Method of making beryllium-based articles

Abstract

A method of manufacturing a beryllium-based article object comprising beryllium by depositing a beryllium layer. An element is added to beryllium that dissolves to form a second phase to confine columnar grains. 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 / 409,101, 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 making a beryllium-based article. In particular, the method produces a beryllium-based article with an improved grain structure by adding elements that dissolve in molten beryllium to promote a fine grain structure and limit a columnar grain structure. The improved grain structure results in improved strength and processing. Background Art

[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 forming 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 provides a method for making a beryllium-based article, wherein elements such as aluminum, silicon and / or silver are added to beryllium powder. The element added to the beryllium powder may affect thermal activity. Once the element is added, this can change the molten pool behavior and obtain a fine grain structure with limited columnar structure. For beryllium-based articles, including those produced in complex three-dimensional shapes, improvements in strength and durability can be achieved.

[0008] In one embodiment, a method is provided, which includes that a layer comprising beryllium powder and an element such as aluminum, silicon and / or silver can be deposited on a surface, and energy can be applied to at least a portion of the layer from, for example, a laser or electron beam to form molten beryllium in which at least a portion of the element is dissolved. The molten beryllium can then solidify to form a second phase from the dissolved elements, and the process of deposition, heating and solidification can be repeated on subsequent layers to form a beryllium-based product. In one embodiment, the second phase can be dispersed between the beryllium grains. In one embodiment, the beryllium has an average grain size of 1 to 80 microns.

[0009] In one embodiment, a method of making a beryllium-based article is provided, the method comprising adding an element and a nucleant to a beryllium powder; depositing a layer comprising the beryllium powder on a surface; applying energy to at least a portion of the layer to form molten beryllium, wherein at least a portion of the element is dissolved in the molten beryllium; solidifying the molten beryllium, wherein the beryllium has an average grain size of 1 to 80 microns; and repeating the deposition / application / solidification for subsequent layers to form a beryllium-based article. In one embodiment, the element is effective for growth restriction and separation of the nucleant. Preferably, the nucleant may include beryllium titanium, beryllium chromium, iron beryllium, beryllium zirconium, tantalum beryllium, beryllium molybdenum, niobium beryllium, beryllium tungsten, beryllium strontium and / or beryllium hafnium.

[0010] These and other non-limiting features are more particularly described below. Details

[0011] 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.

[0012] 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.

[0013] The singular forms "a," "an," and "the" include plural referents unless the context clearly dictates otherwise.

[0014] 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 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.

[0015] The numerical values ​​in the specification and claims of this application, when they refer to compositions, articles or powders, 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 the value that differs from the specified value by less than the experimental error of the conventional measurement techniques of the type described in this application for determining the value.

[0016] 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.

[0017] 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.

[0018] 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.

[0019] As described herein, there is a method for making a beryllium-based article. The method includes adding an element to a beryllium powder, preferably an element that is at least partially dissolved in the molten beryllium. The presence of the element or solute in the molten beryllium can affect grain refinement by slowing the growth of the solid and assisting the segregation of nucleating agents. This mechanism leads to solute enrichment near the solidification interface. For the present disclosure, the element includes aluminum, silicon and / or silver. During the solidification process of the molten beryllium, the dissolved element can promote the formation of a second phase. In one embodiment, the second phase can promote fine grain size while beneficially limiting columnar structure. Without being bound by theory, the presence of the at least partially dissolved element can contribute to grain refinement of the beryllium-based article.

[0020] As used herein, the term "dissolve" means that the element dissolves in the molten beryllium to form a homogeneous solution.

[0021] In one embodiment, the beryllium-based article is made by a series of layers, wherein each layer is made by applying energy to a beryllium powder followed by solidification. In one embodiment, an element may be added to the beryllium powder deposited on a surface, and the beryllium powder may be heated by applying energy thereto to produce molten beryllium, wherein at least a portion of the element is dissolved in the molten beryllium. In one embodiment, the element is completely dissolved in the molten beryllium.

[0022] The undissolved portion of the element can provide nucleation sites, while the dissolved portion can be redistributed during solidification. In one embodiment, the molten beryllium can solidify to form a second phase from the dissolved element. In one embodiment, after sequential deposition / application / solidification, the second phase can be dispersed between the beryllium grains. When forming an article having a series of layers, the above-mentioned grain refinement of the beryllium-based article can bring improved strength and processing. In one embodiment, the beryllium-based 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-based article may have an aspect ratio of less than 3: 1. In particular, at least 75% of the grains of the beryllium-based article may have an aspect ratio of less than 3: 1, such as less than 2.5: 1 or less than 2: 1. 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 E112-12.

[0023] Elements with large growth restriction factors can be used as grain refiners to slow down the grain growth of beryllium. In one embodiment, aluminum, silicon, silver and / or a combination thereof are efficient solutes for grain refinement. Sufficient amounts of the element are added to achieve the desired grain refinement. In one embodiment, the element constitutes 0.1% to 25% by weight of the gross weight of the beryllium-based article, such as 0.1% to 20% by weight, 0.25% to 15% by weight, 0.25% to 10% by weight, 0.25% to 5% by weight, 0.5% to 5% by weight, or 0.5% to 1.5% by weight. When the amount of the element is greater than 25% by weight, the element tends to become more difficult to dissolve.

[0024] The element may be added to the beryllium powder. In one embodiment, a portion of the element may be bonded to the surface of the beryllium powder. Preferably, the element does not react with the beryllium powder when added.

[0025] In one embodiment, as the molten beryllium solidifies, a second phase is formed from the element. In one embodiment, after the molten beryllium solidifies, the second phase is dispersed between the beryllium grains.

[0026] In one embodiment, the element added to the beryllium powder includes a metal that provides a nucleation site for beryllium. The elements disclosed herein can affect nucleation by interfacial segregation and growth restrictions to affect grain refinement. The element can exist as a loose powder, paste or suspension that can be combined with beryllium. In one embodiment, the element remains unreacted when combined with beryllium powder. There are several methods to add the element to beryllium powder, such as mixing, blending, atomization, mechanical alloying, resonance mixing or a combination thereof. When the element is added to beryllium powders of different sizes to achieve adequate mixing, resonance mixing is useful. In one embodiment, resonance mixing uses a sound wave with a frequency of 20 to 80 Hz to induce non-contact acoustic mixing to achieve good mixing in a short time without causing rupture or stress of beryllium powder. In one embodiment, the element comprises silver, aluminum, silicon and / or a combination thereof.

[0027] In one embodiment, the beryllium powder containing the element is deposited as a layer, so no additional steps are required prior to deposition. Accordingly, a method of making a beryllium-based article is provided, comprising depositing a layer comprising beryllium powder on a surface, the beryllium powder comprising an element selected from the group consisting of silver, silicon and aluminum, cycling at least a portion of the layer above a temperature greater than or equal to the temperature required to form molten beryllium, solidifying the layer, and repeating the deposition / cycling / solidification for subsequent layers, wherein each subsequent layer comprises the beryllium powder. Preferably, the beryllium-based article has an average grain size of 1 to 80 microns.

[0028] In one embodiment, the element can be a metal powder. The metal powder can 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 can be smaller than beryllium powder. The metal powder can have an average (D) less than or equal to 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 have an average (D 50 ), such as less than 1 micron. 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 )granularity.

[0029] In one embodiment, the beryllium powder may include beryllium. Various amounts of beryllium may be suitable for use with the embodiments disclosed herein. In an exemplary embodiment, the beryllium powder includes beryllium in an amount greater than 40% by weight. In one embodiment, the beryllium powder may include beryllium in an amount of 40% to 95% by weight. More preferably, the beryllium powder may include beryllium in an amount of 50% to 95% by weight, such as 60% to 95% by weight or 80% to 95% by weight.

[0030] In another embodiment, the beryllium powder can be 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 can 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. In one embodiment, the beryllium powder can be spherical. The beryllium powder can 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-based products with reduced grain refinement. When necessary, the beryllium powder can be screened to achieve the desired size.

[0031] In one embodiment, the beryllium powder can be in the form of particles with a core-shell structure, wherein beryllium constitutes the core and a continuous or semi-continuous coating constitutes the shell. The coating of beryllium can be achieved by ball milling, resonance mixing, spray bonding, 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.

[0032] In one embodiment, the beryllium powder can have at least a portion of the element bonded to a surface of the beryllium powder.

[0033] The element may be combined with beryllium in an effective amount to promote fine grain size and limit columnar structure. In one embodiment, the amount of the element combined with the beryllium powder may be 0.1 to 25 wt % based on the total weight of the beryllium powder. More preferably, the element may be present in an amount of 0.1 to 10 wt %, such as 0.25 to 10 wt %, 0.25 to 8 wt %, 0.5 to 5 wt %, or 0.5 to 1.5 wt %.

[0034] In one embodiment, the element is silver, which can be added to the beryllium powder in an effective amount to promote fine grain size and limit columnar structure. Silver can be effective for grain refinement to produce an article with improved strength and performance. In one embodiment, silver can be present in the beryllium powder in an amount of 0.1 to 25 weight % based on the total weight of the beryllium powder. More preferably, silver can be present in an amount of 0.1 to 10 weight %, such as 0.25 to 10 weight %, 0.25 to 8 weight %, 0.5 to 5 weight %, or 0.5 to 1.5 weight %.

[0035] In one embodiment, the element is aluminum, which can be combined with beryllium in an effective amount to promote fine grain size and limit columnar structure. Aluminum can be effective for grain refinement to produce products with improved strength and performance. In one embodiment, aluminum can be present in the beryllium powder in an amount of 0.1 to 25 weight percent based on the total weight of the beryllium powder. More preferably, aluminum can be present in an amount of 0.1 to 10 weight percent, such as 0.25 to 10 weight percent, 0.25 to 8 weight percent, 0.5 to 5 weight percent, or 0.5 to 1.5 weight percent.

[0036] In one embodiment, the element is silicon, which can be combined with beryllium in an effective amount to promote fine grain size and limit columnar structure. Silicon can be effective for grain refinement to produce an article with improved strength and performance. In one embodiment, silicon can be present in the beryllium powder in an amount of 0.1 to 25 weight % based on the total weight of the beryllium powder. More preferably, silicon can be present in an amount of 0.1 to 10 weight %, such as 0.25 to 10 weight %, 0.25 to 8 weight %, 0.5 to 5 weight %, or 0.5 to 1.5 weight %.

[0037] In one embodiment, the element is a combination of silver, silicon and / or aluminum, which can be combined with beryllium in an effective amount to promote fine grain size and limit columnar structure. The combination of silver, silicon and / or aluminum can be effective for grain refinement to produce products with improved strength and performance. In one embodiment, the combined silver, silicon and / or aluminum can be present in the beryllium powder in an amount of 0.1 to 25 weight % based on the total weight of the beryllium powder. More preferably, the combined silver, silicon and / or aluminum can be present in an amount of 0.1 to 10 weight %, such as 0.25 to 10 weight %, 0.25 to 8 weight %, 0.5 to 5 weight %, or 0.5 to 1.5 weight %.

[0038] The beryllium powder may also contain a nucleating agent for grain refinement. In one embodiment, the beryllium powder may contain an intermetallic compound of beryllium that acts as a nucleating agent. In one embodiment, the intermetallic compound of beryllium is a beryllium compound, such as beryllium titanium (Be 12 Ti, Be2Ti), beryllium chromium (Be2Cr or Be 12 Cr), beryllium iron (FeBe5), beryllium zirconium (Be 13 Zr, Be5Zr, Zr2Be 17 ), Tantalum Beryllium (TaBe2, Ta2Be 17 、TaBe 12 or TaBe 17 ), beryllium molybdenum (Be2Mo, Be 12 Mo, Be 22 Mo), niobium beryllium (NbBe2, NbBe3, Nb2Be 17、NbBe 12 ), beryllium tungsten (Be 22 W), beryllium strontium (Be 13 The nucleating agent may be present in an amount of 0 to 40 wt %, such as 0 to 35 wt %, 0 to 30 wt %, 0.5 to 35 wt %, 1 to 30 wt %, or 1 to 20 wt %, based on the total weight of the beryllium powder.

[0039] In one embodiment, the beryllium powder may be in the form of particles, such as a powder. The particles may have a D50 average particle size of 10 to 50 microns, such as 15 to 50 microns, 20 to 45 microns, or 25 to 40 microns.

[0040] method

[0041] By cycling several deposited beryllium powder layers, a beryllium-based product can be formed. After applying energy to form molten beryllium, the added elements in the beryllium powder can be at least partially dissolved therein and form a second phase when solidified. 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 beryllium powder 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.

[0042] The method may begin by depositing an initial layer in a build box. Preferably, the beryllium powder to which the element is added 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 side walls. 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 side walls cooperate with the build platform to form a "box" containing the deposited beryllium powder. Typically, the side walls remain in a fixed position and the build platform moves downward to allow the next layer of beryllium powder to be deposited.

[0043] The initial 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 defined by an x-axis and a y-axis, wherein the x-axis, the y-axis and the z-axis are orthogonal to each other.

[0044] 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 the beryllium powder layer is deposited, energy can be applied in a reducing atmosphere. In one embodiment, the reducing atmosphere contains less than or equal to 20% oxygen by volume, such as less than 15% by volume, less than 10% by volume, or less than 5% by volume.

[0045] In one embodiment, each layer can be deposited in a uniform manner. The initial layer can 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, the layer can be formed by compacting the deposited beryllium powder with an optional compaction 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.

[0046] After depositing the initial layer, the method uses a cycling process to heat the initial layer to a temperature sufficient to form molten beryllium, followed by cooling the layer. In one embodiment, the cycling process can be rapid to improve productivity and efficiency. In one embodiment, the cycle further includes exposing the deposited initial layer to an energy source. The cycle transitions through a thermal gradient at a high rate to solidify the beryllium-based product. In one embodiment, the 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. 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 2The energy source is operated at a power sufficient to induce heat above a temperature sufficient to form molten beryllium. In one embodiment, the effective diameter of the energy source may be 10 to 200 microns, such as 25 to 150 microns, or 35 to 100 microns. The scanning speed of the energy source may be 10 mm / s to 2000 mm / s, such as 50 mm / s to 1500 mm / s or 100 mm / s to 1000 mm / s. The raster width of the energy source may 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 may be 20 to 200 microns, such as 25 to 175 microns or 50 to 150 microns.

[0047] In one embodiment, the energy source and / or another source heats the initial layer to a temperature sufficient to form molten beryllium. In one embodiment, the temperature may be 1000°C to 1500°C, such as 1100°C to 1450°C, 1200°C to 1400°C, or 1290°C to 1325°C. In one embodiment, the cycle process may be fast to increase productivity. The cycle process may last less than or equal to 300 seconds, such as 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, the rapid cycle may be 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.

[0048] Unless preheating is used, the initial layer can be deposited at room temperature (20 to 25° C.). In some embodiments, the deposited initial material 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.

[0049] Operating the method at reduced atmospheric pressure or under vacuum can provide quality control for the layer and beryllium-based article material. Nevertheless, in some embodiments, the method can be operated at atmospheric pressure.

[0050] 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, cooling can be in the building direction of the layer. During the solidification process, a second phase can be formed by the dissolved elements. The second phase can be dispersed between the beryllium grains and can contribute to grain refinement.

[0051] A coolant can be used to achieve the desired cooling by removing excess energy applied to the layer. The coolant can further reduce the temperature gradient in the layer that tends to form columnar grains and thereby improve grain refinement. In one embodiment, the coolant can be an inert gas, such as nitrogen or a noble gas, particularly argon. The coolant can be a mixture of gases. The coolant can be delivered to the layer as a focussed gaseous 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 can 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 while depositing the layer, and may be less than or equal to 500 L / min, such as less than 250 L / min or less than 100 L / min.

[0052] 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.

[0053] In one embodiment, the beryllium powder can be heated to a temperature sufficient to form molten beryllium. In one embodiment, at least a portion of the element can be dissolved in the molten beryllium. In one embodiment, the element is completely dissolved in the beryllium. In one embodiment, the amount of dissolved element is less than the total amount of the element added to the beryllium. In one embodiment, the amount of dissolved element is less than the total amount of the element added to the beryllium. Once dissolved, the element is freely available to restrict growth.

[0054] In one embodiment, the ratio of dissolved elements to undissolved elements is from 0.1 to 50 to 50 to 0.1; for example, 0.5 to 40, 1 to 20, 5 to 10, 1 to 1, 10 to 5, 20 to 1, 40 to 0.5, or 50 to 0.1.

[0055] The method can continue in a similar manner for subsequent layers, thereby circulating and solidifying the molten beryllium in each deposited beryllium powder layer. After leaving enough time for solidification, one or more subsequent layers can be deposited in a predetermined pattern on at least a portion of the initial layer opposite to the surface. This continues to build a beryllium-based 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 sufficient to dissolve the element partially or completely in the molten beryllium. In one embodiment, the energy source is controlled within operating parameters similar to 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.

[0056] 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-based article. The method may continue to repeat deposition, circulation, and precipitation until the desired beryllium-based article is formed. In one embodiment, a three-dimensional object is formed. In one embodiment, the beryllium-based article 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 articles, hundreds of layers may be used, so the number of layers is not limited.

[0057] The orientation of the microstructure is not limited to the build direction of subsequent layers. The microstructure of the beryllium-based article may contain multiple dendrite layers with different primary growth direction angles relative to each other. This provides a crack-free beryllium-based article.

[0058] In some embodiments, the method further includes solidifying the multiple layers before sintering the preform. In one embodiment, the beryllium-based product can be solutionized and then quenched. The beryllium-based 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-based product made may have scattered or unfused particles in one or more layers. Unfused particles can be removed by blowing or vacuuming as needed.

[0059] 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.

[0060] 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").

[0061] Embodiment 1 is a method of making a beryllium-based article, the method comprising adding an element and a nucleating agent to a beryllium powder; depositing a layer comprising the beryllium powder on a surface; applying energy to at least a portion of the layer to form molten beryllium, wherein at least a portion of the element is dissolved in the molten beryllium; solidifying the molten beryllium, wherein the beryllium has an average grain size of 1 to 80 microns; and repeating the deposition / application / solidification steps for subsequent layers to form the beryllium-based article.

[0062] Embodiment 2 is an embodiment of embodiment 1, wherein the nucleating agent comprises beryllium titanium, beryllium chromium, iron beryllium, beryllium zirconium, tantalum beryllium, beryllium molybdenum, niobium beryllium, beryllium tungsten, beryllium strontium and / or beryllium hafnium.

[0063] Embodiment 3 is a version of embodiment 1, wherein the beryllium powder comprises 0 to 40 weight percent of a nucleating agent.

[0064] Embodiment 4 is a method for manufacturing a beryllium-based article, the method comprising adding an element to a beryllium powder; depositing a layer comprising the beryllium powder on a surface; applying energy to at least a portion of the layer to form molten beryllium, wherein at least a portion of the element is dissolved in the molten beryllium; solidifying the molten beryllium to form a second phase from the dissolved element; and repeating the deposition / application / solidification steps for subsequent layers to form the beryllium-based article.

[0065] Embodiment 5 is the embodiment of any one of embodiments 1-4, wherein the element comprises aluminum, silicon, or silver.

[0066] Embodiment 6 is an embodiment of any of embodiments 1-5, wherein the element is completely dissolved in the molten beryllium.

[0067] Embodiment 7 is the embodiment of any of embodiments 1-6, wherein the second phase is dispersed between the beryllium grains.

[0068] Embodiment 8 is the embodiment of any of embodiments 1-7, wherein the beryllium grains have an average grain size of 1 to 80 microns.

[0069] Embodiment 9 is the embodiment of any of embodiments 1-7, wherein the beryllium grains have an average grain size of 5 to 40 microns.

[0070] Embodiment 10 is the embodiment of any of embodiments 1-7, wherein the beryllium grains have an average grain size of 5 to 25 microns.

[0071] Embodiment 11 is the embodiment of any of embodiments 1-10, wherein the element and / or nucleating agent is added to the beryllium powder by blending, atomization, mechanical alloying, or resonance mixing.

[0072] Embodiment 12 is the embodiment of any of embodiments 1-11, wherein 0.1 to 25 weight percent of the element is added to beryllium.

[0073] Embodiment 13 is the embodiment of any of embodiments 1-12, wherein 0.1 to 10 wt % of the element is added to beryllium.

[0074] Embodiment 14 is the embodiment of any of embodiments 1-13, wherein energy is applied to at least a portion of the layer using an electron beam or a laser.

[0075] Embodiment 15 is the embodiment of any one of embodiments 1-14, further comprising depositing the layer in a reducing atmosphere.

[0076] Embodiment 16 is an embodiment of any one of embodiments 1-15, wherein the reducing atmosphere has a volume concentration of oxygen or other oxidants of 10 volume % or less.

[0077] Embodiment 17 is the embodiment of any of embodiments 1-16, wherein the beryllium powder has a D50 average particle size of 10 to 50 microns.

[0078] 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 for manufacturing a beryllium-based product, the method comprising: Adding elements to beryllium powder; depositing a layer comprising the beryllium powder on a surface; applying energy to at least a portion of the layer to form molten beryllium, wherein at least a portion of the element is dissolved in the molten beryllium; solidifying the molten beryllium to form a second phase from the dissolved element; and The depositing / applying / solidifying steps are repeated for subsequent layers to form the beryllium-based article.

2. The method of claim 1, wherein the element comprises aluminum, silicon or silver.

3. The method according to any one of claims 1 or 2, wherein the element is completely dissolved in the molten beryllium.

4. The method according to any one of claims 1 to 3, wherein the second phase is dispersed between beryllium grains.

5. The method of claim 4, wherein the beryllium grains have an average grain size of 1 to 80 microns, preferably an average grain size of 5 to 40 microns or preferably an average grain size of 5 to 25 microns.

6. The method according to any one of claims 1 to 5, wherein the element is added to the beryllium powder by blending, atomization, mechanical alloying or resonance mixing.

7. The method according to any one of claims 1 to 6, wherein 0.1 to 25% by weight of the element is added to beryllium.

8. The method according to any one of claims 1 to 7, wherein 0.1 to 10% by weight of the element is added to beryllium.

9. The method according to any one of claims 1 to 8, wherein energy is applied to at least a portion of the layer using an electron beam or a laser.

10. The method according to any one of claims 1 to 9, further comprising depositing the layer in a reducing atmosphere.

11. The method of claim 10, wherein the reducing atmosphere has a volume concentration of oxygen or other oxidizing agent of 10 volume % or less.

12. The method of any one of claims 1 to 11, wherein the beryllium powder has a D50 average particle size of 10 to 50 microns.

13. The method according to any one of claims 1 to 12, wherein a nucleating agent is added to the beryllium powder.

14. The method of claim 13, wherein the nucleating agent comprises beryllium titanium, beryllium chromium, iron beryllium, beryllium zirconium, tantalum beryllium, beryllium molybdenum, niobium beryllium, beryllium tungsten, beryllium strontium and / or beryllium hafnium.

15. The method of claim 13, wherein the beryllium powder comprises 0 to 40 wt% of the nucleating agent.