A nanoparticle-reinforced composite metal powder gas atomization device and atomization spray disc

Abstract

The present application belongs to the technical field of metal additive manufacturing, and discloses a nanoparticle-reinforced composite metal powder gas atomization device and an atomizing spray plate, wherein a first nozzle is used to spray a mixed gas to crush a metal melt while mixing the metal melt with nanoparticles to form a nanoparticle composite metal liquid mass, wherein a crushing structure is provided in the flow channel of the first nozzle to crush nanoparticle agglomerates in the mixed gas and further blend the mixed gas, thereby improving the uniformity of distribution of nanoparticles in the mixed gas, and further improving the uniformity of distribution of nanoparticles in the nanoparticle composite metal liquid mass; finally, a second nozzle is used to spray an atomizing gas to further crush and atomize the nanoparticle composite metal liquid mass to obtain a nanoparticle-reinforced composite metal powder that meets size requirements; therefore, uniform distribution of nanoparticles can be achieved in a one-time atomization preparation process.

Description

Technical Field

[0001] The present application relates to the technical field of metal additive manufacturing, and in particular to a nanoparticle-reinforced composite metal powder gas atomization device and an atomization spray disc. Background Art

[0002] Nanoparticle-reinforced composite metal powders have significant advantages in the field of additive manufacturing, especially in laser selective melting (SLM) technology. The addition of nanoparticles can refine the grains of the metal substrate, eliminate the preferred orientation of the microstructure, and promote the recrystallization process, ultimately improving the performance of SLM printed parts.

[0003] However, the traditional atomization process faces many challenges in preparing nanoparticle-reinforced composite metal powders. Nanoparticles tend to agglomerate and have a large density difference with the metal substrate, resulting in uneven distribution of nanoparticles in the composite powder, which affects the quality of the final product.

[0004] In addition, there are many problems with the post-processing process of mixing nanoparticles with metal substrate powder. This method easily introduces impurities, causing oxidation of the metal substrate powder, and it is difficult to ensure the uniform dispersion of nanoparticles. It may even reduce the sphericity of the composite powder, which is not conducive to subsequent processing and molding.

[0005] In order to overcome these problems, it is necessary to develop a technical solution that can achieve uniform distribution of nanoparticles in a one-time atomization preparation process. In the prior art, it is difficult to solve the problems of nanoparticle agglomeration and uneven distribution in the one-time preparation of nanoparticle-reinforced composite metal powders, and the post-processing process has defects such as introduction of impurities, oxidation, and poor dispersibility. Therefore, a new atomization spray disc structure and gas atomization equipment are urgently needed to solve these problems. In view of the above problems, the prior art urgently needs to be improved. Summary of the invention

[0006] The purpose of the present application is to provide a nanoparticle-reinforced composite metal powder gas atomization device and an atomization spray disc, which can achieve uniform distribution of nanoparticles in a one-time atomization preparation process.

[0007] In the first aspect, the present application provides an atomizing spray disc, comprising a spray disc base, a through hole being provided at the center of the spray disc base, the through hole being used for allowing metal melt to pass through; a first nozzle and a second nozzle are provided in the spray disc base, the first nozzle being located on the upper side of the second nozzle; the first nozzle is used to spray a mixed gas formed by a mixture of nanoparticles and an atomizing gas, so as to break up the metal melt to form a nanoparticle composite metal liquid mass; the second nozzle is used to spray an atomizing gas to further break up and atomize the nanoparticle composite metal liquid mass; a breaking structure is provided in the flow channel of the first nozzle, the breaking structure being used to break up the nanoparticle agglomerates in the mixed gas and to further mix the mixed gas.

[0008] A first nozzle is used to spray a mixed gas to break up the molten metal while mixing the molten metal with nanoparticles to form a nanoparticle composite metal liquid mass, wherein a breaking structure is provided in the flow channel of the first nozzle to break up the nanoparticle agglomerates in the mixed gas and further blend the mixed gas, thereby improving the uniformity of the distribution of the nanoparticles in the mixed gas, thereby improving the uniformity of the distribution of the nanoparticles in the nanoparticle composite metal liquid mass; finally, a second nozzle is used to spray an atomizing gas to further break up and atomize the nanoparticle composite metal liquid mass to obtain a nanoparticle-reinforced composite metal powder that meets the size requirements; therefore, uniform distribution of the nanoparticles can be achieved in a one-time atomization preparation process.

[0009] Optionally, the crushing structure includes a plurality of screens arranged along the flow direction of the airflow, and grid lines of adjacent screens are staggered with each other.

[0010] Preferably, the screen comprises a plurality of transverse grid lines and a plurality of longitudinal grid lines, and the plurality of transverse grid lines and the plurality of longitudinal grid lines intersect each other perpendicularly to form a plurality of rectangular meshes, the transverse grid lines of each screen are parallel to each other, and the longitudinal grid lines of each screen are parallel to each other; the transverse grid lines of any adjacent screens are longitudinally offset and the offset distance is half of the longitudinal dimension of the rectangular mesh; the longitudinal grid lines of any adjacent screens are transversely offset and the offset distance is half of the transverse dimension of the rectangular mesh.

[0011] Preferably, the longitudinal offset distance between any adjacent transverse grid lines of the screen is not greater than 0.5 mm; the transverse offset distance between any adjacent longitudinal grid lines of the screen is not greater than 0.5 mm.

[0012] Optionally, the crushing structure includes a crushing body having a plurality of irregular microchannels inside, and the microchannels are connected to the upstream and downstream end surfaces of the crushing body.

[0013] Preferably, the diameter of the smallest circumscribed circle of any cross section of the microchannel is no greater than 0.5 mm.

[0014] Optionally, the crushing structure includes an upper substrate, a lower substrate, a plurality of upper rib needles arranged on the lower surface of the upper substrate, and a plurality of lower rib needles arranged on the upper surface of the lower substrate, the upper substrate is arranged on the upper wall of the flow channel of the first nozzle, the lower substrate is arranged on the lower wall of the flow channel of the first nozzle, and the upper rib needles and the lower rib needles are staggered with each other.

[0015] Preferably, the lengths of the upper rib needle and the lower rib needle are both 1 / 2-3 / 4 of the height of the flow channel at the local position of the flow channel where the upper rib needle is located.

[0016] Preferably, the flow channel of the first nozzle comprises an inlet section, a mixing section and an outlet section which are sequentially arranged along the air flow direction, and the crushing structure is arranged in the mixing section.

[0017] Preferably, the flow channel of the first nozzle is a contraction-type flow channel, and the length of the outlet section along the air flow direction is not greater than 5 mm.

[0018] Preferably, an insulating heat-insulating layer is provided between the upper and lower sides of the crushing structure and the spray plate base, and the crushing structure can heat the mixed gas.

[0019] The upper and lower sides of the crushing structure are provided with insulating and heat-insulating layers, which can insulate and prevent heat from being transferred to the spray plate base, thereby reducing heat loss and preventing the heat from being transferred to the spray plate base, causing the spray plate base to expand and contract under the action of heat, causing the flow channel size of the first nozzle and the second nozzle to change, thereby affecting the stability of the gas flow. The crushing structure can heat the mixed gas, which helps to reduce the agglomeration of nanoparticles and make the nanoparticles more evenly distributed in the metal melt. By heating the mixed gas, the superheat of the nanoparticle composite metal liquid mass can be increased, which helps to improve the uniformity and quality of the composite metal powder.

[0020] Preferably, the upper substrate is capable of applying ultrasonic excitation to the upper rib needles.

[0021] By applying ultrasonic excitation to the upper rib needle, the crushing effect of nanoparticle agglomerates in the mixed gas can be enhanced, and the distribution uniformity of nanoparticles in the composite metal liquid mass can be further improved, thereby solving the problem of uneven distribution of nanoparticles in nanoparticle-reinforced composite metal powders.

[0022] Preferably, the spray disc base includes a spray disc upper part, a spray disc middle part and a spray disc lower part, the spray disc upper part and the spray disc middle part are detachably connected, and the spray disc upper part and the spray disc middle part form the first nozzle, the spray disc lower part and the spray disc middle part are detachably connected, and the spray disc lower part and the spray disc middle part form the second nozzle.

[0023] Preferably, the crushing structure is detachably embedded in the flow channel of the first nozzle.

[0024] Preferably, the spray plate middle piece includes a middle piece upper piece, a middle piece lower piece and a replaceable gasket sandwiched between the middle piece upper piece and the middle piece lower piece.

[0025] In a second aspect, the present application provides a nanoparticle-reinforced composite metal powder gas atomization device, comprising a smelting chamber, an atomization chamber arranged at the lower side of the smelting chamber, a smelting crucible and a tundish are arranged in the smelting chamber, a guide nozzle is connected to the lower end of the tundish, the guide nozzle extends into the atomization chamber, the smelting crucible is used to smelt a metal substrate to obtain a molten metal, and the tundish is used to receive the molten metal obtained by the smelting crucible; the atomization spray disc mentioned above is arranged in the atomization chamber, the guide nozzle extends into the upper part of the through hole of the atomization spray disc or is arranged above the atomization spray disc and directly facing the through hole;

[0026] The nano-particle-reinforced composite metal powder gas atomization equipment further comprises a nano-particle adder, and the nano-particle adder is used to deliver the mixed gas to the atomizing spray disc.

[0027] Preferably, the nanoparticle additive includes a storage tank, a feeder, a carrier gas generator and a mixer; the storage tank is connected to the mixer via the feeder, the carrier gas generator and the atomizing spray disk are both connected to the mixer, the storage tank is used to store nanoparticles, the carrier gas generator is used to transport the atomizing gas to the mixer, the feeder is used to transport the nanoparticles in the storage tank into the mixer, and the mixer is used to mix the nanoparticles and the atomizing gas to form the mixed gas, and transport it to the atomizing spray disk.

[0028] Beneficial effect: The nanoparticle-reinforced composite metal powder gas atomization equipment and atomizing spray plate provided in the present application use a first nozzle to spray a mixed gas to crush the metal melt while mixing the metal melt with nanoparticles to form a nanoparticle composite metal liquid mass, wherein a crushing structure is set in the flow channel of the first nozzle to crush the nanoparticle agglomerates in the mixed gas and further mix the mixed gas, thereby improving the uniformity of the distribution of the nanoparticles in the mixed gas, and then improving the uniformity of the distribution of the nanoparticles in the nanoparticle composite metal liquid mass; finally, the second nozzle is used to spray atomizing gas to further crush and atomize the nanoparticle composite metal liquid mass to obtain a nanoparticle-reinforced composite metal powder that meets the size requirements; therefore, uniform distribution of nanoparticles can be achieved in a one-time atomization preparation process. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 A schematic diagram of the structure of an atomizing spray disc provided in an embodiment of the present application.

[0030] Figure 2 A schematic diagram of the structure of another atomizing spray disc provided in an embodiment of the present application.

[0031] Figure 3 Schematic diagram of an exemplary crushing structure.

[0032] Figure 4 This is a schematic diagram of the structure of the nanoparticle-reinforced composite metal powder atomization equipment provided in an embodiment of the present application.

[0033] Explanation of reference numerals: 1. spray plate base; 101. spray plate upper part; 102. spray plate middle part; 1021. middle part upper piece; 1022. middle part lower piece; 1023. gasket; 103. spray plate lower part; 2. through hole; 3. first nozzle; 301. inlet section; 302. mixing section; 303. outlet section; 4. second nozzle; 5. crushing structure; 501. upper base; 502. lower base; 503. upper rib needle; 504. lower rib needle; 6. first air inlet chamber; 7. second air inlet Gas chamber; 8. Insulating and heat-insulating layer; 100. Atomizing spray disc; 200. Melting chamber; 300. Atomizing chamber; 400. Melting crucible; 500. Tundish; 600. Diversion nozzle; 700. Nanoparticle adder; 71. Storage tank; 72. Feeder; 73. Carrier gas generator; 74. Mixer; 800. Powder collecting device; 81. First powder collecting tank; 82. Cyclone separator; 83. Second powder collecting tank; 84. Dust collector; 85. Third powder collecting tank; 86. induced draft fan. DETAILED DESCRIPTION

[0034] The technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all of the embodiments. The components of the embodiments of the present application described and shown in the drawings here can be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present application provided in the drawings is not intended to limit the scope of the application claimed for protection, but merely represents the selected embodiments of the present application. Based on the embodiments of the present application, all other embodiments obtained by those skilled in the art without making creative work belong to the scope of protection of the present application.

[0035] It should be noted that similar reference numerals and letters represent similar items in the following drawings, so once an item is defined in one drawing, it does not need to be further defined and explained in subsequent drawings. At the same time, in the description of this application, the terms "first", "second", etc. are only used to distinguish the description and cannot be understood as indicating or implying relative importance.

[0036] Nanoparticle-reinforced composite metal powder is a metal powder obtained by combining a metal substrate and nanoparticles. The presence of nanoparticles eliminates the preferred orientation of the microstructure of the metal substrate along a specific direction, accelerates heterogeneous nucleation, promotes the recrystallization process, hinders grain growth, and significantly refines the grains. The use of nanoparticle-reinforced composite metal powder is beneficial to improving the performance of SLM printed parts. However, when using the traditional atomization process to prepare nanoparticle-reinforced composite metal powder in one go, due to the serious agglomeration behavior of nanoparticles, the density difference between the base metal and the nanoparticles, etc., it is easy to cause the phenomenon of uneven distribution of nanoparticles and metal substrates in the nanoparticle-reinforced composite metal powder. The traditional post-treatment process of mixing nanoparticles and metal substrate powders will cause the introduction of impurities, oxidation of metal substrate powders, poor uniform dispersion of nanoparticles, and reduced sphericity of composite powders. How to achieve uniform distribution of nanoparticles in a one-time atomization preparation process has become a key technical problem in the preparation of nanoparticle-reinforced composite metal powders. In view of the above problems, the existing technology urgently needs to be improved.

[0037] Please refer to Figure 1-Figure 3In some embodiments of the present application, an atomizing spray disc 100 includes a spray disc base 1, a through hole 2 is opened at the center of the spray disc base 1, and the through hole 2 is used for metal melt to pass through; a first nozzle 3 and a second nozzle 4 are provided in the spray disc base 1, and the first nozzle 3 is located on the upper side of the second nozzle 4; the first nozzle 3 is used to spray a mixed gas formed by a mixture of nanoparticles and an atomizing gas (the atomizing gas is generally an inert gas, but not limited to this) to break up the metal melt to form nanoparticle composite metal liquid agglomerates (or nanoparticle composite metal droplets); the second nozzle 4 is used to spray an atomizing gas to further break up and atomize the nanoparticle composite metal liquid agglomerates (thereby reducing the size of the nanoparticle composite metal droplets); a breaking structure 5 is provided in the flow channel of the first nozzle 3, and the breaking structure 5 is used to break up the nanoparticle agglomerates in the mixed gas and further mix the mixed gas.

[0038] The first nozzle 3 is used to spray the mixed gas to break up the molten metal while mixing the molten metal with the nanoparticles, thereby forming a nanoparticle composite metal liquid mass, wherein a breaking structure 5 is provided in the flow channel of the first nozzle 3 to break up the nanoparticle agglomerates in the mixed gas and further mix the mixed gas, thereby improving the uniformity of the distribution of the nanoparticles in the mixed gas, thereby improving the uniformity of the distribution of the nanoparticles in the nanoparticle composite metal liquid mass; finally, the second nozzle 4 is used to spray the atomizing gas to further break up and atomize the nanoparticle composite metal liquid mass, thereby obtaining a nanoparticle-reinforced composite metal powder that meets the size requirements; therefore, the uniform distribution of the nanoparticles can be achieved in a one-time atomization preparation process.

[0039] There are various structures for realizing the crushing structure 5 to crush the nanoparticle agglomerates and further mix the mixed gas.

[0040] For example, in some embodiments, see Figure 2 The crushing structure 5 includes a plurality of screens arranged along the airflow direction, and the grid lines of adjacent screens are staggered with each other.

[0041] The screens in the crushing structure 5 are arranged in a staggered manner along the direction of the airflow. When the mixed gas passes through the crushing structure 5, the nanoparticles will frequently collide with the grid lines of the screens, so that the nanoparticle agglomerates are fully broken up, which can effectively break up the nanoparticle agglomerates in the mixed gas and make the crushed nanoparticles more fully mixed with the atomized gas, effectively improving the distribution uniformity of the nanoparticles in the mixed gas.

[0042] Optionally, the screen includes multiple transverse grid lines and multiple longitudinal grid lines (wherein the transverse and longitudinal directions are any directions within the mesh plane of the screen and the transverse direction is perpendicular to the longitudinal direction), and the multiple transverse grid lines and the multiple longitudinal grid lines are perpendicular to each other and cross each other to form multiple rectangular meshes (preferably square meshes), the transverse grid lines of each screen are parallel to each other, and the longitudinal grid lines of each screen are parallel to each other; the transverse grid lines of any adjacent screens are staggered in the longitudinal direction and the staggered distance is half of the longitudinal dimension of the rectangular mesh; the longitudinal grid lines of any adjacent screens are staggered in the transverse direction and the staggered distance is half of the transverse dimension of the rectangular mesh.

[0043] This screen arrangement is equivalent to forming multiple passages smaller than the rectangular mesh between two adjacent screens. The passages are 1 / 4 of the rectangular mesh, which can ensure that the airflow can be more evenly distributed when passing through each screen, and can further effectively mix the mixed gas, thereby enhancing the dispersion effect on the nanoparticles.

[0044] Furthermore, the longitudinal offset distance between any adjacent transverse grid lines of the screen is not greater than 0.5 mm; the transverse offset distance between any adjacent longitudinal grid lines of the screen is not greater than 0.5 mm. Thus, the size of the permeable channels between the screens is prevented from being too large, resulting in insufficient crushing of the nanoparticle agglomerates.

[0045] The screens may be arranged at intervals or in contact with each other, which may be specifically arranged according to actual needs.

[0046] The screens are not limited to being displaced in the horizontal and vertical directions, but may also be displaced in a rotational manner (the screens are rotated around the normal direction at different angles to form a rotational dislocation).

[0047] Or for example, in other embodiments, see Figure 1 The crushing structure 5 includes a crushing body having a plurality of irregular microchannels inside, and the microchannels connect the upstream and downstream end surfaces of the crushing body.

[0048] Through these irregular microchannels, the nanoparticle agglomerates in the mixed gas can be effectively broken up, and the mixed gas can be further blended to ensure the uniform distribution of the nanoparticles in the metal melt. This design of the breaking structure 5 can effectively break up the nanoparticle agglomerates in the mixed gas during the atomization process and further blend them. This design ensures the uniform distribution of the nanoparticles in the metal melt and solves the problem of uneven distribution of nanoparticles and metal substrates in the traditional atomization process.

[0049] The irregular microchannels in the fragmentation structure 5 may have varying sizes, angles, cross-sectional shapes, etc. at different positions along the flow direction, wherein each microchannel may have one or more connecting points. Through its unique shape and size, the mixed gas can pass through a complex flow path and flow field, thereby achieving effective fragmentation of nanoparticle agglomerates.

[0050] Preferably, the diameter of the smallest circumscribed circle of any cross section of the microchannel is no greater than 0.5 mm. Such a size design can ensure that the nanoparticle agglomerates are fully broken up when flowing through the microchannel.

[0051] For example, in other embodiments, see Figure 3 The crushing structure 5 includes an upper substrate 501, a lower substrate 502, a plurality of upper rib needles 503 arranged on the lower surface of the upper substrate 501, and a plurality of lower rib needles 504 arranged on the upper surface of the lower substrate 502. The upper substrate 501 is arranged on the upper wall of the flow channel of the first nozzle 3, and the lower substrate 502 is arranged on the lower wall of the flow channel of the first nozzle 3, and the upper rib needles 503 and the lower rib needles 504 are staggered with each other.

[0052] The nanoparticle agglomerates can be effectively broken up by the collision of the upper rib needles 503 and the lower rib needles 504 with the nanoparticle agglomerates. The design of the upper rib needles 503 and the lower rib needles 504 being offset from each other further increases the disturbance of the gas flow, causing the mixed gas to be more broken up and mixed during the flow process.

[0053] Preferably, the lengths of the upper rib needle 503 and the lower rib needle 504 are both 1 / 2-3 / 4 of the height of the flow channel at the local position of the flow channel where the rib needle is located (ie, the connection position between the rib needle and the flow channel of the first nozzle 3).

[0054] The length of the upper rib needle 503 and the lower rib needle 504 is designed to be 1 / 2-3 / 4 of the height of the flow channel at a local position of the flow channel, so as to ensure the crushing effect while not excessively hindering the gas flow.

[0055] The upper rib pins 503 and the lower rib pins 504 can be made of different materials to meet the wear resistance and corrosion resistance requirements under different working conditions. The shapes and sizes of the upper rib pins 503 and the lower rib pins 504 can also be optimized according to the specific flow channel design to further improve the crushing effect and reduce the gas flow resistance. In addition, the installation method of the upper substrate 501 and the lower substrate 502 can adopt a detachable structure to facilitate maintenance and replacement.

[0056] There are many ways to arrange the upper rib pins 503 and the lower rib pins 504 in a staggered manner. For example, in the projection of the upper rib pins 503 and the lower rib pins 504 on the horizontal plane, any one of the upper rib pins 503 is located at the distribution center of three lower rib pins 504 arranged in an equilateral triangle or at the distribution center of four lower rib pins 504 arranged in a square; conversely, any one of the lower rib pins 504 is also located at the distribution center of three upper rib pins 503 arranged in an equilateral triangle or at the distribution center of four upper rib pins 503 arranged in a square; but it is not limited thereto.

[0057] In some embodiments, see Figure 1 A first air inlet chamber 6 and a second air inlet chamber 7 are also provided in the spray plate base 1. The flow channel of the first nozzle 3 is connected to the first air inlet chamber 6, and the flow channel of the second nozzle 4 is connected to the second air inlet chamber 7; the first air inlet chamber 6 is used to be connected to an external mixed gas delivery device (such as the nanoparticle adder 700 described later) to input the mixed gas input by the external mixed gas delivery device into the flow channel of the first nozzle 3, or; the second air inlet chamber 7 is used to be connected to an external atomizing gas delivery device to input the atomizing gas input by the external atomizing gas delivery device into the flow channel of the second nozzle 4.

[0058] Generally, the first air inlet chamber 6 and the second air inlet chamber 7 are both annular air chambers, and the first nozzle 3 and the second nozzle 4 are both annular nozzles, so as to ensure that the metal melt can be broken and atomized uniformly along 360°.

[0059] In some preferred embodiments, see Figure 1 The flow channel of the first nozzle 3 includes an inlet section 301, a mixing section 302 and an outlet section 303 arranged in sequence along the air flow direction, and the crushing structure 5 is arranged in the mixing section 302. Through this design, the crushing structure 5 in the mixing section 302 can effectively crush and mix the nanoparticles and the atomized gas, ensuring uniform distribution of the nanoparticles in the metal liquid mass or metal droplets.

[0060] Preferably, the flow channel of the first nozzle 3 is a contraction-type flow channel, and the length of the outlet section 303 along the air flow direction is not greater than 5 mm.

[0061] Among them, the contraction flow channel can increase the flow rate of the mixed gas. On the one hand, it helps to fully mix the nanoparticles and the atomizing gas, and on the other hand, it can ensure that the metal melt can be reliably broken; on this basis, the length of the outlet section 303 is limited to within 5 mm, so as to avoid the nanoparticles from agglomerating again during the flow process due to the outlet section 303 being too long, which helps to maintain the stability and uniformity of the mixed gas during the injection process.

[0062] Among them, the flow channel of the second nozzle 4 can adopt a contraction type flow channel or a LAVAL type flow channel (mainly referring to its airflow acceleration section being a LAVAL type flow channel, and a transition section can be provided between the airflow acceleration section and the second air inlet chamber 7); preferably, it is a LAVAL type flow channel, which can form a supersonic atomizing airflow, so that the nano-particle composite metal liquid mass is broken and atomized into smaller droplets, thereby obtaining a finer metal powder.

[0063] When the crushing structure 5 adopts a mutually staggered screen or a crushing body with multiple irregular micro-channels, an insulating and heat-insulating layer 8 (such as Figure 2 As shown), and the crushing structure 5 can heat the mixed gas.

[0064] The upper and lower sides of the crushing structure 5 are provided with an insulating layer 8, which can insulate and prevent heat from being transferred to the spray plate base 1, thereby reducing heat loss and avoiding the heat being transferred to the spray plate base 1, which causes the spray plate base 1 to expand and contract under the action of heat, causing the flow channel size of the first nozzle 3 and the second nozzle 4 to change, thereby affecting the stability of the airflow (due to the small size of the airflow acceleration section of the flow channel in the atomizing spray plate 100, the influence of thermal expansion and contraction has a significant effect on the size of the airflow acceleration section of the flow channel, especially when the flow channel of the second nozzle 4 is a LAVAL type flow channel, the size of the flow channel throat is more significantly affected, and this effect will reduce the stability of the airflow). By heating the mixed gas, the superheat of the nanoparticle composite metal liquid mass can be increased, which helps to improve the uniformity and quality of the composite metal powder.

[0065] The insulating layer 8 can be made of various materials, such as ceramic fiber, glass fiber or other high temperature resistant insulating materials. There are many ways to heat the mixed gas. For example, a heating wire or a heating film can be set in the crushing structure 5 to heat the crushing structure 5, and then the crushing structure 5 heats the mixed gas; or, the crushing structure 5 itself is made of a conductive material, and the crushing structure 5 heats the mixed gas by energizing itself.

[0066] When the crushing structure 5 adopts a rib needle structure, the upper substrate 501 can be configured to apply ultrasonic excitation to the upper rib needles 503 .

[0067] By applying ultrasonic excitation to the upper rib needle 503, the upper rib needle 503 generates ultrasonic disturbance on the airflow, which can enhance the breakup effect of nanoparticle agglomerates in the mixed gas and further improve the uniformity of nanoparticle distribution in the composite metal liquid mass, thereby solving the problem of uneven distribution of nanoparticles in nanoparticle-reinforced composite metal powder.

[0068] The upper substrate 501 can apply ultrasonic excitation to the upper rib pins 503, which can be achieved in a variety of ways. For example, the upper substrate 501 can have a built-in ultrasonic generator to apply ultrasonic excitation to the upper rib pins 503 by converting electrical energy into mechanical vibration. Another way is to excite the upper substrate 501 through an external ultrasonic device and transmit it to the upper rib pins 503. Ultrasonic excitation can also be achieved by embedding piezoelectric material in the upper substrate 501 and controlling the vibration of the piezoelectric material through an electrical signal.

[0069] It should be noted that ultrasonic excitation is only applied to the upper rib needle 503. Due to the misalignment between the upper rib needle 503 and the lower rib needle 504, the ultrasonic disturbance cannot be directly transmitted to the second nozzle 4 through the rib needle. This can effectively reduce the impact of ultrasonic excitation on the flow channel in the second nozzle 4 (especially the airflow acceleration section in the flow channel), ensure its airflow stability, and further effectively ensure the stability of the metal powder particle size.

[0070] In some embodiments, see Figure 1 The spray disc base 1 includes a spray disc upper part 101, a spray disc middle part 102 and a spray disc lower part 103. The spray disc upper part 101 and the spray disc middle part 102 are detachably connected, and the spray disc upper part 101 and the spray disc middle part 102 surround the first nozzle 3 (and the first air inlet chamber 6). The spray disc lower part 103 and the spray disc middle part 102 are detachably connected, and the spray disc lower part 103 and the spray disc middle part 102 surround the second nozzle 4 (and the second air inlet chamber 7).

[0071] The detachable connection between the spray plate upper part 101 and the spray plate middle part 102 makes the cleaning and maintenance of the first nozzle 3 more convenient, and avoids the accumulation of nanoparticles in the first nozzle 3. The detachable connection between the spray plate lower part 103 and the spray plate middle part 102 also facilitates the maintenance of the second nozzle 4. Through this modular design, the various components of the atomizing spray plate 100 can be disassembled and replaced separately, further improving the service life and maintenance efficiency of the atomizing spray plate 100.

[0072] Preferably, the crushing structure 5 is detachably embedded in the flow channel of the first nozzle 3 .

[0073] The crushing structure 5 is detachably embedded in the flow channel of the first nozzle 3. This feature allows the crushing structure 5 to be easily removed and replaced when needed. Different crushing structures 5 can be replaced according to different types of nanoparticles to improve applicability. Through this design, it can be ensured that the nanoparticles and the metal melt are mixed more evenly during the preparation process, effectively solving the problem of uneven distribution of nanoparticles in the one-time atomization preparation process. At the same time, this detachable design is also helpful for maintaining and cleaning the nozzle, further improving production efficiency and product quality.

[0074] Specifically, there are many ways to embed the crushing structure 5. For example, the crushing structure 5 can be embedded in the flow channel of the first nozzle 3 by means of threaded connection, snap connection or magnetic adsorption. These connection methods are all characterized by convenient disassembly and replacement, and can be flexibly adjusted according to different production requirements. In addition, the material selection of the crushing structure 5 can also be diversified, and high temperature resistant and corrosion resistant materials can be selected to ensure its stability and durability in high temperature and high pressure environments.

[0075] In some preferred embodiments, see Figure 2 The spray plate middle piece 102 includes a middle piece upper piece 1021 , a middle piece lower piece 1022 , and a replaceable gasket 1023 sandwiched between the middle piece upper piece 1021 and the middle piece lower piece 1022 .

[0076] The gasket 1023 of different thicknesses can be easily replaced during use, thereby adjusting the distance between the first nozzle 3 and the second nozzle 4, and adjusting the air pressure distribution in the metal melt crushing atomization area to meet different atomization requirements. This design can effectively solve the problem of achieving uniform distribution of nanoparticles in a one-time atomization preparation process. Through this solution, the internal structure of the atomizing spray disc 100 can be flexibly adjusted according to actual needs before the atomization operation to ensure that the nanoparticles are evenly distributed in the metal melt, thereby improving the quality and performance of the nanoparticle-reinforced composite metal powder.

[0077] The replaceable gasket 1023 can be made of a variety of materials, such as high temperature resistant metal materials or composite materials, to meet different process requirements. Among them, when the crushing structure 5 can heat the mixed gas, the gasket 1023 is preferably a heat-insulating material to prevent heat from being transferred to the spray plate lower part 103 and affecting the size of the flow channel (especially the airflow acceleration section in the flow channel) of the second nozzle 4. When the upper substrate 501 can apply ultrasonic excitation to the upper rib needle 503, the gasket 1023 is preferably a vibration-isolating material to reduce the ultrasonic disturbance from being transferred to the spray plate lower part 103 and affecting the airflow stability of the second nozzle 4.

[0078] refer to Figure 4 The present application provides a nanoparticle-reinforced composite metal powder gas atomization device, comprising a smelting chamber 200, an atomizing chamber 300 arranged at the lower side of the smelting chamber 200, a smelting crucible 400 and a tundish 500 are arranged in the smelting chamber 200, a guide nozzle 600 is connected to the lower end of the tundish 500, the guide nozzle 600 extends into the atomizing chamber 300, the smelting crucible 400 is used to smelt a metal substrate to obtain a molten metal, and the tundish 500 is used to receive the molten metal obtained by the smelting crucible 400; the atomizing spray disc 100 mentioned above is arranged in the atomizing chamber 300, and the guide nozzle 600 extends into the upper part of the through hole 2 of the atomizing spray disc 100 or is arranged above the atomizing spray disc 100 and directly opposite to the through hole 2;

[0079] The nano-particle-reinforced composite metal powder gas atomization device further comprises a nano-particle adder 700 , which is used to deliver mixed gas to the atomizing spray disc 100 .

[0080] By using the atomizing spray disc 100 and introducing the nanoparticle adder 700, the nanoparticle-reinforced composite metal powder gas atomization equipment can achieve uniform distribution of nanoparticles in a one-time atomization preparation process, and obtain nanoparticle-reinforced composite metal powder with nanoparticles uniformly distributed in the metal matrix.

[0081] Specifically, see Figure 4 The nanoparticle adder 700 includes a storage tank 71, a feeder 72, a carrier gas generator 73 and a mixer 74; the storage tank 71 is connected to the mixer 74 through the feeder 72, the carrier gas generator 73 and the atomizing spray disc 100 are both connected to the mixer 74, the storage tank 71 is used to store nanoparticles, the carrier gas generator 73 is used to transport atomizing gas to the mixer 74, the feeder 72 is used to transport the nanoparticles in the storage tank 71 into the mixer 74, and the mixer 74 is used to mix the nanoparticles and the atomizing gas to form a mixed gas, and then transport it to the atomizing spray disc 100.

[0082] The feeder 72 may be a screw feeder, but is not limited thereto. The carrier gas generator 73 may include a liquefied gas tank (in which liquefied atomizing gas is stored), but is not limited thereto.

[0083] Specifically, the mixer 74 is connected to the first air inlet chamber 6 of the atomizing spray disc 100 through a pipeline.

[0084] Furthermore, the nanoparticle-reinforced composite metal powder atomization equipment also includes a powder collecting device 800, and the powder collecting device 800 is used to collect the formed nanoparticle-reinforced composite metal powder.

[0085] Specifically, see Figure 4 The powder collecting device 800 includes a first powder collecting tank 81 arranged at the lower end of the atomization chamber 300, a cyclone separator 82 whose air inlet is connected to the atomization chamber 300, a second powder collecting tank 83 arranged at the lower end of the cyclone separator 82, a dust collector 84 whose air inlet is connected to the air outlet of the cyclone separator 82, a third powder collecting tank 85 arranged at the lower end of the dust collector 84, and an induced draft fan 86 connected to the air outlet of the dust collector 84.

[0086] During operation, coarse powder with large particle size mainly falls into the first powder collecting tank 81, and fine powder will enter the cyclone separator 82 with the air flow under the suction force provided by the induced draft fan 86. The cyclone separator 82 further separates the fine powder in the air flow, and the separated fine powder will fall into the second powder collecting tank 83, while the ultrafine powder will enter the dust collector 84 with the air flow for filtration, and the filtered ultrafine powder will fall into the third powder collecting tank 85, and the filtered air flow will be discharged to the atmosphere or the subsequent exhaust gas treatment system.

[0087] In summary, the nanoparticle-reinforced composite metal powder gas atomization equipment and atomization spray disc of the present application have at least the following advantages:

[0088] 1. By providing a breaking structure 5 in the flow channel of the first nozzle 3, the nanoparticle agglomerates in the airflow are impacted and sheared, thereby breaking the nanoparticle agglomerates. The atomized gas and the nanoparticles can also be further mixed by the breaking structure 5, thereby improving the distribution uniformity of the nanoparticles in the mixed gas;

[0089] 2. The mixed gas is heated by the crushing structure 5 to increase the temperature of the mixed gas, thereby reducing the cooling effect of the mixed gas when crushing the molten metal, which helps to improve the atomization effect of the atomizing gas flow;

[0090] 3. The one-step formed nanoparticle-reinforced composite metal powder has a short preparation process, low process cost and short preparation time.

[0091] In this document, relational terms such as first and second, etc. are used merely to distinguish one entity or operation from another entity or operation, but do not necessarily require or imply any such actual relationship or order between these entities or operations.

[0092] The above description is only an embodiment of the present application and is not intended to limit the protection scope of the present application. For those skilled in the art, the present application may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. An atomizing spray disc, comprising a spray disc base (1), wherein a through hole (2) is provided at the center of the spray disc base (1), and the through hole (2) is used for allowing metal melt to pass through; characterized in that: The spray plate base (1) is provided with a first nozzle (3) and a second nozzle (4), wherein the first nozzle (3) is located on the upper side of the second nozzle (4); the first nozzle (3) is used to spray a mixed gas formed by mixing nanoparticles and atomizing gas to break up the metal melt to form nanoparticle composite metal liquid masses; the second nozzle (4) is used to spray atomizing gas to further break up and atomize the nanoparticle composite metal liquid masses; a breaking structure (5) is provided in the flow channel of the first nozzle (3), wherein the breaking structure (5) is used to break up nanoparticle agglomerates in the mixed gas and further mix the mixed gas; The crushing structure (5) comprises a plurality of screens arranged along the flow direction of the airflow, and the grid lines of adjacent screens are staggered with each other; The screen comprises a plurality of transverse grid lines and a plurality of longitudinal grid lines, wherein the plurality of transverse grid lines and the plurality of longitudinal grid lines intersect each other perpendicularly to form a plurality of rectangular meshes, the transverse grid lines of each screen are parallel to each other, and the longitudinal grid lines of each screen are parallel to each other; the transverse grid lines of any adjacent screens are longitudinally offset and the offset distance is half of the longitudinal dimension of the rectangular mesh; the longitudinal grid lines of any adjacent screens are transversely offset and the offset distance is half of the transverse dimension of the rectangular mesh.

2. The atomizing spray disc according to claim 1, characterized in that: The longitudinal offset distance between any adjacent transverse grid lines of the screen is not greater than 0.5 mm; the transverse offset distance between any adjacent longitudinal grid lines of the screen is not greater than 0.5 mm.

3. The atomizing spray disc according to claim 1, characterized in that: The flow channel of the first nozzle (3) comprises an inlet section (301), a mixing section (302) and an outlet section (303) arranged in sequence along the air flow direction, and the crushing structure (5) is arranged in the mixing section (302).

4. The atomizing spray disc according to claim 3, characterized in that: The flow channel of the first nozzle (3) is a contraction-type flow channel, and the length of the outlet section (303) along the airflow direction is no more than 5 mm.

5. The atomizing spray disc according to any one of claims 1 to 4, characterized in that: An insulating heat-insulating layer (8) is provided between the upper and lower sides of the crushing structure (5) and the spray plate base (1), and the crushing structure (5) is capable of heating the mixed gas.

6. The atomizing spray disc according to claim 1, characterized in that: The spray disc base (1) comprises a spray disc upper part (101), a spray disc middle part (102) and a spray disc lower part (103); the spray disc upper part (101) and the spray disc middle part (102) are detachably connected, and the spray disc upper part (101) and the spray disc middle part (102) surround the first nozzle (3); the spray disc lower part (103) and the spray disc middle part (102) are detachably connected, and the spray disc lower part (103) and the spray disc middle part (102) surround the second nozzle (4).

7. The atomizing spray disc according to claim 6, characterized in that: The crushing structure (5) is detachably embedded in the flow channel of the first nozzle (3).

8. The atomizing spray disc according to claim 6, characterized in that: The spray plate middle piece (102) comprises a middle piece upper piece (1021), a middle piece lower piece (1022), and a replaceable gasket (1023) sandwiched between the middle piece upper piece (1021) and the middle piece lower piece (1022).

9. An atomizing spray disc, comprising a spray disc base (1), wherein a through hole (2) is provided at the center of the spray disc base (1), and the through hole (2) is used for allowing metal melt to pass through; characterized in that: The spray plate base (1) is provided with a first nozzle (3) and a second nozzle (4), wherein the first nozzle (3) is located on the upper side of the second nozzle (4); the first nozzle (3) is used to spray a mixed gas formed by mixing nanoparticles and atomizing gas to break up the metal melt to form nanoparticle composite metal liquid masses; the second nozzle (4) is used to spray atomizing gas to further break up and atomize the nanoparticle composite metal liquid masses; a breaking structure (5) is provided in the flow channel of the first nozzle (3), wherein the breaking structure (5) is used to break up nanoparticle agglomerates in the mixed gas and further mix the mixed gas; The crushing structure (5) comprises a crushing body having a plurality of irregular microchannels inside, wherein the microchannels are connected to the upstream and downstream end surfaces of the crushing body; The diameter of the smallest circumscribed circle of any cross section of the microchannel is no greater than 0.5 mm.

10. The atomizing spray disc according to claim 9, characterized in that: The flow channel of the first nozzle (3) comprises an inlet section (301), a mixing section (302) and an outlet section (303) arranged in sequence along the air flow direction, and the crushing structure (5) is arranged in the mixing section (302).

11. The atomizing spray disc according to claim 10, characterized in that: The flow channel of the first nozzle (3) is a contraction-type flow channel, and the length of the outlet section (303) along the airflow direction is no more than 5 mm.

12. The atomizing spray disc according to any one of claims 9 to 11, characterized in that: An insulating heat-insulating layer (8) is provided between the upper and lower sides of the crushing structure (5) and the spray plate base (1), and the crushing structure (5) is capable of heating the mixed gas.

13. The atomizing spray disc according to claim 9, characterized in that: The spray disc base (1) comprises a spray disc upper part (101), a spray disc middle part (102) and a spray disc lower part (103); the spray disc upper part (101) and the spray disc middle part (102) are detachably connected, and the spray disc upper part (101) and the spray disc middle part (102) surround the first nozzle (3); the spray disc lower part (103) and the spray disc middle part (102) are detachably connected, and the spray disc lower part (103) and the spray disc middle part (102) surround the second nozzle (4).

14. The atomizing spray disc according to claim 13, characterized in that: The crushing structure (5) is detachably embedded in the flow channel of the first nozzle (3).

15. The atomizing spray disc according to claim 13, characterized in that: The spray plate middle piece (102) comprises a middle piece upper piece (1021), a middle piece lower piece (1022), and a replaceable gasket (1023) sandwiched between the middle piece upper piece (1021) and the middle piece lower piece (1022).

16. An atomizing spray disc, comprising a spray disc base (1), wherein a through hole (2) is provided at the center of the spray disc base (1), and the through hole (2) is used for allowing metal melt to pass through; characterized in that: The spray plate base (1) is provided with a first nozzle (3) and a second nozzle (4), wherein the first nozzle (3) is located on the upper side of the second nozzle (4); the first nozzle (3) is used to spray a mixed gas formed by mixing nanoparticles and atomizing gas to break up the metal melt to form nanoparticle composite metal liquid masses; the second nozzle (4) is used to spray atomizing gas to further break up and atomize the nanoparticle composite metal liquid masses; a breaking structure (5) is provided in the flow channel of the first nozzle (3), wherein the breaking structure (5) is used to break up nanoparticle agglomerates in the mixed gas and further mix the mixed gas; The crushing structure (5) comprises an upper base (501), a lower base (502), a plurality of upper rib needles (503) arranged on the lower surface of the upper base (501), and a plurality of lower rib needles (504) arranged on the upper surface of the lower base (502), the upper base (501) being arranged on the upper wall of the flow channel of the first nozzle (3), the lower base (502) being arranged on the lower wall of the flow channel of the first nozzle (3), and the upper rib needles (503) and the lower rib needles (504) being staggered with each other; The lengths of the upper rib needle (503) and the lower rib needle (504) are both 1 / 2 to 3 / 4 of the height of the flow channel at the local position of the flow channel where the upper rib needle (503) and the lower rib needle (504) are located.

17. The atomizing spray disc according to claim 16, characterized in that: The flow channel of the first nozzle (3) comprises an inlet section (301), a mixing section (302) and an outlet section (303) arranged in sequence along the air flow direction, and the crushing structure (5) is arranged in the mixing section (302).

18. The atomizing spray disc according to claim 17, characterized in that: The flow channel of the first nozzle (3) is a contraction-type flow channel, and the length of the outlet section (303) along the airflow direction is no more than 5 mm.

19. The atomizing spray disc according to claim 16, characterized in that: The upper substrate (501) is capable of applying ultrasonic excitation to the upper rib needle (503).

20. The atomizing spray disc according to claim 16, characterized in that: The spray disc base (1) comprises a spray disc upper part (101), a spray disc middle part (102) and a spray disc lower part (103); the spray disc upper part (101) and the spray disc middle part (102) are detachably connected, and the spray disc upper part (101) and the spray disc middle part (102) surround the first nozzle (3); the spray disc lower part (103) and the spray disc middle part (102) are detachably connected, and the spray disc lower part (103) and the spray disc middle part (102) surround the second nozzle (4).

21. The atomizing spray disc according to claim 20, characterized in that: The crushing structure (5) is detachably embedded in the flow channel of the first nozzle (3).

22. The atomizing spray disc according to claim 20, characterized in that: The spray plate middle piece (102) comprises a middle piece upper piece (1021), a middle piece lower piece (1022), and a replaceable gasket (1023) sandwiched between the middle piece upper piece (1021) and the middle piece lower piece (1022).

23. A nanoparticle-reinforced composite metal powder gas atomization device, comprising a smelting chamber (200), and an atomization chamber (300) arranged at the lower side of the smelting chamber (200), wherein a smelting crucible (400) and a tundish (500) are arranged in the smelting chamber (200), a guide nozzle (600) is connected to the lower end of the tundish (500), and the guide nozzle (600) extends into the atomization chamber (300), the smelting crucible (400) is used to smelt a metal substrate to obtain a metal melt, and the tundish (500) is used to receive the metal melt obtained by the smelting crucible (400); characterized in that: The atomizing spray disc (100) according to any one of claims 1 to 22 is arranged in the atomizing chamber (300), and the guide nozzle (600) extends into the upper part of the through hole (2) of the atomizing spray disc (100) or is arranged above the atomizing spray disc (100) and directly facing the through hole (2); The nanoparticle-reinforced composite metal powder gas atomization device further comprises a nanoparticle adder (700), wherein the nanoparticle adder (700) is used to deliver the mixed gas to the atomizing spray disc (100).

24. The nanoparticle-reinforced composite metal powder gas atomization device according to claim 23, characterized in that: The nanoparticle additive (700) comprises a storage tank (71), a feeder (72), a carrier gas generator (73) and a mixer (74); the storage tank (71) is connected to the mixer (74) via the feeder (72); the carrier gas generator (73) and the atomizing spray disc (100) are both connected to the mixer (74); the storage tank (71) is used to store the nanoparticles; the carrier gas generator (73) is used to deliver the atomizing gas to the mixer (74); the feeder (72) is used to deliver the nanoparticles in the storage tank (71) into the mixer (74); the mixer (74) is used to mix the nanoparticles and the atomizing gas to form the mixed gas and deliver it to the atomizing spray disc (100).

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