Method of manufacturing object comprising beryllium

Abstract

A method of making an object comprising beryllium by depositing a layer of beryllium and a metal inoculant is disclosed. The grain refinement enables the beryllium article to have beneficial properties in terms of strength and durability.

Description

Priority declaration

[0001] This application claims priority to U.S. Provisional Application No. 63 / 409,102, filed on September 22, 2022, which is incorporated herein by reference in its entirety. Technical Field

[0002] The present disclosure relates to a method of producing an object comprising beryllium. In particular, the method involves depositing successive layers that are solidified to form a continuous beryllium matrix having an equiaxed grain crystal structure. background

[0003] Beryllium is a metal with very desirable properties. These include high stiffness (Young's modulus = 287 GPa), low density (1.85 g / cc), high elastic modulus (130 GPa), high specific heat (1925 J / kg·K), high thermal conductivity (216 W / m·K), and low linear thermal expansion coefficient (11.4×10 6 / °K). Therefore, beryllium and its composites can be used in aviation and aerospace structures, high-performance engines and brakes, and electronic components to provide thermal performance and vibration damping. Beryllium and its composites can also be used in a variety of different applications, including combustion applications, hypersonic vehicles, computer components, optical devices for space-based and land-based systems, satellite structures, solar collectors, and nuclear energy growth applications.

[0004] One limitation is that casting methods are not suitable for making beryllium products and result in columnar solidification. Beryllium is a highly reactive metal with a high melting point, making it easy to react with the mold wall material to form beryllium compounds (BeO, etc.) trapped in the solidified metal. In addition, the grain size is greater than 500 microns, and is generally much higher, up to 50,000 microns. This is too large to meet strength requirements and results in brittle materials. Further attempts to refine the grains by mechanical processing have not yet achieved commercial success. In order to overcome the beryllium production problem, beryllium powder has been used. Beryllium powder can be formed by ball milling, disc grinding or gas atomization processes. The powder is consolidated into an ingot, which can be further processed into a molded component of beryllium. This method requires careful handling of beryllium powder. In addition, the powder process has a low material utilization rate, which results in low efficiency and increased costs. The powder process is also limited in its ability to form complex shapes.

[0005] Objects built by depositing layers can allow for complex shapes, but still suffer from poor crystal structure due to the lack of plastic deformation from mechanical forming. Since the layers are built in one direction, solidification tends to result in poor microstructure, and columnar grains are prevalent. The undesirable reduction in mechanical properties results in a loss of strength and durability.

[0006] There remains a need to eliminate columnar solidification in order to produce beryllium articles having reduced grain size in an efficient manner. Overview

[0007] The present disclosure relates to a method for manufacturing beryllium articles by reducing or more preferably eliminating columnar structures. The microstructure of the beryllium article is improved by adding an inoculant, thereby improving the mechanical properties. In one embodiment, the method disclosed herein provides for forming molten beryllium into a layer comprising a continuous beryllium matrix having a crystalline structure of equiaxed grains. An increase in equiaxed grains is preferred to obtain a more consistent microstructure. The grain refinement achieved by the disclosed embodiments also enables the production of complex objects made of beryllium having an average grain size of 1 to 80 microns, preferably an average grain size of 5 to 40 microns.

[0008] In one aspect, a method of making an object comprising beryllium is provided, the method comprising preparing a mixture of beryllium powder and at least one metal inoculant; depositing a layer comprising the mixture on a surface; applying energy to at least a portion of the layer in a reducing atmosphere to form molten beryllium; solidifying the molten beryllium into a layer comprising a continuous beryllium matrix having an equiaxed grain crystal structure; and repeating the deposition / application / solidification for subsequent layers until an object having a geometric shape is obtained. In one embodiment, at least a portion of the metal inoculant is bonded to the surface of the beryllium powder. The metal inoculant may include at least one metal inoculant comprising Be 2 Co、Be 2 Nb、Be 2 She, Be 2 Ti、Be 2 W. Be 5 Hf、Be 5 Sc、Be 5 Zr、Be 7 Cu 13 、BeFe 3 , Cu 3 Mo, Cu 9 W, Mo, Nb, RbO 2 , ReRh, Ta, TiV or W. Preferred metal inoculants may include Be 2 Co、Be 2 Nb、Be 2 She, Be 2 Ti、Be 2 W. Be5 Hf、Be 5 Sc or Be 5 Zr. The mixture, which may be prepared by blending, atomization, mechanical alloying, or resonance mixing, comprises 90 to 99.99 wt % beryllium and 0.01 to 10 wt % of the at least one metal inoculant. The beryllium powder may have a D50 average particle size of 10 to 50 microns. The metal inoculant may have a D50 average particle size of 0.001 to 5 microns. In one embodiment, energy is applied to at least a portion of the layer using an electron beam or a laser.

[0009] In one aspect, a method of grain refining an object containing beryllium is provided, the method comprising combining beryllium and a selected from Be 2 Co、Be 2 Nb、Be 2 She, Be 2 Ti、Be 2 W. Be 5 Hf、Be 5 Sc、Be 5 Zr、Be 7 Cu 13 、BeFe 3 , Cu 3 Mo, Cu 9 W, Mo, Nb, RbO 2 , ReRh, Ta, TiV and W to form a pre-alloyed composition; depositing a layer comprising the pre-alloyed composition on a surface; cycling at least a portion of the layer by applying energy to form molten beryllium; solidifying the molten beryllium; and repeating the deposition / cycling / precipitation for subsequent layers, wherein each subsequent layer comprises the pre-alloyed composition and has an average grain size of 1 to 80 microns. Preferred metal inoculants may include Be 2 Co、Be 2 Nb、Be 2 She, Be 2 Ti、Be 2 W. Be 5 Hf、Be 5 Sc or Be 5 Zr. The pre-alloy composition comprises 90 to 99.99 weight percent beryllium and 0.01 to 10 weight percent of the at least one metallic inoculant.

[0010] In another aspect, an article is provided, comprising beryllium, wherein the beryllium is an equiaxed grain crystal structure comprising beryllium; and 2 Co、Be 2 Nb、Be 2 She, Be2 Ti、Be 2 W. Be 5 Hf、Be 5 Sc、Be 5 Zr、Be 7 Cu 13 、BeFe 3 , Cu 3 Mo, Cu 9 W, Mo, Nb, RbO 2 At least one metal inoculant of ReRh, Ta, TiV and W to form grains 1:1 or 2:1 lattice matched with the beryllium grains; wherein the equiaxed grains of beryllium have an average grain size of 1 to 80 microns. The crystal structure may contain 50 volume % to 100 volume % equiaxed grains. Preferred metal inoculants may include Be 2 Co、Be 2 Nb、Be 2 She, Be 2 Ti、Be 2 W. Be 5 Hf、Be 5 Sc or Be 5 Zr.

[0011] These and other non-limiting features are more particularly described below. Details

[0012] The present disclosure may be understood more readily by reference to the following detailed description of contemplated embodiments and the examples included therein.In the following specification and in the claims that follow, reference will be made to a number of terms which shall be defined to have the following meanings.

[0013] Unless otherwise defined, all technical and scientific terms used herein have the same meanings as are generally understood by those of ordinary skill in the art. In the event of a conflict, this document (including definitions) shall prevail. Preferred methods and materials are described below, although methods and materials similar or equivalent to those described herein may be used in the practice or testing of the present disclosure. All publications, patent applications, patents, and other references mentioned herein are incorporated herein by reference in their entirety. The materials, methods, and examples disclosed herein are exemplary only and are not intended to be limiting.

[0014] The singular forms "a," "an," and "the" include plural referents unless the context clearly dictates otherwise.

[0015] The term "comprising" as used in the specification and claims may include the embodiments of "consisting of" and "consisting essentially of." As used herein, the terms "comprising," "including," "having," "having," "may," "containing," and variations thereof are intended to be open transition phrases that require the presence of specified ingredients / steps and allow for the presence of other ingredients / steps. However, such descriptions should be interpreted as also involving describing compositions or methods as "consisting of" and "consisting essentially of" the listed ingredients / steps, which only allow for the presence of the specified ingredients / steps, and any impurities that may result therefrom, and exclude other ingredients / steps.

[0016] The numerical values ​​in the specification and claims of this application, when they refer to mixtures, pre-alloyed compositions or objects, reflect average values ​​for compositions that may contain individual polymers of different properties. The numerical values ​​disclosed herein should be understood to include the same value when reduced to the same number of significant figures and values ​​that differ from the specified value by less than the experimental error of the type of conventional measurement techniques described in this application for determining the value.

[0017] All ranges disclosed herein are inclusive of the recited endpoints and are independently combinable (e.g., the range "1 micron to 80 microns" includes the endpoints 1 micron and 80 microns, and all intermediate values). The endpoints of the ranges and any values ​​disclosed herein are not limited to the exact ranges or values; they are imprecise enough to include values ​​approximating these ranges and / or values.

[0018] As used herein, approximations can be used to modify any quantitative representation that may vary without causing a change in the basic function to which it relates. Therefore, values ​​modified by terms such as "approximately" and "substantially" may not be limited to the specified exact value in some cases. The modifier "approximately" should also be considered to disclose a range defined by the absolute values ​​of the two endpoints. For example, the expression "about 2 to about 4" also discloses a range of "2 to 4". The term "approximately" can refer to plus or minus 10% of the numerical value shown. For example, "about 10%" can refer to a range of 9% to 11%, and "about 1" can refer to 0.9-1.1.

[0019] For the enumeration of numerical ranges herein, each intermediate number with the same precision is explicitly considered. For example, for the range of 6-9, in addition to 6 and 9, the numbers 7 and 8 are also considered, and for the range of 6.0-7.0, the numbers 6.0, 6.1, 6.2, 6.3, 6.4, 6.5, 6.6, 6.7, 6.8, 6.9 and 7.0 are explicitly considered.

[0020] As described herein, there is a method for producing a beryllium product. Beryllium powder and a metal inoculant are used to form a continuous beryllium matrix with an equiaxed grain crystal structure. First, a mixture of beryllium (preferably beryllium powder) and a metal inoculant is prepared. In some embodiments, the mixture may be referred to as a pre-alloy composition. The mixture may evenly distribute the metal inoculant in the beryllium powder. The mixture of the beryllium powder and the metal inoculant is exposed to an energy source and solidified by heating and cooling in a cycle to produce a continuous beryllium matrix with an equiaxed grain crystal structure. It has been found that the added metal inoculant acts as a nucleation site for forming a fine grain structure during solidification. These steps may be repeated until an object with a geometric or three-dimensional shape is obtained. In one embodiment, a mixture of beryllium (preferably beryllium powder) and a metal inoculant may be cycled through heating and cooling so that each layer has a continuous beryllium matrix with an equiaxed grain crystal structure. In one embodiment, after the heating / cooling cycle, the grain structure of the beryllium product may have equiaxed grains.

[0021] Without being bound by theory, the presence of equiaxed grains has been shown to contribute to grain refinement of the beryllium article. Grain refinement of the beryllium article can result in improved strength and processing when forming an article having a series of layers. In one embodiment, the beryllium article may have an average grain size of 1 to 80 microns, such as 1 to 75 microns, 1 to 60 microns, 1 to 50 microns, 1 to 40 microns, 5 to 40 microns, 5 to 25 microns, 5 to 15 microns, or 10 to 15 microns. In one embodiment, a portion of the grains of the beryllium article may have an aspect ratio of less than 3:1. In particular, 75% of the grains of the beryllium article may have an aspect ratio of less than 3:1, such as less than 2.5:1 or less than 2:1. The average grain size and aspect ratio can be determined using optical imaging, such as SEM imaging, and by using the comparative, planimetric, or intercept parameters of ASTM E 112-12.

[0022] The resulting grain structure of the body comprising beryllium has a significantly reduced average grain size compared to processes that do not include the disclosed metal inoculant.

[0023] The beryllium matrix comprises beryllium crystals forming grains, each grain having its own unique orientation (distinctorientation). The grains are connected together via grain boundaries (grain boundaries) formed during the cyclic process of applying energy and solidification. Grain boundaries can affect mechanical properties. Due to the metal inoculant that forms many grain refinement sites, the crystal structure comprises equiaxed grains. In one embodiment, the object comprising beryllium has a continuous beryllium matrix with an equiaxed grain crystal structure. The equiaxed grains are roughly similar in length, width and height. In one embodiment, the crystal structure comprises more than 50% by volume of equiaxed grains, such as more than 75% by volume of equiaxed grains, or more than 90% by volume of equiaxed grains. In terms of range, the crystal structure may comprise 50% to 100% by volume of equiaxed grains, such as 75% to 100% by volume or 90% to 100% by volume. Increasing the amount of equiaxed grains reduces the amount of columnar grains. Microscopic techniques such as x-ray diffraction analysis can be used to quantify the grains.

[0024] In one embodiment, the metal inoculant combined with beryllium includes a metal that forms a 1:1 or 2:1 interface with the edge of the beryllium grain. In one embodiment, at least a portion of the metal inoculant is bonded to the surface of the beryllium powder. This can allow the metal inoculant to be distributed throughout the beryllium matrix. The metal inoculant can be present as a loose powder, paste, or suspension that can be combined with beryllium. In one embodiment, the metal inoculant remains unreacted when it is bonded to the surface of the beryllium powder. There are several methods to combine the metal inoculant and beryllium, such as mixing, blending, atomizing, mechanical alloying, resonant mixing, or a combination thereof. When the beryllium powder and the metal inoculant have different sizes, resonant mixing is useful in order to achieve adequate mixing. In one embodiment, resonant mixing induces non-contact acoustic mixing with sound waves having a frequency of 20 to 80 Hz to achieve good mixing in a short time without causing rupture or stress to the beryllium and the metal inoculant. Accordingly, a metal inoculant can be combined with beryllium, and in some embodiments, a mixture of metal inoculants can be present.

[0025] In one embodiment, the metal inoculant may comprise Be 2 Co、Be 2 Nb、Be 2 She, Be 2 Ti、Be 2 W. Be 5 Hf、Be 5 Sc、Be 5 Zr、Be 7 Cu 13 、BeFe 3 , Cu 3 Mo, Cu 9 W, Mo, Nb, RbO2 , ReRh, Ta, TiV or W. In one embodiment, a combination of metal inoculants may be used. More preferably, the metal inoculant may include Be 2 Co、Be 2 Nb、Be 2 She, Be 2 Ti、Be 2 W. Be 5 Hf、Be 5 Sc or Be 5 Zr. In particular, metal inoculants introduce grain refinement and provide an equiaxed grain crystal structure. These metal inoculants can effectively match beryllium in terms of interatomic spacing misfit and interplanar spacing misfit. Crystal orientation can be measured by polarized optical microscopy and / or EBSD (electron backscatter diffraction).

[0026] In one embodiment, the mixture preparation step may be optional, and the beryllium and metal inoculant may be deposited as a layer without forming a mixture. Accordingly, a method of producing a beryllium article is provided, comprising depositing a layer comprising beryllium and a metal inoculant on a surface, heating at least a portion of the layer by applying energy to form molten beryllium, solidifying the molten beryllium, and repeating the deposition / cycle / precipitation for subsequent layers. After building the desired layers, the object may be formed, wherein the beryllium-based article has an average grain size of 1 to 80 microns.

[0027] In one embodiment, the metal inoculant may be a metal powder. The metal powder may have an aspect ratio (average length to average width) of 1:1 to 100:1, such as 1:1 to 50:1, 1:1 to 20:1, 1:1 to 10:1, or 1:1 to 5:1. The metal powder may be smaller than beryllium powder. The metal powder may have an average (D) of less than 10 microns, such as less than 8 microns, less than 5 microns, less than 2.5 microns, less than 2 microns, or less than 1 micron. 50 ) particle size. In some embodiments, the metal powder may be nanoparticles; for example, may have an average (D) of less than 1 micron. 50 In some embodiments, the nanoparticles may have an average (D) of 10 to 1000 nanometers, such as 25 to 950 nanometers, 50 to 900 nanometers, 100 to 800 nanometers, or 300 to 700 nanometers. 50 Thus, the metal powder may have an average (D) of 0.0001 to 10 microns, such as 0.0005 to 7.5 microns, 0.001 to 5 microns, 0.01 to 2.5 microns, or 0.1 to 1.5 microns. 50 ) particle size. The particle size is D 50, or the diameter at which a particle accumulation percentage of 50 volume % is reached.

[0028] In one embodiment, each deposited layer may contain beryllium in an amount of 90 to 99.99 wt % based on the total weight of each layer. More preferably, each layer may contain beryllium in an amount of 95 to 99.9 wt %, such as 97 to 99.5 wt % or 98 to 99 wt %.

[0029] In one embodiment, the beryllium comprises beryllium powder. Exemplary beryllium powders include S-65 grade (99.2% minimum Be content, 0.9% maximum BeO), S-200 grade (98.5% minimum Be content), 0-30 (Hot Isostatically Pressed beryllium, minimum 99% Be content, 0.5% maximum BeO), and are all available from Materion Corporation. The beryllium powder may have an aspect ratio (average length to average width) of 1:1 to 100:1, e.g., 1:1 to 50:1, 1:1 to 20:1, 1:1 to 10:1, or 1:1 to 5:1. In one embodiment, the beryllium powder may be spherical. The beryllium powder may have an average (D) of 1 micron to 200 microns, such as 5 microns to 175 microns, 10 microns to 150 microns, 15 microns to 100 microns, 25 microns to 70 microns, or 25 microns to 50 microns. 50 ) particle size. The particle size is D 50 , or the diameter at which a cumulative percentage of particles of 50% by volume is reached. Powders less than 200 microns can be constructively used to form beryllium products with reduced grain refinement. When necessary, the beryllium powder can be screened to achieve the desired size.

[0030] In one embodiment, the beryllium powder can be in the form of particles with a core-shell structure, wherein the beryllium constitutes the core and the continuous or semi-continuous coating constitutes the shell. In some embodiments, the continuous or semi-continuous coating may include a metal inoculant. The coating of beryllium can be achieved by ball milling, resonance mixing, spray binding, spray drying, laser ablation, electrical-discharge machining, and atomic layer deposition. In some embodiments, the coating includes nickel in the form of pure nickel or a nickel alloy. The core can be 0.1% to 99.9% by weight of the particle, or 50% to 99.9% by weight, or about 92% to less than 100% by weight of the particle. In some embodiments, the coating can be 0.1% to 99.9% by weight of the particle, or 0.1% to 50% by weight, or greater than 0% to about 8% by weight of nickel. In a particular embodiment, the beryllium powder includes from about 92 wt% to less than 100 wt% beryllium and from greater than 0 wt% to about 8 wt% nickel. Generally, the coating is believed to form particles for grain refinement.

[0031] The metal inoculant may be combined with beryllium in an effective amount to increase the number of grains during solidification. In one embodiment, the metal inoculant may be present in an amount of 0.01 to 10 wt %, based on the total weight of each layer. More preferably, the metal inoculant may be present in an amount of 0.1 to 5 wt %, such as 0.5 to 3 wt %, or 1 to 2 wt %.

[0032] By cycling several deposition layers, an object comprising a beryllium product can be formed. In particular, the method can achieve a three-dimensional beryllium product. In the method, the cycle may involve applying energy to at least a portion of the layer to form molten beryllium, and solidifying the molten beryllium into layers by cooling. After cycling at a temperature higher than that at which the molten beryllium is formed, the molten beryllium is solidified. The formation of an equiaxed grain crystal structure is provided to achieve the desired grain refinement. The equiaxed grain crystal structure can also reduce or eliminate columnar grain growth. In one embodiment, a complex shape can be formed by a product having multiple layers. In one embodiment, the resulting shape can be a geometric shape or a three-dimensional shape formed by multiple layers. In one embodiment, the method deposits an initial layer, preferably at a relatively high rate. In one embodiment, the initial layer can be uniformly deposited by depositing the mixture on the surface of a substrate. In some embodiments, the initial layer can be deposited on a surface such as a substrate, a platform or a substrate.

[0033] The method may begin by depositing an initial layer in a build box. Preferably, a mixture comprising beryllium powder and a metal inoculant is transferred to the build box with minimal loss or contamination of the surrounding area. The build box comprises a surface, such as a build platform, and sidewalls. The build platform is typically a flat surface on which subsequent layers are deposited. The build platform may be moved along a vertical z-axis based on signals provided by a computer-operated controller. The sidewalls cooperate with the build platform to form a "box" containing the deposited mixture. Typically, the sidewalls remain in a fixed position and the build platform moves downward to allow the next layer of the mixture to be deposited.

[0034] Each layer can be deposited on the surface with a predetermined pattern. In some embodiments, the layer based on the computer-aided design (CAD) model determines the preset pattern. Any suitable technology for depositing the initial layer is applicable to the method, including spreading, coating, brushing, roller coating, spraying or dispensing. In one embodiment, one or more deposition heads are used and moved in the horizontal xy plane. A controller can be used to move the one or more deposition heads specified by the design. The horizontal xy plane is a plane limited by an x-axis and a y-axis, wherein the x-axis, the y-axis and the z-axis are orthogonal to each other.

[0035] In some embodiments, the deposition is performed under an inert gas atmosphere. In one embodiment, the deposition can be performed in a reducing atmosphere to reduce the formation of oxides. After depositing the layers of beryllium and metal inoculants, energy can be applied in a reducing atmosphere. In one embodiment, the reducing atmosphere contains less than 20% by volume of oxygen or other oxidants, such as less than 15% by volume, less than 10% by volume, or less than 5% by volume.

[0036] In one embodiment, each layer can be deposited in a uniform manner. The initial layer can have a thickness of 20 to 200 microns, for example 25 to 150 microns, 25 to 110 microns, 30 to 100 microns, 35 to 75 microns or 40 to 60 microns. In some embodiments, the layer can be formed by compacting the deposited material with an optional compacting method. It may be necessary to use a mechanical compactor such as a scraper or double rolling or electrostatic force to compact the powder to provide a thin layer. In some embodiments, these layers can be deposited.

[0037] After depositing the initial layer, the method applies energy (preferably from an electron beam or laser) to at least a portion of the layer using a cyclic process to form molten beryllium, and then solidifies the molten beryllium into a layer. In one embodiment, the method involves solidifying the molten beryllium into a layer comprising a continuous beryllium matrix having an equiaxed grain crystal structure. The cycle is transformed at a high rate through a thermal gradient to form molten beryllium. In one embodiment, an energy source can be directed to at least a portion of the initial layer. The energy source can generate localized or focused energy to heat at least a portion of the initial layer, preferably to heat at least a portion of the initial layer. In one embodiment, the energy source can be sufficient to form molten beryllium. The energy source can be a 10 3 W / mm 2 Up to 10 7 W / mm 2 , for example 10 4 W / mm 2 Up to 10 7 W / mm 2 , or 10 5 W / mm 2 Up to 10 6 W / mm 2 The power density of the electron beam or laser beam is less than 10 7 W / mm 2 The power of the energy source is sufficient to form molten beryllium. In one embodiment, the effective diameter of the energy source can be 10 to 200 microns, such as 25 to 150 microns, or 35 to 100 microns. The scanning speed of the energy source can be 10mm / s to 2000mm / s, such as 50 to 1500mm / s or 100 to 1000mm / s. The raster width of the energy source can be 50 to 500 microns, such as 75 to 450 microns, 75 to 400 microns, or 100 to 350 microns. In one embodiment, the layer thickness can be 20 microns to 200 microns, such as 25 microns to 175 microns or 50 microns to 150 microns.

[0038] In one embodiment, the energy source and / or another source heats the initial layer to a temperature of 1000° C. to 1600° C., e.g., 1100° C. to 1450° C., 1200° C. to 1400° C., or 1290° C. to 1325° C. In one embodiment, the applied energy is applied for a duration of less than 300 seconds, e.g., less than 240 seconds, less than 180 seconds, less than 120 seconds, less than 90 seconds, less than 60 seconds, less than 50 seconds, less than 45 seconds, less than 30 seconds, less than 25 seconds, less than 20 seconds, less than 10 seconds, less than 5 seconds, less than 1 second, or less than 0.5 seconds. In terms of ranges, in one embodiment, energy is applied for a time of 0.01 to 300 seconds, e.g., 0.01 to 240 seconds, 0.1 to 180 seconds, 0.2 to 120 seconds, 0.2 to 90 seconds, 0.25 to 60 seconds, 0.5 to 60 seconds, 0.5 to 30 seconds, 0.5 to 15 seconds, or 0.5 to 10 seconds.

[0039] Unless preheating is used, the initial layer can be deposited at room temperature (20 to 25° C.). In some embodiments, the deposited initial layer can be preheated in the build box to a temperature of at least 100° C., such as at least 120° C., or 150° C., at least 200° C., at least 400° C., at least 450° C., or at least 500° C.

[0040] The thermal condition of the article can be monitored using an infrared temperature sensor, a thermocouple, a resistance temperature detector, a thermistor, or other suitable temperature sensor. The sensor can monitor the temperature in the area where the energy and / or coolant is applied. In response to the temperature, the method can adjust the cooling rate by adjusting the flow rate, duration, or temperature of the coolant.

[0041] Operating the method at reduced atmospheric pressure or under vacuum can provide quality control for the layer and beryllium article material. Nevertheless, in some embodiments, the method can be operated at atmospheric pressure.

[0042] As part of the cyclic process, the method also cools the deposited layer. In one embodiment, the minimum cooling rate may be greater than 10°C / min, such as greater than 15°C / min or greater than 20°C / min. In some embodiments, the cooling rate may be greater than 1000°C / min, such as greater than 10,000°C / min, to achieve solidification. Cooling or supercooling can be achieved at a cooling rate of 10°C / min to 10,000°C / min, such as 20°C / min to 5,000°C / min, 50°C / min to 3,000°C / min, or 100°C / min to 1000°C / min. In one embodiment, the cooling can be in the building direction of the layer. During the solidification process, the molten beryllium is formed into a continuous beryllium matrix having an equiaxed grain crystal structure. In one embodiment, the crystal structure is not only oriented in the building direction.

[0043] In one embodiment, cooling or undercooling for solidification may be reduced due to lattice matching and low interfacial energy of the metal inoculant and the continuous beryllium matrix. Stress reduction may be improved during solidification of the layers to produce the object comprising beryllium.

[0044] A coolant may be used to achieve the desired cooling. The coolant may further reduce the temperature gradient in the layer that tends to provide columnar grain formation and thereby improve grain refinement. In one embodiment, the coolant may be an inert gas, such as nitrogen or a noble gas, particularly argon. The coolant may be a mixture of gases. The coolant may be delivered to the layer as a focused gas stream at a temperature of less than or equal to 100°C, such as less than or equal to 75°C, less than or equal to 50°C, less than or equal to 25°C, less than or equal to 0°C, less than or equal to -10°C, less than or equal to -25°C or less than or equal to -50°C. In terms of range, the coolant may be applied at a temperature of -200°C to 100°C, such as -150°C to 50°C or -100°C to 25°C, including sub-ranges therein. The flow rate of the coolant may be adjusted when the layer is deposited, and the flow rate may be less than 500L / min, such as less than 250L / min or less than 100L / min.

[0045] The method can continue in a similar manner for subsequent layers, thereby cycling each deposited mixture layer and forming a continuous beryllium matrix layer having an equiaxed grain crystal structure. After allowing sufficient time for precipitation, one or more subsequent layers can be deposited in a predetermined pattern on at least a portion of the initial layer opposite the surface. This continues to build a beryllium product, wherein each subsequent layer is deposited on at least a portion of the previously deposited layer. In one embodiment, subsequent layers are deposited to achieve complex shapes, such as three-dimensional shapes. Subsequent layers can be deposited at room temperature, or can be preheated similarly to the initial layer. In a similar manner, an energy source is directed to at least a portion of the subsequent layer to circulate at a temperature higher than that at which molten beryllium is formed. In one embodiment, the energy source is controlled within operating parameters similar to those of the initial layer. Depending on the product, the pattern of each subsequent layer can be different. In some embodiments, subsequent layers can be deposited on at least a portion of the previous layer or the initial layer.

[0046] In some embodiments, the surface or build plate can be lowered by the thickness of the next subsequent layer. The thickness of the subsequent layer may vary, and in one embodiment, the subsequent layer may have a thickness of 20 to 200 microns, such as 25 to 150 microns, 25 to 110 microns, 30 to 100 microns, 35 to 75 microns, or 40 to 60 microns. In some embodiments, each subsequent layer may have a similar thickness, or the thickness may be adapted to the beryllium product. The method may continue to repeat deposition, circulation, and precipitation until the desired beryllium product is formed. In one embodiment, a three-dimensional object is formed. In one embodiment, the beryllium product may be formed by one or more subsequent layers, such as at least 5 subsequent layers, at least 10 subsequent layers, or at least 20 subsequent layers. For some products, hundreds of layers may be used, so the number of layers is not limited.

[0047] Each subsequent layer may include a metal inoculant, and the method may repeat the deposition / application / solidification steps for each layer.

[0048] The orientation of the microstructure is not limited to the build direction of subsequent layers. The microstructure of the beryllium-containing object may contain multiple dendrite layers with different primary growth direction angles relative to each other. This provides a crack-free beryllium-containing object having a complex shape that can be produced in an efficient manner in terms of cost, material and time. The presence of a metal inoculant further improves the crack-free nature of the object.

[0049] In some embodiments, the method further includes solidifying the multiple layers before sintering the preform. In one embodiment, the beryllium product can be solutionized and then quenched. The beryllium product can be annealed for 6 to 12 hours, for example, 8 to 10 hours. The quenching rate can be greater than 25°C / min, for example, greater than 50°C / min or greater than 100°C / min. Quenching can be carried out slowly at room temperature. The annealed product can be finished, for example, by polishing or electroplating. The surface roughness of the product can be reduced, for example, by bead blasting or barrel finishing. In some embodiments, the beryllium product made may have scattered or unfused particles in one or more layers. Unfused particles can be removed by blowing or vacuuming as needed.

[0050] The present disclosure has been described with reference to exemplary embodiments. Obviously, after reading and understanding the foregoing detailed description, others will think of modifications and variations. The present disclosure is intended to be interpreted as including all such modifications and variations as long as they fall within the scope of the appended claims or their equivalents.

[0051] As used hereinafter, any reference to a series of embodiments is understood to be a reference to each of those embodiments individually (eg "embodiments 1-4" is understood to be "embodiment 1, 2, 3 or 4").

[0052] Embodiment 1 is a method of manufacturing an object comprising beryllium, the method comprising preparing a mixture of beryllium powder and at least one metal inoculant; depositing a layer comprising the mixture on a surface; applying energy to at least a portion of the layer in a reducing atmosphere to form molten beryllium; solidifying the molten beryllium into a layer comprising a continuous beryllium matrix having an equiaxed grain crystal structure; and repeating the deposition / application / solidification for subsequent layers until an object having a geometric shape is obtained.

[0053] Embodiment 2 is a version of embodiment 1, wherein at least a portion of the metal inoculant is bonded to a surface of the beryllium powder.

[0054] Embodiment 3 is an embodiment of any of embodiments 1 or 2, wherein the at least one metal inoculant comprises a metal selected from Be 2 Co、Be 2 Nb、Be 2 She, Be 2 Ti、Be 2 W. Be 5 Hf、Be 5 Sc、Be 5 Zr、Be 7 Cu 13、BeFe 3 , Cu 3 Mo, Cu 9 W, Mo, Nb, RbO 2 , ReRh, Ta, TiV and W.

[0055] Embodiment 4 is an embodiment of any one of embodiments 1 or 2, wherein the at least one metal inoculant comprises a metal selected from Be 2 Co、Be 2 Nb、Be 2 She, Be 2 Ti、Be 2 W. Be 5 Hf、Be 5 Sc and Be 5 At least one particle of Zr.

[0056] Embodiment 5 is the embodiment of any of embodiments 1-4, wherein the continuous beryllium matrix has an average grain size of 1 to 80 microns.

[0057] Embodiment 6 is the embodiment of any of embodiments 1-5, wherein the continuous beryllium matrix has an average grain size of 5 to 40 microns.

[0058] Embodiment 7 is the embodiment of any of embodiments 1-6, wherein the continuous beryllium matrix has an average grain size of 5 to 25 microns.

[0059] Embodiment 8 is the embodiment of any one of embodiments 1-7, wherein the mixture is prepared by blending, atomization, mechanical alloying, or resonance mixing.

[0060] Embodiment 9 is the embodiment of any of embodiments 1-8, wherein the mixture comprises 90 to 99.99 weight percent beryllium.

[0061] Embodiment 10 is the embodiment of any of embodiments 1-9, wherein the mixture comprises 0.01 to 10 weight percent of the at least one metal inoculant.

[0062] Embodiment 11 is the embodiment of any of embodiments 1-10, wherein energy is applied to at least a portion of the layer using an electron beam or a laser.

[0063] Embodiment 12 is an embodiment of any one of embodiments 1-11, wherein the reducing atmosphere has a volume concentration of oxygen or other oxidants of 10 vol% or less.

[0064] Embodiment 13 is the embodiment of any of embodiments 1-12, wherein the beryllium powder has a D50 average particle size of 10 to 50 microns.

[0065] Embodiment 14 is the embodiment of any of embodiments 1-13, wherein the at least one metal inoculant has a D50 average particle size of 0.001 to 5 microns.

[0066] Embodiment 15 is the embodiment of any of embodiments 1-14, wherein the object made by the method comprises beryllium, wherein the beryllium is a crystal structure comprising equiaxed grains of beryllium; and 2 Co、Be 2 Nb、Be 2 She, Be 2 Ti、Be 2 W. Be 5 Hf、Be 5 Sc、Be 5 Zr、Be 7 Cu 13 、BeFe 3 , Cu 3 Mo, Cu 9 W, Mo, Nb, RbO 2 At least one metal inoculant of ReRh, Ta, TiV and W is added to form grains that are 1:1 or 2:1 lattice matched with the beryllium grains.

[0067] Embodiment 16 is a method of grain refining an object comprising beryllium, the method comprising combining beryllium and a material selected from the group consisting of Be 2 Co、Be 2 Nb、Be 2 She, Be 2 Ti、Be 2 W. Be 5 Hf、Be 5 Sc、Be 5 Zr、Be 7 Cu 13 、BeFe 3 , Cu 3 Mo, Cu 9 W, Mo, Nb, RbO 2 , ReRh, Ta, TiV and W to form a pre-alloy composition; depositing a layer comprising the pre-alloy composition on a surface; circulating at least a portion of the layer by applying energy to form molten beryllium; solidifying the molten beryllium; and repeating the deposition / circulation / precipitation for subsequent layers, wherein each subsequent layer comprises the pre-alloy composition and has an average grain size of 1 to 80 microns.

[0068] Embodiment 17 is an embodiment of embodiment 16, wherein the pre-alloy composition comprises beryllium powder.

[0069] Embodiment 18 is the embodiment of any of embodiments 16 or 17, wherein the at least one metal inoculant comprises a metal selected from the group consisting of Be 2 Co、Be 2 Nb、Be 2 She, Be 2 Ti、Be 2 W. Be 5 Hf、Be 5 Sc and Be 5 At least one particle of Zr.

[0070] Embodiment 19 is the embodiment of any of embodiments 16-18, wherein the average grain size is 5 to 40 microns.

[0071] Embodiment 20 is the embodiment of any of embodiments 16-18, wherein the average grain size is 5 to 25 microns.

[0072] Embodiment 21 is an embodiment of any one of embodiments 16-20, wherein the pre-alloyed composition is prepared by blending, atomization, mechanical alloying, or resonance mixing.

[0073] Embodiment 22 is an embodiment of any of embodiments 16-21, wherein the pre-alloy composition comprises 90 to 99.99 weight percent beryllium.

[0074] Embodiment 23 is an embodiment of any of embodiments 16-22, wherein the pre-alloy composition comprises 0.01 to 10 weight percent of the metal inoculant.

[0075] Embodiment 24 is the embodiment of any one of embodiments 16-23, wherein energy is applied to at least a portion of the layer using an electron beam or a laser.

[0076] Embodiment 25 is an embodiment of any one of embodiments 16-24, wherein the reducing atmosphere has a volume concentration of oxygen or other oxidants of 10 volume % or less.

[0077] Embodiment 26 is the embodiment of any of embodiments 16-25, wherein the beryllium powder has a D50 average particle size of 10 to 50 microns.

[0078] Embodiment 27 is the embodiment of any of embodiments 16-26, wherein the at least one metal inoculant has a D50 average particle size of 0.001 to 5 microns.

[0079] Embodiment 28 is an object comprising beryllium, wherein the beryllium is in a crystal structure comprising equiaxed grains of beryllium; and a 2 Co、Be 2 Nb、Be2 She, Be 2 Ti、Be 2 W. Be 5 Hf、Be 5 Sc、Be 5 Zr、Be 7 Cu 13 、BeFe 3 , Cu 3 Mo, Cu 9 W, Mo, Nb, RbO 2 , ReRh, Ta, TiV and W to form grains that are 1:1 or 2:1 lattice matched with the beryllium grains; wherein the equiaxed grains of beryllium have an average grain size of 1 to 80 microns.

[0080] Embodiment 29 is an embodiment of embodiment 28, wherein the crystal structure comprises 50 volume % to 100 volume % equiaxed grains.

[0081] Although the present invention has been described in detail, based on the above discussion, relevant knowledge in the art and the references discussed above in connection with "background" and "detailed description" (the disclosures of which are all incorporated herein by reference), it is easy for those skilled in the art to see modifications within the spirit and scope of the present invention. In addition, it should be understood that aspects of the present invention and parts of various embodiments and various features listed below and / or in the appended claims may be combined or interchanged in whole or in part. In the previous description of various embodiments, those embodiments with reference to another embodiment may be appropriately combined with other embodiments as recognized by those skilled in the art. In addition, it will be appreciated by those of ordinary skill in the art that the previous description is only by way of example and is not intended to be limiting.

Claims

1. A method of making an object comprising beryllium, the method comprising: preparing a mixture of beryllium powder and at least one metal inoculant; depositing a layer comprising the mixture on a surface; applying energy to at least a portion of the layer in a reducing atmosphere to form molten beryllium; solidifying the molten beryllium into a layer comprising a continuous beryllium matrix having an equiaxed grain crystal structure; and The deposition / application / solidification process is repeated for subsequent layers until an object having a geometric shape is obtained.

2. The method of claim 1, wherein at least a portion of the metal inoculant is bonded to a surface of the beryllium powder.

3. The method according to any one of claims 1 or 2, wherein the at least one metal inoculant comprises a metal selected from the group consisting of Be2Co, Be2Nb, Be2Ta, Be2Ti, Be2W, Be5Hf, Be5Sc, Be5Zr, Be7Cu 13 , BeFe3, Cu3Mo, Cu9W, Mo, Nb, RbO2, ReRh, Ta, TiV and W.

4. The method of any one of claims 1 or 2, wherein the at least one metal inoculant comprises at least one particle selected from the group consisting of Be2Co, Be2Nb, Be2Ta, Be2Ti, Be2W, Be5Hf, Be5Sc and Be5Zr.

5. The method of any one of claims 1 to 4, wherein the continuous beryllium matrix has an average grain size of 1 to 80 microns.

6. The method of any one of claims 1 to 4, wherein the continuous beryllium matrix has an average grain size of 5 to 40 microns.

7. The method of any one of claims 1 to 4, wherein the continuous beryllium matrix has an average grain size of 5 to 25 microns.

8. The method according to any one of claims 1 to 7, wherein the mixture is prepared by blending, atomization, mechanical alloying or resonance mixing.

9. The method according to any one of claims 1 to 7, wherein the mixture comprises 90 to 99.99% by weight of beryllium.

10. The method according to any one of claims 1 to 7, wherein the mixture comprises 0.01 to 10% by weight of the at least one metal inoculant.

11. The method according to any one of claims 1 to 10, wherein energy is applied to at least a portion of the layer using an electron beam or a laser.

12. The method according to any one of claims 1 to 11, wherein the reducing atmosphere has a volume concentration of oxygen or other oxidizing agent of 10% by volume or less.

13. The method of any one of claims 1 to 12, wherein the beryllium powder has a D50 average particle size of 10 to 50 microns.

14. The method of any one of claims 1 to 13, wherein the at least one metal inoculant has a D50 average particle size of 0.001 to 5 microns.

15. An object prepared by the method according to claim 1, comprising: Beryllium, wherein the beryllium is in a crystal structure comprising equiaxed grains of beryllium; and Selected from Be2Co, Be2Nb, Be2Ta, Be2Ti, Be2W, Be5Hf, Be5Sc, Be5Zr, Be7Cu 13 , BeFe3, Cu3Mo, Cu9W, Mo, Nb, RbO2, ReRh, Ta, TiV and W to form grains that are 1:1 or 2:1 lattice matched to the beryllium grains; The equiaxed grains of beryllium have an average grain size of 1 to 80 microns.