates are below 980°C / s, 710°C / s, 93°C / s, or even below 46°C / s. In other, certain applications the inventors have found that it is beneficial to produce powders without the use of gas jets or cooling curtains to cool the powder. For many of the powders considered herein, direct contact with water or water vapor resulting from the interaction of water with hot rotors is very detrimental to the morphological quality of the produced powder, often resulting in powders with excessive oxygen content at the surface. Other liquids tend to affect morphology as well. Also, high gas flow rates tend to generate internal porosity in some powders, and gases acting as a source of oxygen often also act as a source of surface oxidation due to the large amounts required, even when very pure gases are used. In one embodiment, contact of the liquid with the atomizing disk at 0.9 l / s or less is permitted. In another embodiment, the spray disc is allowed to come into contact with the liquid at a rate of not more than 0.9 l / min. In another embodiment, the spray disc is allowed to come into contact with the liquid at a rate of not more than 0.9 l / h. In another embodiment, the spray disc is allowed to come into contact with the liquid at a rate of not more than 0.09 l / h. In one embodiment, it is necessary that no liquid comes into contact with the spray disc during the atomization process. In one embodiment, the amount of liquid in contact with the spray disc refers to the average amount over the entire atomization batch. In an embodiment, what has been said about the liquid in contact with the spray disc also applies to the free liquid in the spray chamber (as opposed to the liquid circulating in a closed circuit). In one embodiment, the liquid consists of water. In one embodiment, the liquid is allowed to come into contact with the spray disc at a rate of not more than 9 m3 of the gas injected into the spray chamber. 3 3. In one embodiment, up to 0.9 m3 / s of gas is allowed to contact the atomized powder after it leaves the disk during the atomization process. 3 3. In one embodiment, less than 0.9 m3 / s of gas is allowed to contact the atomized powder after it leaves the disk during the atomization process. In another embodiment, less than 0.9 m3 / s of gas is injected into the atomization chamber. 33. In one embodiment, up to 0.9 m3 / min of gas is allowed to contact the atomized powder after it leaves the disk during the atomization process. 3 / h of gas is allowed to come into contact with the atomized powder after it leaves the disk during the atomization process. In another embodiment, 0.09 m 3 / h or less of gas is allowed to come into contact with the atomized powder after it leaves the disk during the atomization process. The inventors have surprisingly found that the present invention allows the atomization of fine powders of high morphological quality of highly reactive, very light, low melting alloys, which were previously impossible to atomize. Even more surprisingly, this can be achieved by centrifugal atomization using a rotating body. In one embodiment, high morphological quality means a sphericity of 55% or more. In another embodiment, high morphological quality means a sphericity of 78% or more. In another embodiment, high morphological quality means a sphericity of 86% or more. In another embodiment, high morphological quality means a sphericity of 97% or more. In another embodiment, high morphological quality means a sphericity of 98.2% or more. In another embodiment, high morphological quality means a sphericity of 99.1% or more. The sphericity of a powder refers to a dimensionless parameter defined as the ratio of the surface area of ​​a sphere having the same volume as the particle to the surface area of ​​the particle. The sphericity of the particles is determined by dynamic image analysis. In one embodiment, high morphology quality means a porosity of 38% or less by volume. In another embodiment, high morphology quality means a porosity of 18% or less by volume. In another embodiment, high morphology quality means a porosity of 8% or less by volume. In another embodiment, high morphology quality means a porosity of 0.8% or less by volume. In one embodiment, powder refers to particulate matter with a diameter of 1000 microns or less. In one embodiment, fine refers to a porosity of 0.8% or less by volume. 50 In another embodiment, fine refers to a particle size of 780 microns or less. 50 In another embodiment, fine refers to a particle size of 380 microns or less. 50 In another embodiment, fine refers to a particle size of 180 microns or less. 50 In another embodiment, fine refers to a particle size of 80 microns or less.50 In another embodiment, fine refers to a D 50 In another embodiment, fine refers to a D 50 In another embodiment, fine refers to a D 50 In one embodiment, highly reactive means that the aluminum has a higher affinity for oxygen than aluminum in air at room temperature according to the Ellingham diagram. In one embodiment, highly reactive means that the Y-axis of the Ellingham diagram is cut at -210 Kcal or less. In one embodiment, highly reactive means that the Y-axis of the Ellingham diagram is cut at -230 Kcal or less. In another embodiment, highly reactive means that the Y-axis of the Ellingham diagram is cut at -260 Kcal or less. In one embodiment, very lightweight means that the density at normal conditions is 3.4 g / cm 3 In another embodiment, very light weight means a density of 2.6 g / cm3 or less under normal conditions. 3 In another embodiment, very light weight means a density of 1.8 g / cm3 or less under normal conditions. 3 In another embodiment, very light weight means a density of 1.6 g / cm3 or less under normal conditions. 3 In another embodiment, very light weight means a density of 0.98 g / cm3 or less under normal conditions. 3 In another embodiment, very light weight means a density of 0.68 g / cm3 or less under normal conditions. 3In one embodiment, low melting point alloy refers to an alloy having a melting point of 590°C or less. In another embodiment, low melting point alloy refers to an alloy having a melting point of 490°C or less. In another embodiment, low melting point alloy refers to an alloy having a melting point of 290°C or less. In another embodiment, low melting point alloy refers to an alloy having a melting point of 190°C or less. In another embodiment, low melting point alloy refers to an alloy having a melting point of 140°C or less. In another embodiment, low melting point alloy refers to an alloy having a melting point of 90°C or less. In one embodiment, atomization refers to centrifugal atomization. In one embodiment, atomization refers to centrifugal atomization by a rotating disk. In the inventor's opinion, the present invention provides an atomized powder of lithium alloy of magnesium alone, which has high morphological quality. In one embodiment, the powder produced is a lithium based alloy of magnesium. In one embodiment, %Mg is 3.2wt% or more. In another embodiment, %Mg is 6.2wt% or more. In another embodiment, %Mg is 12wt% or more. In another embodiment, %Mg is 22wt% or more. In another embodiment, %Mg is 36wt% or more. The present invention, in the inventor's view, is the sole invention of an atomized powder of magnesium alloy of lithium, which has high morphological quality. In one embodiment, the powder produced is a magnesium based alloy of lithium. In one embodiment, %Li is 3.2wt% or more. In another embodiment, %Li is 6.2wt% or more. In another embodiment, %Li is 12wt% or more. In another embodiment, %Li is 22wt% or more. In another embodiment, %Li is 36wt% or more. The present invention, in the inventor's view, is the sole invention of an atomized powder of lithium alloy of aluminum, which has high morphological quality. In one embodiment, the powder produced is a lithium based alloy of aluminium. In one embodiment, %Al is 3.2wt% or more. In another embodiment, %Al is 6.2wt% or more. In another embodiment, %Al is 12wt% or more. In another embodiment, %Al is 22wt% or more. In another embodiment, %Al is 36wt% or more. The present invention is, in the inventor's opinion, the sole invention of an atomized powder of lithium based aluminium alloy, having high morphological quality.In one embodiment, the powder produced is an aluminum based alloy comprising lithium. In one embodiment, the %Li is 3.2 wt% or more. In another embodiment, the %Li is 6.2 wt% or more. In another embodiment, the %Li is 12 wt% or more. In another embodiment, the %Li is 22 wt% or more. In another embodiment, the %Li is 36 wt% or more. The present invention provides an atomized powder of molten metal (MM) gallium alloy having high morphological quality. In one embodiment, the powder produced is a molten metal (MM) gallium based alloy. In one embodiment, the %MM is 3.2 wt% or more. In another embodiment, the %MM is 6.2 wt% or more. In another embodiment, the %MM is 12 wt% or more. In another embodiment, the %MM is 22 wt% or more. In another embodiment, the %MM is 36 wt% or more. In one embodiment, the molten metal is aluminum. In one embodiment, the molten metal is titanium. In one embodiment, the molten metal is iron. In one embodiment, the molten metal is nickel. In one embodiment, the molten metal is cobalt. In the inventor's view, the present invention provides an atomized powder of an aluminum alloy of gallium, which is of high morphological quality. In one embodiment, the powder produced is an aluminum-based alloy of gallium. In one embodiment, %Ga is 3.2 wt% or more. In another embodiment, %Ga is 6.2 wt% or more. In another embodiment, %Ga is 12 wt% or more. In another embodiment, %Ga is 22 wt% or more. In another embodiment, %Ga is 36 wt% or more. In the inventor's view, the present invention provides an atomized powder of an aluminum alloy of gallium, which is of high morphological quality. In one embodiment, the powder produced is a titanium based alloy comprised of gallium. In one embodiment, the %Ga is 3.2 wt% or more. In another embodiment, the %Ga is 6.2 wt% or more. In another embodiment, the %Ga is 12 wt% or more. In another embodiment, the %Ga is 22 wt% or more. In another embodiment, the %Ga is 36 wt% or more. In the inventor's opinion, the present invention provides an atomized powder of an iron alloy comprised of gallium, which has high morphological quality. In one embodiment, the powder produced is an iron based alloy comprised of gallium. In one embodiment, the %Ga is 3.2 wt% or more. In another embodiment, the %Ga is 6.2 wt% or more. In another embodiment, the %Ga is 12 wt% or more. In another embodiment, the %Ga is 22 wt% or more. In another embodiment, %Ga is 36wt% or more. In the inventor's opinion, the present invention provides an atomized powder of a nickel alloy of gallium alone, which has high morphological quality. In one embodiment, the powder produced is a nickel-based alloy of gallium. In one embodiment, %Ga is 3.2wt% or more. In another embodiment, %Ga is 6.2wt% or more. In another embodiment, %Ga is 12wt% or more. In another embodiment, %Ga is 22wt% or more. In another embodiment, %Ga is 36wt% or more. In the inventor's opinion, the present invention provides an atomized powder of a cobalt alloy of gallium alone, which has high morphological quality. In one embodiment, the powder produced is a cobalt-based alloy of gallium. In one embodiment, %Ga is 3.2wt% or more. In another embodiment, %Ga is 6.2wt% or more. In another embodiment, %Ga is 12 wt% or more. In another embodiment, %Ga is 22 wt% or more. In another embodiment, %Ga is 36 wt% or more. In this paragraph, for an alloy to be an alloy based on a particular metal, that metal must be the majority component of the alloy. In one embodiment, the component with the largest weight percentage is the majority component.

[0055] In this specification, D50 This refers to the particle size at which 50% of the volume of a sample is made up of smaller particles in the cumulative distribution of particle size distribution. Particle size is measured by laser diffraction method according to ISO 13320-2009.

[0056] In another embodiment, the disclosed D 50 The value of D means the particle size at which 50% of the sample mass is made up of smaller particles in the cumulative particle size distribution. 50 Particle size is measured by laser diffraction according to ISO 13320-2009.

[0057] Any embodiment disclosed herein may be combined with any other embodiment in any combination, provided they are not mutually exclusive. Some combinations of embodiments are as follows: [1] A method for producing a metal-based alloy powder or particulate material by means of centrifugal atomization in a closed chamber, comprising the steps of a) providing a composition of at least one metal, b) melting the composition, and c) atomizing the molten composition by means of centrifugal atomization or rotary atomization. [2] A method for producing a metal-based alloy powder by means of centrifugal atomization in a closed chamber, comprising the steps of a) providing a composition of at least one metal, b) melting the composition, and c) centrifugal atomizing the molten composition. [3] A method according to any of [1] to [2], wherein the atmosphere in the closed atomization chamber is pressurized. [4] A method according to any of [1] to [2], wherein the atmosphere in the closed atomization chamber is cooled. [5] A method according to any of [1] to [2], wherein the atmosphere in the closed atomization chamber is pressurized or cooled. [6] A method according to any of [1] to [5], wherein the atomization chamber comprises an atomization disk. [7] The method according to any of [1] to [6], wherein atomization is performed using a spray disk. [8] The method according to any of [1] to [7], wherein PA2 is greater than 4,500,000. [9] The method according to any of [1] to [7], wherein PA2 is greater than 5,000,000.

[10] The method according to any of [1] to [7], wherein PA2 is greater than 6,000,000.

[11] The method according to any of [1] to [7], wherein PA2 is greater than 7,000,000.

[12] The method according to any of [1] to [7], wherein PA2 is less than 70,000,000.

[13] The method according to any of [1] to [7], wherein PA2 is less than 40,000,000.

[14] The method according to any of [1] to [7], wherein PA2 is less than 30,000,000.

[15] The method according to any of [1] to [7], wherein PA2 is less than 20,000,000.

[16] PA2=K1 * PA1+K2 * P, where P is the absolute pressure in the atomization chamber in Pa, and PA1 = ρ * N 2* d 2 where ρ is kg / m 3where K1 is the density of the composition to be atomized at its melting point under an absolute pressure of 1 bar measured in m, N is the rotational speed of the atomizing disk in rad / s, and d is the diameter of the atomizing disk in m.

[17] The method according to any of [8] to

[16] , where K1 = 0.0033 at 1 / Pa and K2 = 22 at 1 / Pa.

[18] The method according to any of [8] to

[16] , where the composition to be atomized is an aluminum-based alloy, where K1 = 0.01 at 1 / Pa and K2 = 20 at 1 / Pa.

[19] The method according to any of [8] to

[16] , where K1 = 0.015 at 1 / Pa and K2 = 22 at 1 / Pa when the composition to be atomized is a magnesium-based alloy.

[20] The method according to any of [8] to

[16] , where K1 = 0.0033 at 1 / Pa and K2 = 20 at 1 / Pa when the composition to be atomized is an iron-based alloy.

[21] A method according to any of [8] to

[16] , wherein K1 = 0.0033 at 1 / Pa and K2 = 21 at 1 / Pa when the composition being sprayed is a nickel-based alloy.

[22] A method according to any of [8] to

[16] , wherein K1 = 0.0033 at 1 / Pa and K2 = 21 at 1 / Pa when the composition being sprayed is a cobalt-based alloy.

[23] A method according to any of [8] to

[16] , wherein K1 = 0.0033 at 1 / Pa and K2 = 21 at 1 / Pa when the composition being sprayed is a copper-based alloy.

[24] A method according to any of [1] to

[23] , wherein the absolute pressure in the atomization chamber is greater than 1.2 bar.

[25] A method according to any of [1] to

[23] , wherein the absolute pressure in the atomization chamber is greater than 2.6 bar.

[26] A method according to any of [1] to

[23] , wherein the absolute pressure in the atomization chamber is greater than 2.8 bar.

[27] A method according to any of [1] to

[27] , in which the absolute pressure in the spray chamber is less than 999.4 bar.

[28] A method according to any of [1] to

[27] , in which the absolute pressure in the spray chamber is less than 99.2 bar.

[29] A method according to any of [1] to

[27] , in which the absolute pressure in the spray chamber is less than 29.6 bar.

[30] A method according to any of [1] to

[27] , in which the absolute pressure in the spray chamber is less than 19.2 bar.

[31] A method according to any of [1] to

[27] , in which PA3 is less than 10000, PA3 = PA1 / P, and PA1 = ρ * N 2* d 2and ρ is kg / m 3 where N is the rotational speed of the spray disk (rad / s), d is the diameter of the spray disk (m), and P is the pressure in the spray chamber (Pa), according to any of the methods from [1] to

[30] .

[32] PA3 is less than 7000, PA3 = PA1 / P, and PA1 = ρ * N 2* d 2 and ρ is kg / m 3 where N is the rotational speed of the spray disk (rad / s), d is the diameter of the spray disk (m), and P is the pressure in the spray chamber (Pa), according to any of the methods from [1] to

[31] .

[33] PA3 is less than 6000, PA3 = PA1 / P, and PA1 = ρ * N 2* d 2 and ρ is kg / m 3where N is the density of the composition to be sprayed at its melting point under an absolute pressure of 1 bar measured at 100° C., N is the rotation speed of the spray disk (rad / s), d is the diameter of the spray disk (m), and P is the pressure in the spray chamber (Pa).

[34] The method according to any of [1] to

[33] , wherein the compositions to be sprayed are superheated at a temperature equal to or higher than their melting point.

[35] The method according to any of [1] to

[33] , wherein the compositions to be sprayed are superheated at a temperature of at least 52° C. above their melting temperature (Tm).

[36] The method according to any of [1] to

[33] , wherein the compositions to be sprayed are superheated at a temperature of at least 106° C. above their melting temperature (Tm).

[37] The method according to any of [1] to

[36] , wherein the compositions to be sprayed are superheated at a temperature below 396° C.+Tm, Tm being the melting temperature of the composition to be sprayed in degrees Celsius (° C.).

[38] The method according to any of [1] to

[36] , wherein the composition to be sprayed is heated at a temperature below 294°C+Tm, Tm being the melting temperature of the composition to be sprayed in degrees Celsius (°C).

[39] The method according to any of [1] to

[38] , wherein the contact angle between the molten composition and the spray disk is greater than 76°.

[40] The method according to any of [1] to

[38] , wherein the contact angle between the molten composition and the spray disk is greater than 96°.

[41] The method according to any of [1] to

[38] , wherein the contact angle between the molten composition and the spray disk is greater than 106°.

[42] The method according to any of [1] to

[41] , wherein the contact angle between the molten composition and the spray disk is less than 168°.

[43] The method according to any of [1] to

[41] , wherein the contact angle between the molten composition and the spray disk is greater than 158°.

[44] The contact angle between the molten composition and the spray disk is between Cs and Ci, and Cs=185°-0.2 * (T-Tm) and Ci=120°-0.2 *(T-Tm), where T is the temperature of the molten composition being atomized in degrees Celsius (°C) and Tm is the melting temperature of the composition being atomized in degrees Celsius (°C).

[45] The method according to any of

[39] to

[44] , wherein the contact angle is measured according to the Sessile Drop Method.

[46] The method according to any of [1] to

[45] , wherein the surface tension between the molten composition and the surface of the spray disk is greater than 680 mN / m.

[47] The method according to any of [1] to

[45] , wherein the surface tension between the molten composition and the surface of the spray disk is greater than 780 mN / m.

[48] The method according to any of [1] to

[47] , wherein the surface tension between the molten composition and the surface of the spray disk is less than 1750 mN / m.

[49] The method according to any of [1] to

[47] , wherein the surface tension between the molten composition and the surface of the spray disk is less than 1550 mN / m.

[50] The surface tension between the molten composition and the surface of the spray disk, measured in mN / m, is between STs and STi, where STs=1450-0.8 * (T-Tm) and STi=820-0.7 *(T-Tm), where T is the temperature of the molten composition to be atomized in degrees Celsius (°C) and Tm is the melting temperature of the composition to be atomized in degrees Celsius (°C).

[51] The method according to any of

[46] to

[50] , wherein the surface tension is measured according to the Sessile Droplet Method.

[52] The method according to any of [1] to

[51] , wherein the spray disk is made of a material consisting of a ceramic.

[53] The method according to any of [1] to

[51] , wherein the spray disk is ceramic.

[54] The method according to any of [1] to

[51] , wherein the spray disk is made of a material consisting of a titanate.

[55] The method according to any of [1] to

[51] , wherein the spray disk is made of a material consisting of barium titanate.

[56] The method according to any of [1] to

[51] , wherein the spray disk is made of a material consisting of barium titanate in which the barium is at least partially substituted with strontium.

[57] A method according to any one of [1] to

[52] , in which the atomizing disc is made of a material consisting of a metal.

[58] A method according to any one of [1] to

[51] , in which the atomizing disc is metal.

[59] A method according to any one of [1] to

[52] , in which the atomizing disc is made of a material consisting of an intermetallic compound.

[60] A method according to any one of [1] to

[59] , in which the atomizing chamber is constructed integrally with the atomizing disc and the shaft.

[61] A method according to any one of [1] to

[60] , in which the atomizing disc is at least partially coated.

[62] A method according to any one of [1] to

[60] , in which the coating consists of a titanate.

[63] A method according to any one of

[61] to

[62] , in which the coating consists of a titanate.

[64] A method according to any one of

[60] to

[61] , in which the coating consists of barium titanate.

[65] A method according to any one of

[61] to

[62] , in which the coating consists of barium titanate, the barium being at least partially replaced by strontium.

[66] A method according to any of

[61] to

[65] , wherein the coating has a thickness of 2.1 microns or more.

[67] A method according to any of

[61] to

[65] , wherein the coating has a thickness of 72.1 microns or more.

[68] A method according to any of

[61] to

[67] , wherein the coating has a thickness of less than 490 microns.

[69] The method according to any of

[61] to

[67] , wherein the coating has a thickness of less than 160 microns.

[70] The method according to any of

[61] to

[69] , wherein the coating consists of at least two layers.

[71] The method according to

[70] , wherein the layers have different compositions.

[72] The method according to any of

[70] to

[71] , wherein the first coating layer applied on the spray disc is a metallic coating layer.

[73] The method according to any of

[70] to

[71] , wherein the first coating layer applied on the spray disc is a ceramic coating layer.

[74] The method according to any of

[70] to

[71] , wherein the thickness of each coating layer is according to any of

[68] to

[69] .

[75] The method according to any of

[61] to

[74] , wherein the coating is applied by plasma spraying.

[76] The method according to any of [6] to

[75] , wherein the coating is applied by plasma spraying.

[77] The method according to any of [1] to

[76] , wherein the composition of at least one metal provided in step a) is a composition comprising a metal-based alloy. (

[78] The method according to any of [1] to

[76] , wherein the composition of at least one metal provided in step a) is a composition comprising an aluminium-based alloy. (

[79] Any of [1] to

[76] , wherein the composition of at least one metal provided in step a) is a composition comprising an aluminium-based alloy. or according to any one of the preceding claims.

[80] The method according to any one of the preceding claims, [1] to

[76] , wherein the composition of at least one metal provided in step a) is a composition comprising a magnesium-based alloy.

[81] The method according to any one of the preceding claims, [1] to

[76] , wherein the composition of at least one metal provided in step a) is a composition comprising a magnesium-based alloy.

[82] The method according to any one of the preceding claims, [1] to

[76] , wherein the composition of at least one metal provided in step a) is a composition comprising a lithium-based alloy.

[83] The method according to any one of the preceding claims, [1] to

[76] , wherein the composition of at least one metal provided in step a) is a composition comprising a lithium-based alloy.

[84] The method according to any one of the preceding claims, [1] to

[76] , wherein the composition of at least one metal provided in step a) is a composition comprising a copper-based alloy.

[85] The method according to any one of the preceding claims, [1] to

[76] , wherein the composition of at least one metal provided in step a) is a composition comprising a copper-based alloy.

[86] The method according to any of [1] to

[76] , wherein the composition of at least one metal provided in step a) is a composition consisting of a germanium-based alloy.

[87] The method according to any of [1] to

[76] , wherein the composition of at least one metal provided in step a) is a composition consisting of a germanium-based alloy.

[88] The method according to any of [1] to

[76] , wherein the composition of at least one metal provided in step a) is a composition consisting of a silver-based alloy.

[89] The method according to any of [1] to

[76] , wherein the composition of at least one metal provided in step a) is a composition consisting of a silver-based alloy.

[90] The method according to any of [1] to

[76] , wherein the composition of at least one metal provided in step a) is a composition consisting of a gold-based alloy.

[91] The method according to any of [1] to

[76] , wherein the composition of at least one metal provided in step a) is a composition consisting of a gold-based alloy.

[92] The method according to any of

[77] to

[91] , wherein the alloy comprises at least one element selected from the following methods: %Mg, %Si, %Zn with a content of 0.3 wt% or more and 9.8 wt% or less.

[93] A method according to any of

[77] to

[91] , wherein the alloy comprises at least two elements selected from among the methods in which the %Mg, %Si, %Zn contents are ≧0.3wt% and ≦9.8wt%.

[94] A method according to any of

[77] to

[93] , wherein the alloy comprises at least one element selected from the methods in which the %Sc, %Zr, %Cu, %Mn and %Fe contents are ≧0.002wt% and ≦5.9wt%.

[95] A method according to any of

[77] to

[93] , wherein the alloy comprises at least two elements selected from the methods in which the %Sc, %Zr, %Cu, %Mn and %Fe contents are ≧0.002wt% and ≦5.9wt%.

[96] A method according to any of

[77] to

[93] , wherein the alloy consists of at least three elements selected from %Sc, %Zr, %Cu, %Mn and %Fe with contents between 0.002wt% and 5.9wt%.

[97] A method according to any of

[77] to

[96] , wherein the alloy contains %K, %P or %Cr less than 94ppm by weight.

[98] A method according to any of

[77] to

[97] , wherein the alloy contains %Sb or %Li less than 0.8ppm by weight.

[99] A method according to any of

[77] to

[98] , wherein the alloy contains Na, Ga or Ca less than 590ppm by weight.

[0100] A method according to any of

[77] to

[99] , wherein the alloy comprises %Sr less than 1.9wt%.

[0101] A method according to any of [1] to

[38] , wherein the contact angle between the molten composition and the spray disc is greater than 76°.

[0102] The method according to any one of [1] to

[38] , wherein the contact angle between the molten composition and the spray disc is greater than 98°.

[0103] The method according to any one of [1] to

[38] , and

[0101] to

[0103] , wherein the contact angle between the molten composition and the spray disc is greater than 106°.

[0104] The method according to any one of [1] to

[38] and

[0101] to

[0103] , wherein the contact angle between the molten composition and the spray disc is less than 172°.

[0105] The method according to any one of [1] to

[38] and

[0101] to

[0103] , wherein the contact angle between the molten composition and the spray disc is less than 156°.

[0106] The contact angle between the molten composition and the spray disc is between Cs and Ci, and Cs=185°-0.2. * (T-Tm) and Ci=120-0.2 *(T-Tm), where T is the temperature of the molten composition being sprayed in degrees Celsius (°C) and Tm is the melting temperature of the composition being sprayed in degrees Celsius (°C).

[0107] The method according to any of

[0101] to

[0106] , wherein the contact angle is measured according to the Sessile Drop Method.

[0108] The method according to any of [1] to

[38] and

[0101] to

[0107] , wherein the surface tension between the molten composition and the surface of the spray disc is greater than 810 mN / m.

[0109] The method according to any of [1] to

[38] and

[0101] to

[0107] , wherein the surface tension between the molten composition and the surface of the spray disc is greater than 910 mN / m.

[0110] The method according to any one of [1] to

[38] and

[0101] to

[0109] , wherein the surface tension between the molten composition and the surface of the spray disk is less than 2190 mN / m.

[0111] The method according to any one of [1] to

[38] and

[0101] to

[0109] , wherein the surface tension between the molten composition and the surface of the spray disk is less than 1990 mN / m.

[112] The surface tension between the molten composition and the surface of the spray disk, measured in mN / m, is between STs and STi, and STs=1700-0.8 * (T-Tm) and STi=1100-0.9 *(T-Tm), where T is the temperature of the molten composition being atomized in degrees Celsius (°C) and Tm is the melting temperature of the composition being atomized in degrees Celsius (°C).

[0113] The method according to any of

[0108] to

[0112] , wherein the surface tension is measured according to the Sessile Drop Method.

[0114] The method according to any of [1] to

[38] and

[0101] to

[0113] , wherein the spray disk is made of a material consisting of alumina (Al2O3).

[0115] The method according to any of [1] to

[38] and

[0101] to

[0113] , wherein the spray disk is made of alumina (Al2O3).

[0116] The method according to any of [1] to

[38] and

[0101] to

[0113] , wherein the spray disk is made of a material consisting of aluminium nitride (AlN).

[0117] A method according to any one of [1] to

[38] and

[0101] to

[0113] , wherein the spray disc is made of aluminum nitride (AlN).

[0118] A method according to any one of [1] to

[38] and

[0101] to

[0113] , wherein the spray disc is made of a material consisting of a stable oxide.

[0119] A method according to any one of [1] to

[38] and

[0101] to

[0113] , wherein the spray disc is made of a material consisting of magnesium oxide (MgO).

[0120] A method according to any one of [1] to

[38] and

[0101] to

[0113] , wherein the metal part of the spray disc is made of a material consisting of an oxide operating in an oxidation state of III or higher.

[0121] A method according to any one of [1] to

[38] and

[0101] to

[0113] , wherein the metal part of the spray disc is made of a material containing, as a majority, an oxide operating in an oxidation state of III or higher.

[0122] A method according to any one of [1] to

[38] and

[0101] to

[0113] , wherein the metal part of the spray disc is made of a material consisting of an oxide which operates in an oxidation state of IV or higher.

[0123] A method according to any one of [1] to

[38] and

[0101] to

[0113] , wherein the metal part of the spray disc is made of a material which contains in large part an oxide which operates in an oxidation state of IV or higher.

[0124] A method according to any one of [1] to

[38] and

[0101] to

[0113] , wherein the spray disc is made of a material consisting of titanium oxide.

[0125] The method according to any of [1] to

[38] and

[0101] to

[0113] , wherein the spray disc consists of titanium oxide.

[0126] The method according to any of

[0124] to

[0125] , wherein the predominant phase identified as titanium oxide with %Ti greater than 50 wt% has an oxygen content greater than 26 wt%.

[0127] The method according to any of

[0124] to

[0125] , wherein the predominant phase identified as titanium oxide with %Ti greater than 50 wt% has an oxygen content less than 39 wt%.

[0128] The method according to any of [1] to

[38] and

[0101] to

[0113] , wherein the spray disc is made of a material consisting of TiN and the nitrogen content of the sprayed molten composition is less than 1500 ppm by weight.

[0129] The method according to any one of [1] to

[38] and

[0101] to

[0113] , wherein the atomizing disc is TiN and the nitrogen content of the molten composition to be sprayed is less than 1500 ppm by weight.

[0130] The method according to any one of [1] to

[38] and

[0101] to

[0113] , wherein the atomizing disc is made of a material consisting of a metal.

[0131] The method according to any one of [1] to

[38] and

[0101] to

[0113] , wherein the atomizing disc is made of a material consisting of an intermetallic compound.

[0132] The method according to any one of [1] to

[38] and

[0101] to

[0113] , wherein the atomizing chamber is constructed by integrating the atomizing disc and the shaft.

[0133] The method according to any one of [1] to

[38] and

[0101] to

[0132] .

[0134] The method according to any of [1] to

[38] and

[0101] to

[0133] , wherein the spray disc is at least partially coated.

[0135] The method according to any of [1] to

[38] and

[0101] to

[0133] , wherein the spray disc is coated.

[0136] The coating is preferably made of alumina (Al. 2 O 3 The method according to any one of

[0134] to

[0135] , wherein the coating is made of alumina (Al 2 O 3A method according to any one of

[0134] to

[0135] , wherein the coating consists of aluminum nitride (AlN).

[0138] A method according to any one of

[0134] to

[0135] , wherein the coating consists of aluminum nitride (AlN).

[0139] A method according to any one of

[0134] to

[0135] , wherein the coating consists of a stable oxide.

[0141] A method according to any one of

[0134] to

[0135] , wherein the coating consists of magnesium oxide (MgO).

[0142] A method according to any one of

[0134] to

[0135] , wherein the metallic part of the coating consists of an oxide operating in an oxidation state III or higher.

[0143] A method according to any one of

[0134] to

[0135] , wherein the metallic part of the coating comprises in the majority an oxide operating in an oxidation state III or higher.

[0144] A method according to any of

[0134] to

[0135] , wherein the metallic part of the coating consists of an oxide operating in an oxidation state of IV or higher.

[0145] A method according to any of

[0134] to

[0135] , wherein the metallic part of the coating comprises in the main an oxide operating in an oxidation state of IV or higher.

[0146] A method according to any of

[0134] to

[0135] , wherein the coating consists of titanium oxide.

[0147] A method according to any of

[0134] to

[0135] , wherein the coating is made of titanium oxide.

[0148] A method according to any of

[0146] to

[0147] , wherein the predominant phase of titanium oxide with %Ti above 50wt% has an oxygen content above 26wt%.

[0149] A method according to any of

[0146] to

[0147] , wherein the predominant phase of titanium oxide with %Ti above 50wt% has an oxygen content below 39wt%.

[0150] The method according to any one of

[0134] to

[0135] , wherein the coating consists of TiN and the nitrogen content of the molten composition sprayed is less than 1500 ppm by weight.

[0151] The method according to any one of

[0134] to

[0135] , wherein the coating consists of TiN and the nitrogen content of the molten composition sprayed is less than 1500 ppm by weight. A method according to any one of

[0134] to

[0135] , wherein the coating comprises a metal.

[0153] A method according to any one of

[0134] to

[0135] , wherein the coating is a metal.

[0154] A method according to any one of

[0134] to

[0135] , wherein the coating comprises an intermetallic compound.

[0155] A method according to any one of

[0134] to

[0154] , wherein the coating has a thickness of 2.1 microns or more.

[0156] A method according to any one of

[0134] to

[0154] , wherein the coating has a thickness of 72.1 microns or more.

[0157] A method according to any one of

[0134] to

[0156] , wherein the coating has a thickness of less than 490 microns.

[0158] A method according to any one of

[0134] to

[0156] , wherein the coating has a thickness of less than 160 microns.

[0159] A method according to any of

[0134] to

[0158] , wherein the coating consists of at least two layers.

[0160] A method according to

[0159] , wherein the layers have different compositions.

[0161] A method according to any of

[0159] to

[0160] , wherein the first coating layer applied on the spray disc is a metallic coating layer.

[0162] A method according to any of

[0159] to

[0160] , wherein the first coating layer applied on the spray disc is a ceramic coating layer.

[0163] A method according to any of

[0159] to

[0162] , according to any of

[0157] to

[0158] in the thickness of each layer.

[0164] A method according to any of

[0134] to

[0163] , wherein the coating is applied by plasma spraying.

[0165] A method according to any of

[0101] to

[0164] , wherein the spray disc is supported via a cage structure.

[0166] The method according to any of [1] to

[0165] , wherein the composition of at least one metal provided in step a) is a composition consisting of a metal-based alloy.

[0167] The method according to any of [1] to

[38] and

[0101] to

[0165] , wherein the composition of at least one metal provided in step a) is a composition consisting of an iron-based alloy.

[0168] The method according to any of [1] to

[38] and

[0101] to

[0165] , wherein the composition of at least one metal provided in step a) is a composition consisting of an iron-based alloy.

[0169] The method according to any of [1] to

[38] and

[0101] to

[0165] , wherein the composition of at least one metal provided in step a) is a composition consisting of a magnesium based alloy.

[0170] The method according to any of [1] to

[38] and

[0101] to

[0165] , wherein the composition of at least one metal provided in step a) is a magnesium based alloy.

[0171] The method according to any of [1] to

[38] and

[0101] to

[0165] , wherein the composition of at least one metal provided in step a) is a composition consisting of a lithium based alloy.

[0172] The method according to any of [1] to

[38] and

[0101] to

[0165] , wherein the composition of at least one metal provided in step a) is a lithium based alloy.

[0173] The method according to any of [1] to

[38] and

[0101] to

[0165] , wherein the composition of at least one metal provided in step a) is a composition consisting of a copper-based alloy.

[0174] The method according to any of [1] to

[38] and

[0101] to

[0165] , wherein the composition of at least one metal provided in step a) is a copper-based alloy.

[0175] The method according to any of [1] to

[38] and

[0101] to

[0165] , wherein the composition of at least one metal provided in step a) is a composition consisting of a nickel-based alloy.

[0176] The method according to any of [1] to

[38] and

[0101] to

[0165] , wherein the composition of at least one metal provided in step a) is a nickel-based alloy.

[0177] The method according to any of [1] to

[38] and

[0101] to

[0165] , wherein the composition of at least one metal provided in step a) is a composition consisting of a cobalt-based alloy.

[0178] The method according to any of [1] to

[38] and

[0101] to

[0165] , wherein the composition of at least one metal provided in step a) is a cobalt-based alloy.

[0179] The method according to any of [1] to

[38] and

[0101] to

[0165] , wherein the composition of at least one metal provided in step a) is a composition consisting of a titanium-based alloy.

[0180] The method according to any of [1] to

[38] and

[0101] to

[0165] , wherein the composition consisting of at least one metal provided in step a) is a titanium-based alloy.

[0181] The method according to any of

[0101] to

[0180] , wherein the alloy contains %S at least 25 ppm by weight.

[0182] The method according to any of

[0101] to

[0181] , wherein the alloy contains %S less than 400 ppm by weight.

[0183] The method according to any of

[0101] to

[0182] , wherein the alloy contains %P at least 55 ppm by weight.

[0184] The method according to any of

[0101] to

[0183] , wherein the alloy contains %P less than 400 ppm by weight.

[0185] The method according to any of

[0101] to

[0184] , wherein the alloy contains %B at least 6 ppm by weight.

[186] A method according to any of

[0101] to

[0183] , wherein the alloy contains %B less than 400ppm by weight.

[0187] A method according to any of

[0101] to

[0186] , wherein the alloy contains %C less than 4.9wt%.

[0188] A method according to any of

[0101] to

[0187] , wherein the alloy contains the sum of %Mo+%Cr+%W+%V+%Si+%Mn greater than 10.5wt%.

[0189] A method according to any of

[0101] to

[0188] , wherein the alloy has the composition %Cr+%Ta+%Hf greater than 10wt% and %C less than 1.9wt%.

[0190] A method according to any of

[0101] to

[0189] , wherein the alloy contains %Si less than 6.29wt%.

[0191] A method according to any of

[0101] to

[0190] , wherein the alloy contains %Al not more than 0.09wt%.

[0192] A method according to any of

[0101] to

[0191] , wherein the alloy contains %Ti not more than 0.09wt%.

[0193] A method according to any of

[0101] to

[0192] , wherein the alloy contains %Ti of at least 0.0012wt.

[0194] A method according to any of [1] to

[0193] , wherein the oxygen content in the sprayed molten composition is not more than 790ppm by weight.

[0195] A method according to any of [1] to

[0193] , wherein the oxygen content in the sprayed molten composition is not more than 180ppm by weight.

[0196] A method according to any of [1] to

[0195] , wherein there is no direct contact of the molten composition with the liquid.

[0197] The method according to any of [1] to

[0195] , wherein there is no direct contact of the molten composition with any liquid-containing substance.

[0198] The method according to any of [1] to

[0195] , wherein there is no direct contact of the molten composition with water.

[0199] The method according to any of [1] to

[0195] , wherein there is no direct contact of the molten composition with an aqueous fluid.

[0200] The method according to any of [1] to

[0199] , wherein there is no direct contact of the produced powder with a liquid.

[0201] The method according to any of [1] to

[0199] , wherein there is no direct contact of the produced powder with a liquid-containing substance.

[0202] The method according to any of [1] to

[0199] , wherein there is no direct contact of the produced powder with water.

[0203] The method according to any of [1] to

[0199] , wherein there is no direct contact of the produced powder with an aqueous fluid.

[0204] The method according to any of [1] to

[0203] , wherein there is no contact of the molten composition with a cooling gas.

[0205] The method according to any one of [1] to

[0195] , wherein the spray disc is cooled.

[0206] The method according to any one of [1] to

[0195] , wherein the spray chamber consists of a cooled gas curtain.

[0207] The method according to any one of [1] to

[0195] , wherein a circulating gas is introduced into the spray chamber during the atomization step.

[0208] The method according to

[0207] , wherein the circulating gas is an inert gas.

[0209] The flow rate of the circulating gas is 990 m 3

[0210] The method according to any one of

[0207] to

[0208] , wherein the flow rate of the circulating gas is less than 98 m 3

[0211] A method according to any one of

[0207] to

[0208] , wherein the circulation gas is a cooling gas.

[0212] A method according to any one of

[0207] to

[0211] , wherein the circulation gas is a protective gas.

[0213] A method according to

[0212] , wherein the protective gas is cooled by contact with a cold wall.

[0214] A method according to

[0212] , wherein the protective gas is cooled by contact with a heat exchanger.

[0215] A method according to any one of [1] to

[0214] , wherein at least a portion of the gas in the chamber is forced into contact with a cooling element.

[0216] A method according to

[0215] , wherein the portion of the gas in the chamber that is forced into contact with the cooling element reduces its temperature by at least 2°C.

[0217] A method according to

[0218] , wherein the portion of the gas in the chamber that is forced into contact with the cooling element is cooled by at least 1.2 m3 / min. The method according to any of

[0215] to

[0216] , wherein the cooling element is forced into contact with the cooling element.

[0218] The method according to any of [1] to

[0195] , wherein a gas is introduced into the spraying chamber during the spraying step.

[0219] The method according to any of

[0218] to

[0219] , wherein the gas is a cooling gas.

[0220] The method according to any of

[0204] to

[0219] , wherein the cooling gas is an inert gas.

[0221] The method according to

[0220] , wherein the inert gas is helium.

[0222] The method according to

[0220] , wherein the inert gas is argon.

[0223] The method according to

[0220] , wherein the inert gas is nitrogen.

[0224] The method according to

[0220] , wherein the inert gas is xenon.

[0225] The method according to

[0220] , wherein the inert gas is krypton.

[0226] The method according to

[0220] , wherein the inert gas is a gas that does not react with the molten composition being sprayed.

[0227] The method according to

[0220] , wherein the inert gas is a mixture of two or more inert gases.

[0228] The method according to

[0220] , wherein the inert gas is a mixture of at least two gases.

[0229] The method according to any of [1] to

[0228] , wherein the gas is introduced to locally cool an element of the spray disc.

[0230] The method according to any of

[0207] to

[0229] , wherein the gas consists of a mist containing a liquid.

[0231] The method according to

[0230] , wherein the mist consists of a lubricating fluid or particles.

[0232] The method according to

[0231] , wherein the lubricating fluid is an oil.

[0233] The method according to any of

[0207] to

[0232] , wherein the gas cools the bearings of the spray disc.

[0234] A method according to any one of

[0207] to

[0233] , wherein the gas cools the bearings of the spray disk.

[0235] A method according to any one of

[0207] to

[0234] , wherein the gas cools the spray disk.

[0236] A method according to any one of

[0207] to

[0234] , wherein the gas introduced is 0.12 m 3 A method according to any one of

[0207] to

[0235] , in which the gas introduced is 98 m 3 / min or less.

[0238] The method according to any of [1] to

[0237] , wherein the spray disc is externally cooled.

[0239] The method according to any of [1] to

[0238] , wherein the radial stress of the spray disc due to centrifugal force is less than 290 MPa.

[0240] The method according to any of [1] to

[0239] , wherein the radial stress of the spray disc due to centrifugal force is 14 MPa or more.

[0241] The method according to any of

[76] to

[0240] , wherein the cage is made of a metallic material.

[0242] The method according to any of

[76] to

[0240] , wherein the cage is of metallic construction.

[0243] The method according to any of

[76] to

[0242] , wherein the material of the cage has an elongation at break of 0.8% or more at the processing temperature.

[0244] The method according to

[0243] , wherein the elongation at break at the processing temperature is measured according to ASTM E21-17.

[0245] The method according to any of

[0241] to

[0244] , wherein the spray disk is ceramic.

[0246] The stress in the ceramic spray disk at the ceramic spray disk / metal structure interface is measured according to the LFC * σ creep Less than and LSC * σ creep A method according to

[0245] , where the LFC is 1. A method according to

[0246] , where the LSC is 0.7. A method according to

[0249] , where σ is maintained at 0.7. creep The method according to any one of

[0246] to

[0248] , wherein σ is the creep resistance of the metallic material for 10 hours at a fixed working temperature. creep The method according to any one of

[0246] to

[0248] , wherein σ is the creep resistance of the metallic material at 800°C for 10 hours. creep The method according to any one of

[0241] to

[0250] , wherein the σ of the metal material is 12 MPa or more. creep is measured in accordance with ASTM E139-11(2018), according to any of the methods described below. creepThe method according to any one of

[0246] to

[0251] , in which the stress in the ceramic spray disk at the ceramic spray disk / metal structure interface is determined by finite element simulation (FEM).

[0255] The method according to any one of

[0246] to

[0252] , in which the stress in the ceramic spray disk at the ceramic spray disk / metal structure interface is determined by finite element simulation (FEM). 0 +(a ceramic -a metal ) * (T work -295) * (E ceramic +E metal ) / 2], where e 0 is the initial interference due to the tolerance of / 1, and a ceramic is from room temperature to T work is the average thermal expansion coefficient of ceramics up to T work is the steady-state regime processing temperature in Kelvin, and E ceramic is from room temperature to T work is the average elastic modulus up to metal is from room temperature to T work The method according to any one of

[0246] to

[0253] , wherein the elastic modulus of a ceramic is measured at room temperature according to ASTM C1161-18. The method according to

[0255] , wherein the elastic modulus of a ceramic is measured at room temperature according to ASTM C1211-18. workThe method according to

[0255] , wherein the thermal expansion coefficient is measured according to ASTM E831-14. The method according to any of

[0244] and

[0251] , wherein the processing temperature is the temperature of the molten composition. The method according to any of

[0244] and

[0251] , wherein the processing temperature is the temperature of the spray disk. The method according to any of [1] to

[0260] , wherein the temperature of the spray disk is the measured temperature. The method according to any of

[76] to

[0260] , wherein the temperature of the spray disk is calculated using finite element simulation (FEM). The method according to any of [1] to

[0260] , wherein the temperature of the spray disk is Tm-25(°C), where Tm is the melting temperature of the composition being atomized.

[0264] The method according to any one of [1] to

[0260] , wherein the temperature of the spray disk is Tm+40 (°C), Tm being the melting temperature of the composition being atomized. work ) is the temperature of the molten composition being sprayed, where T work ) is the temperature of the molten composition being sprayed in degrees Celsius (°C). workThe method according to any one of

[0249] to

[0258] , wherein the stationary processing temperature (Twork) is Tm-25(°C), where Tm is the melting temperature of the composition being sprayed.

[0267] The method according to any one of

[0249] to

[0258] , wherein the stationary processing temperature (Twork) is Tm+40(°C), where Tm is the melting temperature of the composition being sprayed.

[0268] The method according to any one of

[0249] to

[0258] , wherein the stationary processing temperature is determined by finite element simulation (FEM).

[0269] The method according to any one of [1] to

[0268] , wherein the molten composition being sprayed has a solid phase part.

[0270] The method according to

[0269] , wherein the solid fraction is less than 39 wt%.

[0271] The method according to any one of

[0269] to

[0270] , wherein the solid fraction is more than 0.01 wt%.

[0272] The method according to any one of [1] to

[0271] , wherein the spray disc is flat.

[0273] The method according to any one of [1] to

[0271] , wherein the spray disc is cup-shaped.

[0274] The method according to any one of [1] to

[0271] , wherein the spray disc is cone-shaped.

[0275] The method according to any one of [1] to

[0271] , wherein the spray disc is an integrally formed bulk disc.

[0276] The method according to any one of [1] to

[0275] , wherein the diameter of the spray disc is 36mm or more.

[0277] The method according to any one of [1] to

[0275] , wherein the diameter of the spray disc is 56mm or more.

[0278] The method according to any one of [1] to

[0277] , wherein the diameter of the spray disc is less than 690mm.

[0279] The method according to any one of [1] to

[0277] , wherein the diameter of the spray disc is less than 490mm.

[0280] A method according to any one of [1] to

[0279] , wherein the spray disc comprises protrusions.

[0281] A method according to any one of [1] to

[0279] , wherein at least some of the protrusions are axially asymmetric.

[0282] A method according to any one of [1] to

[0279] , wherein the spray disc comprises radially distributed protrusions.

[0283] A method according to

[0282] , wherein the protrusions have a single curvature.

[0284] A method according to

[0282] , wherein the protrusions have a double curvature.

[0285] A method according to

[0282] , wherein the protrusions are radially linear protrusions.

[0286] A method according to

[0282] , wherein the protrusions are curved backwards.

[0287] A method according to

[0282] , wherein the protrusions are radially curved.

[0288] The method according to

[0282] , wherein the projections are curved forward.

[0289] The method according to any of

[0282] to

[0288] , wherein the number of projections is 2.

[0290] The method according to any of

[0280] to

[0289] , wherein the projections are vanes.

[0291] The method according to any of [1] to

[0290] , wherein the produced batch is a large production batch of 6 kg or more.

[0292] The method according to any of [1] to

[0290] , wherein the produced batch is a very large production batch of 2100 kg or more.

[0293] The method according to any of [1] to

[0292] , wherein the batch productivity is a large batch productivity of 32 kg / h or more.

[0294] The method according to any of [1] to

[0293] , wherein the batch productivity is a large batch productivity of 19400 kg / h or less.

[0295] The method according to any of [1] to

[0294] , wherein the surface of the spray disk is modified to change the wetting behavior of the molten composition on the spray disk.

[0296] The method according to any of [1] to

[0295] , wherein the surface of the spray disk is modified to enhance wettability.

[0297] The method according to any of [1] to

[0295] , wherein the surface of the spray disk is modified such that the contact angle between the molten composition and the modified surface of the spray disk is less than 89°.

[0298] The method according to any of [1] to

[0295] , wherein the surface of the spray disk is modified such that the contact angle between the molten composition and the modified surface of the spray disk is 95°.

[0299] The method according to any of [1] to

[0295] , wherein the surface of the spray disk is modified such that the contact angle hysteresis between the molten composition and the modified surface of the spray disk is less than 25°.

[0300] The method according to

[0296] , wherein the wettability is quantified by the contact angle between the liquid and the solid surface.

[0301] A method according to any of

[0295] to

[0299] , wherein the modification of the atomization disc consists of engraving a pattern.

[0302] A method according to any of

[0295] to

[0299] , wherein the modification of the surface of the spray disc consists of engraving a pattern.

[0303] A method according to any of

[0295] to

[0299] , wherein the modification of the surface of the spray disc consists of engraving with a random pattern.

[0304] A method according to any of

[0295] to

[0299] , wherein the modification of the surface of the spray disc is effected by engraving with a random pattern.

[0305] The method according to any of

[0295] to

[0299] , wherein modifying the surface of the spray disc comprises providing a texture to the surface of the spray disc.

[0306] The method according to

[0305] , wherein the texture is provided by etching.

[0307] The method according to

[0305] , wherein the texture is provided by application of a coating.

[0308] The method according to

[0305] , wherein the texture is provided by a laser light source.

[0309] The method according to

[0305] , wherein the texture is provided via an electron beam source.

[0310] The method according to

[0305] , wherein the texture is provided by laser engraving.

[0311] The method according to any of

[0305] to

[0310] , wherein the pitch of the texture pattern is 9 mm or less.

[0312] The method according to any of

[0305] to

[0310] , wherein the pitch of the texture pattern is 190 microns or less.

[0313] The method according to any of

[0311] to

[0312] , wherein the pitch of the texture patterns is the minimum distance between two adjacent topological relative extremes of the same sign.

[0314] The method according to any of [1] to

[0313] , wherein the spray chamber consists of at least one bearing.

[0315] The method of [1] to

[0313] , wherein the spray chamber consists of a bearing.

[0316] The method of [1] to

[0315] , wherein the spray chamber constitutes a shaft.

[0317] The method according to

[0316] , wherein the distance of the bearing to the spray disk is 990 mm or less.

[0318] The method according to any of

[0315] to

[0317] , wherein the bearing is at least one bearing.

[0319] The method according to any of

[0315] to

[0317] , wherein the bearing is all the bearings on the shaft.

[0320] A method according to any one of

[0315] to

[0317] , wherein the bearings are the two bearings on the shaft closest to the spray disc.

[0321] A method according to any one of

[0315] to

[0317] , wherein the bearings are the bearings on the shaft closest to the spray disc.

[0322] A method according to any one of

[0315] to

[0321] , wherein the bearings have an angular contact of 12°.

[0323] A method according to any one of

[0315] to

[0321] , wherein the bearings have angular contact of 15.5° or more.

[0324] A method according to any one of

[0315] to

[0323] , wherein the bearings have angular contact of 34° or less.

[0325] The method according to any one of

[0315] to

[0323] , wherein the bearing has angular contact of 29° or less.

[0326] The method according to any one of

[0315] to

[0325] , wherein the bearing has progressive angular contact.

[0327] The method according to any one of

[0315] to

[0325] , wherein the bearing has progressive angular contact with a reduction in the space between the outer diameter and the inner diameter of the ring.

[0328] The method according to any one of

[0315] to

[0327] , wherein the bearing has a space between the outer ring and the inner ring of 0.06 mm or more.

[0329] The method according to any one of

[0315] to

[0328] , wherein the bearing has a relative radial displacement between the outer ring and the inner ring.

[0330] The method according to any one of

[0315] to

[0329] , wherein the bearing has a relative radial displacement between the outer ring and the inner ring of 2.1 mm or more.

[0331] The method according to any one of

[0315] to

[0330] , wherein the bearing constitutes a cylinder as a rotating body.

[0332] The method according to any one of

[0315] to

[0331] , wherein the bearing constitutes a ball as a rotating body.

[0333] The method according to any one of

[0315] to

[0332] , wherein the bearing comprises a ceramic rotating body.

[0334] The method according to any one of

[0315] to

[0332] , wherein the bearing comprises a metal ring with high temperature performance.

[0335] The method according to any one of

[0315] to

[0332] , wherein the bearing comprises a metal outer ring with high temperature performance.

[0336] The method according to any one of

[0315] to

[0332] , wherein the high temperature performance metal material is a material having high hardness after long-term exposure to high temperature.

[0337] The method according to

[0336] , wherein the high hardness is 54HRc or more.

[0338] The method according to any one of

[0336] to

[0337] , wherein the hardness is measured at room temperature according to ASTM E18-18a.

[0339] The method according to any one of

[0336] to

[0337] , wherein the hardness is measured at a processing temperature according to ASTM E18-18a.

[0340] The method according to

[0339] , wherein the long exposure is 35 minutes or more.

[0341] The method according to

[0339] , wherein the elevated temperature is 85°C or more.

[0342] The method according to any one of

[0315] to

[0341] , wherein the bearing comprises a high temperature exposure resistant lubricant.

[0343] The bearing has a high maximum processing temperature. A method according to any one of

[0315] to

[0341] , wherein the lubricant comprises a lubricant.

[0344] A method according to

[0343] , wherein the maximum processing temperature is equal to or greater than 86°C.

[0345] A method according to any one of

[0315] to

[0344] , wherein the lubricant is applied to the bearing.

[0346] A method according to any one of

[0315] to

[0344] , wherein the lubricant is continuously applied to the bearing.

[0347] A method according to any one of

[0345] to

[0346] , wherein the application of the lubricant consists of pulses of application, and time passes without application of new lubricant.

[0348] A method according to any one of

[0315] to

[0347] , wherein the outer ring of the bearing is flexible.

[0349] A method according to any one of

[0315] to

[0348] , wherein the inner ring of the bearing is outside the processing tolerances at room temperature, but within the processing tolerances at the processing temperature.

[0350] A method according to any one of

[0315] to

[0349] , in which the shaft connecting the bearing and the spray disk is made of a low thermal conductivity material.

[0351] A method according to

[0350] , in which the low thermal conductivity material is made of a metal or metal alloy.

[0352] A method according to

[0350] , in which the low thermal conductivity is 90 W / mK or less.

[0353] A method according to any one of

[0350] to

[0352] , in which the thermal conductivity is measured at room temperature in accordance with ASTM E1461-13.

[0354] A method according to any one of

[0350] to

[0352] , in which the thermal conductivity is measured at standard processing temperatures in accordance with ASTM E1461-13.

[0355] A method according to any one of

[0315] to

[0354] , in which cooling is applied around the bearing.

[0356] The method according to any of

[0315] to

[0354] , wherein cooling is applied directly to the shaft on which the bearing is mounted.

[0357] The method according to any of

[0315] to

[0354] , wherein cooling is applied directly to a component of the bearing.

[0358] The method according to any of

[0355] to

[0357] , wherein the cooling medium consists of a phase that changes on contact with the surface to be cooled, such phase change consisting of evaporation or sublimation.

[0359] The method according to any of [1] to

[0358] , wherein the powder produced has an oxygen content of 490 ppm by weight or less.

[0360] The method according to any of [1] to

[0359] , wherein the powder produced has a nitrogen content of 490 ppm by weight or less.

[0361] The method according to any of [1] to

[17] , wherein the powder produced is an iron powder.

[0362] The method according to any one of [1] to

[17] , wherein the produced powder is a powder of an alloy consisting of iron.

[0363] The method according to any one of [1] to

[17] , wherein the produced powder is a powder of an alloy consisting mostly of iron.

[0364] The method according to any one of [1] to

[17] , wherein the produced powder is an iron-based alloy powder.

[0365] The method according to any one of [1] to

[17] , wherein the produced powder is a tool steel powder.

[0366] The method according to any one of [1] to

[17] , wherein the produced powder is a hot work tool steel powder.

[0367] The method according to any one of [1] to

[17] , wherein the produced powder is a titanium-based alloy powder.

[0368] The method according to any one of [1] to

[17] , wherein the produced powder is a powder of an alloy consisting mostly of titanium.

[0369] The method according to any one of [1] to

[17] , wherein the produced powder is a powder of an alloy consisting mostly of titanium.

[0370] The method according to any one of [1] to

[17] and

[21] , wherein the produced powder is a nickel-based alloy powder.

[0371] The method according to any one of [1] to

[17] and

[21] , wherein the produced powder is a powder of an alloy consisting of nickel.

[0372] The method according to any one of [1] to

[17] and

[21] , wherein the produced powder is a powder of an alloy consisting of nickel as a majority component.

[0373] The method according to any one of [1] to

[18] , wherein the produced powder is an aluminium-based alloy powder.

[0374] The method according to any one of [1] to

[18] , wherein the produced powder is a powder of an alloy consisting of aluminium.

[0375] The method according to any one of [1] to

[18] , wherein the produced powder is a powder of an alloy consisting of aluminium as a majority component.

[0376] The method according to any one of [1] to

[17] and

[19] , wherein the produced powder is a powder of a magnesium-based alloy.

[0377] The method according to any of [1] to

[17] and

[19] , wherein the produced powder is a powder of an alloy consisting of magnesium.

[0378] A method component according to any of [1] to

[17] and

[19] , wherein the produced powder is a powder of an alloy consisting of magnesium as a majority component.

[0379] The method according to any of [1] to

[17] , wherein the produced powder is a lithium-based alloy powder.

[0380] The method according to any one of [1] to

[17] , wherein the produced powder is a powder of an alloy consisting of lithium.

[0381] The method according to any one of [1] to

[17] , wherein the produced powder is a powder of an alloy consisting of lithium as a majority component.

[0382] The method according to any one of [1] to

[17] and

[23] , wherein the produced powder is a powder of a copper-based alloy.

[0383] The method according to any one of [1] to

[17] and

[23] , wherein the produced powder is a powder of an alloy consisting of copper.

[0384] The method according to any one of [1] to

[17] and

[23] , wherein the produced powder is a powder of an alloy consisting of copper as a majority component.

[0385] The method according to any one of [1] to

[17] and

[22] , wherein the produced powder is a powder of a cobalt-based alloy.

[0386] The method according to any one of [1] to

[17] and

[22] , wherein the produced powder is a powder of an alloy consisting of cobalt.

[0387] The method according to any of [1] to

[17] and

[22] , wherein the powder produced is a powder of an alloy having a majority component of cobalt.

[0388] The method according to any of [1] to

[0387] , wherein a vacuum is applied in the chamber after the metal has melted and before atomization.

[0389] The method according to any of

[0388] to

[0389] , wherein the applied vacuum is equal to or greater than 0.9 mbar.

[0390] The method according to any of

[0388] to

[0389] , wherein after the vacuum is applied the chamber is refilled with an inert atmosphere before atomization begins.

[0391] The method according to any of

[0390] , wherein the inert atmosphere consists of an inert gas.

[0392] The method according to any of

[0388] to

[0391] , wherein at least two rinse cycles are performed, achieving a vacuum level in each cycle and then refilling with the inert atmosphere gas.

[0393] The method according to any of

[0388] to

[0392] , wherein a cheaper gas is used in the intermediate rinses.

[0394] The method according to any of

[0388] to

[0389] , wherein after applying the vacuum the chamber is refilled with gas before spraying begins.

[0395] The method according to

[0394] , wherein the gas used to refill the chamber after applying the vacuum contains not more than 98 ppm by volume of oxygen.

[0396] The method according to

[0394] , wherein the gas used to refill the chamber after applying the vacuum contains not more than 98 ppm by volume of nitrogen.

[0397] A method according to

[0394] , wherein the gas used to refill the chamber after applying the vacuum contains not more than 4 ppm by volume of hydrogen.

[0398] A method according to any of

[0394] to

[0397] , wherein at least two rinse cycles are performed, achieving a vacuum level in each cycle and then refilling the gas.

[0399] A method according to any of

[0394] to

[0398] , wherein a cheaper gas is used in the intermediate rinses.

[0400] A method according to any of [1] to

[0399] , wherein the atomization system used to atomize the composition constitutes a melting chamber.

[0401] A method according to

[0400] , wherein the melting chamber constitutes at least one oxygen trap.

[0402] A method according to any of [1] to

[0401] , wherein the atomization chamber consists of at least one oxygen trap.

[0403] A method according to any of

[0401] to

[0402] , wherein the oxygen trap consists of a titanium alloy.

[0404] The method according to any one of

[0401] to

[0403] , wherein the oxygen trap comprises a magnesium alloy.

[0405] The method according to any one of

[0401] to

[0404] , wherein the oxygen trap comprises an aluminum alloy.

[0406] The method according to any one of

[0401] to

[0405] , wherein the oxygen trap comprises a silicon alloy.

[0407] The method according to any one of

[0401] to

[0406] , wherein the oxygen trap comprises a scandium alloy.

[0408] The method according to any one of

[0401] to

[0407] , wherein the oxygen trap comprises a zirconium alloy.

[0409] The method according to any one of

[0401] to

[0408] , wherein the oxygen trap is constructed of a hafnium alloy.

[0410] The method according to any one of

[0401] to

[0409] , wherein the oxygen trap comprises an alloy that is more reactive to oxygen than silicon according to the Elihan diagram for the processing conditions.

[0411] A method according to any one of

[0401] to

[0410] , wherein the oxygen trap is heated to above 120° C.

[0412] A method according to any one of

[0401] to

[0410] , wherein the oxygen trap is heated above the lowest oxide sublimation temperature of the alloy of the oxygen trap.

[0413] A method according to any one of [1] to

[0412] , wherein the oxygen content in the spray chamber is maintained below 280 ppm by volume before spraying begins.

[0414] A1s The oxygen content in the spray chamber was measured in ppm per volume. * PA2 and A1i * A method according to any of [1] to

[0413] that is between A1s and PA2.

[0415] A1s is 4.4 10 -5 The method according to

[0414] , where A1i is 9.2 10 -7 The method according to

[0414] , wherein the oxygen content is maintained according to any of

[0414] to

[0416] .

[0417] The method according to any of [1] to

[0413] , wherein the oxygen content is maintained according to any of

[0414] to

[0416] .

[0418] The method according to any of [1] to

[0417] , wherein the atmosphere in the chamber consists of nitrogen.

[0419] The method according to any of [1] to

[0418] , wherein the nitrogen content in the atomization chamber is less than 280 ppm by volume.

[0420] The method according to any of [1] to

[0417] , wherein the nitrogen content in the atomization chamber is maintained according to

[0419] before atomization begins.

[0421] The method according to any of [1] to

[17] , wherein a molybdenum alloy steel powder is produced.

[0422] The method according to

[17] , wherein a molybdenum alloy steel powder having a %Cr content of less than 2.9 wt% is obtained.

[0423] The method according to any of [1] to

[0422] , wherein the atmosphere in the chamber is changed to increase the surface tension between the molten composition and the spray disc.

[0424] The method according to

[0423] , wherein the increase in surface tension is at least 55 mN / m over the surface tension in air.

[0425] The method according to any of [1] to

[0424] , wherein the spray chamber consists of a cooling liquid.

[0426] The method according to

[0425] , wherein less than 0.9 l / s of cooling liquid contacts the spray disc during the spraying process.

[0427] The method according to any of [1] to

[0425] , wherein no cooling liquid contacts the spray disc during the spraying process.

[0428] The method according to any of [1] to

[0427] , wherein a gas is injected into the spray chamber.

[0429] The method according to any of [1] to

[0429] , wherein the increase in surface tension is at least 55 mN / m over the surface tension in air. 3The method according to

[0428] , wherein less than 1 / s contacts the atomized powder after it leaves the spray disk during the atomization process.

[0430] The method according to any of [1] to

[0429] , wherein the powder produced has a sphericity of 78% or more.

[0431] The method according to any of [1] to

[0429] , wherein the powder produced has a sphericity of 86% or more.

[0432] The method according to any of [1] to

[0429] , wherein the powder produced has a sphericity of 97% or more.

[0433] The method according to any of

[0430] to

[0432] , wherein the sphericity is measured by light scattering diffraction.

[0434] The method according to any of [1] to

[0433] , wherein the powder produced has a porosity level of 38% or less by volume.

[0435] The method according to any of [1] to

[0433] , wherein the powder produced has a porosity level of 18% or less by volume.

[0436] The powder produced is D of 780 microns or less. 50

[0436] The method according to any one of [1] to

[0435] , wherein the powder produced has a D50 of 380 microns or less.

[0438] D50 refers to the particle size that occupies 50% of the volume of the sample. 50 The method according to any one of

[0436] to

[0437] , wherein the cumulative distribution of particle sizes is made up of smaller particles, as measured by laser diffraction in accordance with ISO 133320-2009.

[0440] The method according to any one of [1] to

[0435] , wherein the composition of at least one metal provided in step a) is an alloy having a higher oxygen affinity in air at room temperature than aluminum according to the Ellingham diagram.

[0441] The method according to any one of [1] to

[0435] , wherein the composition of at least one metal provided in step a) is an alloy cutting the Y-axis of the Ellingham diagram below t-210 Kcal.

[0442] The method according to any one of [1] to

[0443] , wherein the composition of at least one metal provided in step a) is an alloy having a higher oxygen affinity in air at room temperature according to the Ellingham diagram than aluminum according to the Ellingham diagram. 3

[0442] The method according to any of [1] to

[0435] , wherein the composition of at least one metal provided in step a) is a low melting point alloy having a melting point of 590°C or less.

[0443] A lithium-based alloy powder produced according to any of the methods of [1] to

[17] .

[0444] A lithium-based alloy powder produced according to any of the methods of [1] to

[17] , comprising %Mg of 3.2wt% or more.

[0445] A lithium-based alloy powder produced according to any of the methods of [1] to

[17] , comprising aluminium.

[0446] A lithium-based alloy powder produced according to any of the methods of [1] to

[17] , comprising %Al of 3.2wt% or more.

[0447] A lithium-based alloy powder produced according to any of the methods of

[0443] to

[0446] , wherein the majority of the component is lithium.

[0448] A magnesium-based alloy powder produced according to any one of the methods from [1] to

[17] .

[0449] A magnesium-based alloy powder produced according to any one of the methods from [1] to

[17] , containing %Li at 3.2wt% or more.

[0450] A magnesium-based alloy powder produced according to any one of the methods from

[0448] to

[0449] , the majority of the components being magnesium.

[0451] An aluminum-based alloy powder produced according to any one of the methods from [1] to

[18] .

[0452] An aluminum-based alloy powder produced according to any one of the methods from [1] to

[18] , containing %Li at 3.2% or more.

[0453] A gallium-based alloy powder produced according to any one of the methods from [1] to

[17] .

[0454] A gallium-based alloy powder produced according to any one of the methods from [1] to

[17] , containing molten metal (%MM) at 3.2wt% or more.

[0455] A gallium-based alloy according to

[0454] , wherein MM is aluminium.

[0456] A gallium-based alloy according to

[0454] , wherein MM is nickel.

[0457] A gallium-based alloy according to

[0454] , wherein MM is titanium.

[0458] A gallium-based alloy according to

[0454] , wherein MM is iron.

[0459] A gallium-based alloy according to

[0454] , wherein MM is cobalt.

[0460] A gallium-based alloy powder according to any of

[0453] to

[0459] , the majority of the component being gallium.

[0461] An aluminum-based alloy powder produced according to any one of the methods [1] to

[17] consisting of gallium.

[0462] An aluminum-based alloy powder produced according to any one of the methods [1] to

[17] containing %Ga at 3.2 wt% or more.

[0463] An aluminum-based alloy powder according to any one of the methods

[0461] to

[0462] , the majority of the component being aluminum.

[0464] A titanium-based alloy powder produced according to any one of the methods [1] to

[17] consisting of gallium.

[0465] A titanium-based alloy powder produced according to any one of the methods [1] to

[17] containing %Ga at 3.2 wt% or more.

[0466] A titanium-based alloy powder according to any one of the methods

[0464] to

[0465] , the major component being titanium.

[0467] An iron-based alloy powder produced according to any one of the methods [1] to

[17] and

[20] consisting of gallium.

[0468] An iron-based alloy powder produced according to any one of the methods [1] to

[17] and

[20] , comprising 3.2 wt% Ga or more.

[0469] An iron-based alloy powder produced according to any one of the methods

[0467] to

[0468] , comprising a majority of iron.

[0470] A nickel-based alloy powder produced according to any one of the methods [1] to

[17] and

[19] , comprising gallium.

[0471] A nickel-based alloy powder produced according to any one of the methods [1] to

[17] and

[21] , comprising 3.2 wt% Ga or more.

[0472] A nickel-based alloy powder produced according to any one of the methods

[0470] to

[0471] , comprising a majority of nickel.

[0473] A cobalt-based alloy powder produced according to any one of the methods [1] to

[17] and

[22] , comprising gallium.

[0474] A cobalt-based alloy powder produced according to any of the processes [1] to

[17] and

[22] containing %Ga equal to or more than 3.2 wt%.

[0475] A cobalt alloy according to any of the processes

[0473] to

[0474] , the majority of the constituent being cobalt.

[0476] Operation of a process according to any of the processes [1] to

[0475] to produce a powder.

[0477] A molybdenum alloy steel powder produced according to any of the processes [1] to

[17] , having %Cr limited to or less than 2.9 wt%.

[0478] The method according to any of

[0255] ,

[0256] ,

[0338] ,

[0349] ,

[0353] and

[0439] , wherein the room temperature is 23±2° C.

[0479] The method according to any of [1] to

[0435] and

[0439] to

[0478] , wherein the powder produced is a particulate matter.

[0480] The method according to

[0479] , wherein the particulate matter is a powder having a diameter of 1000 microns or less.

[0481] The method according to any of

[19] to

[23] ,

[34] to

[38] ,

[44] ,

[50] ,

[0106] ,

[0112] ,

[0128] ,

[0129] ,

[0150] ,

[0151] ,

[0194] ,

[0195] ,

[0226] ,

[0263] to

[0267] and

[0269] , wherein the composition to be sprayed is a composition consisting of at least one metal provided in step a).

[0482] The method according to any of

[60] ,

[0133] ,

[0234] ,

[0316] ,

[0319] ,

[0320] ,

[0321] ,

[0350] and

[0356] , wherein the shaft is a main shaft.

[0484] The method according to any of [1] to

[0483] , wherein the spray disc is a spray rotor.

[0485] A method according to any one of

[0369] to

[0484] , wherein the majority component is the component having a higher weight proportion.

[0058] Any embodiment disclosed herein may be combined with any other embodiment in any combination provided they are not mutually exclusive.

[0059] Working Example Example 1 A setup as shown in Figure 2 was manufactured with a metal structure around a disk (2) made of molybdenum alloy TZM, a disk (1) made of Ti2O3, and a shaft made of nickel alloy (Inconel 718). The radius of the disk was 80 mm. The cylindrical part of the disk and the corresponding cylindrical part of the metal structure in contact with the disk were N1 polished before assembly. The assembly tolerance was H7-G8. The steady-state average processing temperature at the ceramic and metal structure interface was evaluated to be 1420 °C. With this setup, an iron-based alloy was sprayed with the following composition: %Mn=0.92%; %Mo=3.02%; %V=0.46%; %P=0.005%; %S=0.0008% Others including %Fe and trace elements (wt%). Spraying was performed at 38000 rpm in a 9 bar Ar atmosphere with an oxygen content of 18 ppm by volume. D was obtained in 1 h 58 min. 50 produced 6400 kg of 26 micron powder. Figure 3(c) is a scanning electron micrograph (SEM) of the iron-based alloy powder obtained using the atomization parameters disclosed above.

[0060] For comparison, the iron-based alloy was sprayed using a similar set-up as described above in Example 1, but in this case with an 80 mm diameter atomizer disk operating at 18500 rpm in an Ar atmosphere at 1.1 bar, giving a PA2 value of 2.9·10 6 The powder produced had a characteristic size D of 97 microns. 50 Figure 5 shows a scanning electron micrograph (SEM) of the iron-based alloy powder produced using the atomization parameters mentioned above. As shown in Figure 5, the powder produced has significant collision and crushing particles with satellites attached to the main particles. The presence of such particles makes classification and separation of the powder difficult.

[0061] Example 3 The setup shown in Figure 2 was manufactured with a metal structure around a disk (2) made of molybdenum alloy TZM, a disk (1) made of alumina and a shaft made of nickel alloy (Inconel 718). The radius of the disk was 80 mm. Both the cylindrical part of the disk and the corresponding cylindrical part of the metal structure in contact with the disk were N1 polished before mounting. The assembly tolerance was H7 to G8. The average steady-state processing temperature at the interface of the ceramic and metal structure was evaluated as 730 °C. The setup was operated to atomize a scandium-containing aluminum alloy with the following composition (wt%): %Mg=4.6wt%; %Sc=0.78wt%; %Zr=0.4wt%; %Mn=0.5wt%; %Si=0.3wt%; %Fe=0.2wt% and others including %Al and trace elements. Atomization was performed at 28000 rpm in a 6 bar Ar atmosphere, producing 2200 kg of powder with a D50 of 48 microns in 1 hour 46 minutes and an oxygen content of 0.5 ppm by volume.

[0062] Example 4 A setup as shown in Figure 4(c) was produced with the metallography around the disk (2) made of molybdenum alloy TZM, the disk (1) made of vanes Al2O3 and the shaft made of nickel-based alloy (Inconel 718). The radius of the disk was 50 mm. Both the cylindrical part of the disk and the corresponding cylindrical part of the metal structure in contact with the disk were N1 polished before mounting. The mounting tolerance was H7-G8. With this setup, an aluminum alloy with the following composition was atomized: %Si=9.4; %Fe=0.3; %Cu=0.03; %Mn=0.3; %Mg=0.3; %Zn= 0.06; others including %Al and trace elements. Atomization was performed with the vaned disk at an angular speed of 42000 rpm in a nitrogen atmosphere at 1.6 bar with an oxygen content of less than 3.0 ppm by volume, and D 50 produced 590 kg / h of 69 micron powder.

[0063] Example 5 A magnesium-based alloy was atomized using the ceramic disk and metal shaft shown in Figure 4(a) as the atomizing element. The atomization system included two bearings with 25° angular contact and ceramic rotors. 0.39 m of cooling gas was injected into the atomization chamber during atomization. 3 / min and the nebulization system was cooled. 50 produced 32 micron powder, 360 kg / h.

[0064] Example 6 An aluminum-based alloy was atomized using a monolithic disk and shaft made of stainless steel (AISI 304) as shown in Figure 4(b). The disk was coated with titanate. The aluminum alloy was melted and atomized in a mixed atmosphere of argon and nitrogen at an angular speed of 28,000 rpm. D 50 produced a fine powder of 56 microns. Figure 3(a) is a scanning electron micrograph (SEM) of the aluminum-based alloy powder produced using the aforementioned atomization parameters.

[0065] Example 7 A metal-based alloy was atomized in an atomization system with two bearings with an angular contact of 31°. The hardness of the metal rings of the bearings was measured after exposure to 103°C for 50 minutes. The measurements were performed at 24°C according to ASTM E18-18a, resulting in a hardness of 56HRc. 50 produced 425 kg / h of 39 micron powder.

[0066] Example 8 A tool steel used in demanding cold work applications was manufactured using metallic disks and shafts made of nickel-based alloy (Inconel 718). The disks were coated with a multi-layer coating (2 layers) consisting of a first layer made of metal (NiCrAlY) 96 microns thick and a top ceramic layer (mixture of Zr-Y oxides) 385 microns thick. The coating layers were applied by thermal spraying with a roughness of 5 microns finish. The pressure in the spray chamber was 3.8 bar. D 50 produced fine tool steel powder of 42 microns. Figure 3(d) is a scanning electron micrograph (SEM) of the tool steel powder produced using the aforementioned atomization parameters.

[0067] Example 9 %Co=62.1; %Cr=28.9; %Mo=6.4; %Si=0.7; %Mn= 0.5; %Fe= 0.4 A CoCrMo superalloy with this composition, including other trace elements, was atomized using the setup shown in FIG. 4(c). In this case, the metallography around the disk (2) was produced using a molybdenum-based alloy, while the shaft was produced using a refractory superalloy. The implementation conditions were similar to those described in Examples 1, 3 and 4. Atomization was carried out using a ceramic disk with projections (TiN) in a closed atomization chamber operating at 2.6 bar. The sphericity of the powder produced was 98.2%.

[0068] Example 10 A tin-based solder alloy was successfully produced and processed using a metal disk with a diameter of 215 mm. The composition to be sprayed was superheated at a temperature of 206 °C, which is higher than the melting point of such a composition. The surface tension value between the liquid alloy and the disk was 790 mN / m. The surface tension value between the liquid alloy and the disk was determined using the sessile drop method. This method was based on the description in ISIJ Int., 55 (2015) from page 1642 (CJ Xuan, H. Shibata, Z. Zhao, PG Joensson and K. Nakajima) and the description in ISIJ Int., 55 (2015) from page 1882 (CJ Xuan, H. Shibata, S. Sukenaga, PG Joensson and K. Nakajima). The obtained stabilized surface tension value is the first measurement in which the surface tension shows a fluctuation smaller than the threshold value (50 mN / m) within 100 seconds after recording. This resulted in a powder with a powder size D50 of 39 microns. Figure 3(b) shows a scanning electron micrograph (SEM) of the Sn-based solder alloy obtained using the aforementioned atomization parameters.

[0069] Example 11 Metal disks and shafts made of refractory steel alloys were used to atomize copper-based alloys. The disks were coated with ceramic to protect them. The copper-based alloys were heated to a temperature 135°C higher than their melting temperature (Tm=994°C). Atomization was performed in an atomization chamber equipped with an oxygen trap made of titanium alloy, so that the oxygen content during atomization was 0.7 ppm by volume or less. The powder produced had a sphericity of 92% or more.

[0070] Example 12 Table 1 below identifies suitable contact angle measurements (contact angle between the disk material and the molten metal of 106 degrees or more and 168 degrees or less) for a given disk material and a given molten material.

[0071] [Table 1] The contact angle between the molten metal and the disk was measured using the sessile drop method. This method was based on the description in ISIJ Int.,55(2015) p.1642 (CJ Xuan, H. Shibata, Z. Zhao, PG Joensson and K. Nakajima) and ISIJ Int.,55(2015) p.1882 (CJ Xuan, H. Shibata, S. Sukenaga, PG Joensson and K. Nakajima). The measured contact angle was the stabilized value 500 seconds after the moment of complete melting.

[0072] Example 13 Table 2 below identifies suitable contact angle measurements (surface tension between the molten metal and the disk material of 780 mN / m or more and 1750 mN / m or less) for a given disk material and a given molten material.

[0073] [Table 2] The surface tension between the molten metal and the disk was measured using the sessile drop method, which was based on the description in ISIJ Int.,55(2015) p.1642 (CJ Xuan, H. Shibata, Z. Zhao, PG Joensson and K. Nakajima) and ISIJ Int.,55(2015) p.1882 (CJ Xuan, H. Shibata, S. Sukenaga, PG Joensson and K. Nakajima). The stabilized surface tension value obtained was the first measured value in which the surface tension showed a fluctuation smaller than the threshold value (50 mN / m) within 100 seconds after recording.

[0074] Example 14 The following composition disclosed in Table 3 was used for spray chamber absolute pressure between 1.2 and 29.6 bar, oxygen content between 0.8 and 18 ppm, parameter PA2 between 4.5 and 10 6 Over 70·10 6 In an inert atmosphere of 50 This was done to confirm whether spherical powder (sphericity over 94%) with a diameter of 1 mm or less (<75 mm) could be sprayed properly.

[0075] [Table 3-1]

[0076] [Table 3-2]

[0077] [Table 3-3]

[0078] [Table 3-4]

[0079] [Table 3-5]

[0080] [Table 3-6] Trace elements total less than 0.9 wt% Ten compositions were identified within the given range.

Claims

1. A method for producing metal-based alloy powder by centrifugal spraying in a sealed chamber, a) Providing a composition comprising at least one metal, b) A step of melting the composition, c) A step of atomizing the molten composition using a spray disc by centrifugal spraying, It has, The atmosphere inside the sealed spray chamber is pressurized or cooled. PA3 is less than 10000, and here PA3 = PA1 / P, and PA1 = ρ * N 2 * d 2, A method wherein ρ is the density of the composition sprayed at its melting point under an absolute pressure of 1 bar, measured in kg / m³ units, N is the rotational speed of the spray disk in rad / s units, d is the diameter of the spray disk in m units, and P is the pressure inside the spray chamber in Pa units.

2. The method according to claim 1, wherein PA3 is less than 1000.

3. PA2 is greater than 4,500,000, and here PA2 = K1 ＊ PA1 + K2 ＊ P is, P is the absolute pressure inside the spray chamber in units of Pa. PA1 = ρ ＊ N ２＊ d ２ And here ρ is kg / m ３ The density of the atomized composition at its melting point under an absolute pressure of 1 bar, measured in units of 1 bar, where N is the rotational speed of the spray disc in units of rad / s, and d is the diameter of the spray disc in units of m. The method according to claim 1 or 2, wherein K1 = 0.0033 and K2 = 22 at 1 / Pa.

4. The method according to any one of claims 1 to 3, wherein the absolute pressure in the spray chamber is greater than 1.2 bar.

5. The method according to any one of claims 1 to 4, wherein the absolute pressure in the spray chamber is less than 999.4 bar.

6. The method according to any one of claims 1 to 5, wherein the molten composition is superheated to a temperature at least 10°C higher than Tm and less than 396°C + Tm, where Tm is the melting temperature of the composition to be sprayed.

7. The method according to any one of claims 1 to 6, wherein the contact angle between the molten composition and the spray disc is greater than 96° and less than 168° when measured using the droplet method.

8. The method according to any one of claims 1 to 7, wherein the spray disc is made of ceramic and is supported by a metal cage structure.

9. The method according to any one of claims 1 to 8, wherein the spray chamber has at least one bearing having an angular contact of 15.5° or more and 34° or less.

10. The spray chamber has at least one bearing including at least one ring, The method according to any one of claims 1 to 9, wherein the hardness of the ring after exposure to 85°C or higher for 35 minutes or more is 54 HRc or higher.

11. The method according to any one of claims 1 to 10, wherein the surface tension between the molten composition and the surface of the spray disc, as measured by the droplet method, is greater than 780 mN / m and less than 1750 mN / m.

12. To locally cool the aforementioned spraying system, 0.012 m ３ The method according to any one of claims 1 to 11, wherein gas is introduced into the spray chamber at a flow rate of / min or more.

13. The method according to any one of claims 1 to 12, wherein the spray chamber has an oxygen trap, and before spraying is started, the oxygen content is maintained at 280 ppm or less by volume.

14. The method according to any one of claims 1 to 13, wherein the composition provided in step a) is selected from iron-based alloys, aluminum-based alloys, nickel-based alloys, copper-based alloys, cobalt-based alloys, magnesium-based alloys, silver-based alloys, germanium-based alloys, gold-based alloys and / or lithium-based alloys.

15. The method according to any one of claims 1 to 14, wherein the spray disc is made of a material containing metal.

16. The method according to any one of claims 1 to 15, wherein the spray disc is made of a material including ceramic.

17. The method according to any one of claims 1 to 16, wherein the spray disc is at least partially covered by two or three or more coating layers of different compositions.

18. The method according to any one of claims 1 to 17, further comprising using a jet of cooling gas, a fluid, or a cooling curtain.

19. The atomized powder is 9.6 × 10 ４ The method according to any one of claims 1 to 18, wherein the cooling is performed at a cooling rate of less than °C / s.

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