Aluminum alloy

Abstract

To provide alloys that are high performance and economically feasible for Additive Manufacturing (AM) in various automotive, aerospace, and / or other engineering applications.SOLUTION: According to some configurations of the present disclosure, an alloy may include a composition that comprises approximately 5 to 12 wt.% of magnesium (Mg), approximately 0.1 to 2 wt.% of manganese (Mn), approximately 0.3 to 3 wt.% of silicon (Si), and the balance being aluminum (Al). In one configuration, the composition may further include one or more of iron (Fe), titanium (Ti), zirconium (Zr), chromium (Cr), and / or yttrium (Y).SELECTED DRAWING: Figure 2A

Description

[Technical field]

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS This application claims the benefit of U.S. Provisional Application No. 62 / 794,509, filed January 18, 2019, and entitled "HIGH-PERFORMANCE ALUMINUM ALLOY," and U.S. patent application Ser. No. 16 / 526,691, filed July 30, 2019, and entitled "ALUMINUM ALLOYS," which are hereby expressly incorporated by reference in their entireties.

[0002] Technical Field The present disclosure relates generally to alloys, and more specifically to aluminum alloys. [Background technology]

[0003] Additive manufacturing (AM) processes involve the use of stored geometric models to accumulate layers of material on a "build plate" to generate a three-dimensional (3D) object with features defined by the stored geometric model. AM techniques can print complex parts using a variety of materials. 3D objects are manufactured based on a computer-aided design (CAD) model. The AM process can produce solid three-dimensional objects directly from the CAD model without the use of additional tooling.

[0004] One example of an AM process is powder bed fusion (PBF), which uses a laser, electron beam, or other energy source to sinter or melt metal powder deposited in a powder bed, thereby consolidating the powder particles together at a target area to generate a 3D structure having a desired geometry (shape). In PBF, a variety of materials or combinations of materials may be used to create the 3D object, such as metals, plastics, and ceramics. Other, more advanced AM techniques are available or currently under development, including those discussed further below, each of which may be applicable to the present disclosure.

[0005] Another example of an AM process is called Binder Jetting (BJ), which uses a powder bed (similar to PBF) in which metal powders are spread in layers and bound together using an organic binder. The resulting part is a green part that must be sintered to burn off the binder and consolidate the layers to full density. This metal powder material can have the same chemical composition and similar physical properties as the PBF powder.

[0006] Another example of an AM process is called Directed Energy Deposition (DED). DED is an AM technique that uses laser, electron beam, plasma, or other energy delivery methods, such as those in tungsten-inert gas (TIG) or metal-inert gas (MIG) welding, to melt metal powder or wires and rods, thereby converting them into solid metal objects. Unlike many AM techniques, DED is not based on a powder bed. Instead, DED uses a feed nozzle to propel the powder, or a mechanical feed system to deliver wires and rods into a laser beam, electron beam, plasma beam, or other energy stream. The powdered metal or wires and rods are then fused together by the respective energy beam. Although supports or freeform substrates may be used to maintain the structure being built, in DED almost all of the raw material (powder, wire, or rod) is converted into solid metal, resulting in almost no waste powder remaining for recycling. Additionally, a printhead, consisting of a beam or stream of energy and a raw material delivery system, can scan the substrate and deposit successive layers directly from a CAD model using a layer-by-layer strategy.

[0007] PBF, BJ, DED, and other AM processes may use a variety of raw materials, such as metal powders, wires, or bars. The raw materials may be made from a variety of metallic materials. The metallic materials may include, for example, aluminum, or alloys of aluminum. It may be advantageous to use alloys of aluminum that have properties that improve their functionality within the AM process. For example, particle shape, powder size, packing density, melting point, flowability, stiffness, porosity, surface texture, density of charge, and other physical and chemical properties may affect how the aluminum alloy performs as an AM material. Similarly, the raw materials for the AM process may be in the form of wires or bars, but the chemical composition and physical properties of the wires or bars may affect the performance of the material. Some alloys may affect one or more of these or other properties that affect the performance of the alloy for AM.

[0008] One or more aspects of the present disclosure may be described in the context of the related art described above. None of the aspects described herein should be construed as an admission of prior art unless expressly stated herein. Summary of the Invention [Means for solving the problem]

[0009] Several embodiments of one or more alloys and alloy compositions, as well as methods of making and / or using them, are described herein. For example, the one or more alloys or compositions thereof may be an aluminum alloy. The one or more alloys may be used in three-dimensional (3D) printing and / or additive manufacturing to produce additively manufactured structures using the one or more alloys. Illustratively, the alloy may include a composition containing multiple materials (e.g., elements, metals, etc.).

[0010] According to some configurations of the present disclosure, the alloy may include a composition comprising: magnesium (Mg) at about 5-12 wt.% of the composition; silicon (Si) at about 0.3-3 wt.% of the composition; manganese (Mn) at about 0.1-2 wt.% of the composition; and aluminum (Al) at the balance of the composition. In one configuration, the composition may further comprise at least one of iron (Fe), chromium (Cr), titanium (Ti), zirconium (Zr), and yttrium (Y). In one configuration, the composition comprises up to about 5 wt.% Cr. In one configuration, the composition comprises up to about 0.25 wt.% Fe. In one configuration, the composition comprises at least 0.05 wt.% Fe. In one configuration, the composition comprises at least about 1 wt.% Cr. In one configuration, the composition comprises at least about 0.1 wt.% Ti. In one configuration, the composition comprises up to 0.6 wt.% Ti. In one configuration, the composition includes up to about 2 wt.% Zr. In one configuration, the composition includes at least 0.3 wt.% Zr. In one configuration, the composition includes at least about 0.1 wt.% Y. In one configuration, the composition includes up to 4 wt.% Y. In one configuration, the composition includes all of the elements listed above (Al, Mg, Mn, Si, Fe, Cr, Ti, Zr, and Y). In one configuration, the balance of the composition includes trace impurities, Al, up to about 0.1 wt.% cumulatively and up to 0.01% individually.

[0011] It will be understood that other aspects of the alloy will become readily apparent to those skilled in the art from the following detailed description, in which only certain embodiments are shown and described for purposes of illustration. As those skilled in the art will appreciate, the structures produced and the methods for producing these structures are capable of other and different embodiments, and their several details may be modified in various other respects, all without departing from the invention. Accordingly, the drawings and detailed description are to be regarded as illustrative in nature and not restrictive. [Brief description of the drawings]

[0012] Various aspects of alloys that may be used for additive manufacturing, for example in automotive, aerospace and / or other engineering contexts, are presented in the detailed description, by way of example and not by way of limitation, in the accompanying drawings.

[0013] [Figure 1A] FIG. 1A is a graph illustrating the properties of the alloy. [Figure 1B] FIG. 1B is a graph illustrating the properties of the alloy. [Figure 2A] FIG. 2A illustrates a side view of an exemplary 3D printer system. [Figure 2B] FIG. 2B illustrates a side view of an exemplary 3D printer system. [Figure 2C] FIG. 2C illustrates a side view of an exemplary 3D printer system. [Figure 2D] FIG. 2D illustrates a side view of an exemplary 3D printer system. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0014] The detailed description set forth below in conjunction with the accompanying drawings is intended to provide a description of various exemplary embodiments of the aluminum alloy, and is not intended to represent the only embodiments in which the present invention may be practiced. The term "exemplary" as used throughout this disclosure means "serving as an example, instance, or illustration," and should not necessarily be construed as preferred or advantageous over other embodiments presented in the present disclosure. The detailed description includes specific details for the purpose of providing a thorough and complete disclosure that fully conveys the scope of the invention to those skilled in the art. However, the techniques and approaches of the present disclosure may be practiced without these specific details. In some instances, well-known structures and components may be shown in block diagram form, or omitted entirely, in order to avoid obscuring various concepts presented throughout the present disclosure.

[0015] Metal alloys, such as aluminum alloys, are often utilized in various engineering applications, such as automotive and aerospace. In many applications, these engineering applications can benefit from alloys that provide high performance and durability. Furthermore, alloys that include, for example, rare and / or expensive elements may not be practical for relatively large-scale and / or commercial applications, and therefore, economical alloys may be more advantageous.

[0016] Although several alloys exist that meet the above criteria, these existing alloys are largely unsuitable for additive manufacturing (AM) applications such as selective laser melting (SLM) and / or powder bed fusion (PBF). For example, AM processes using alloys commonly used in conventional manufacturing (i.e., non-AM manufacturing) can result in unacceptable microstructures and / or other properties of these alloys, for example, by resulting in defective and / or unsafe products.

[0017] AM processes may involve, for example, very small melt pools and / or very high cooling rates for the alloy from the liquid to the solid state as compared to conventional manufacturing processes. Thus, alloys used in AM processes may be expected to develop microstructures and / or other properties (e.g., through relatively small melt pools and / or relatively high cooling rates) that result in high strength, ductility, fracture toughness, fatigue strength, corrosion resistance, and / or high temperature strength, and therefore may result in satisfactory products.

[0018] In view of the above, there is a need for high performance, economically feasible alloys for AM in various automotive, aerospace, and / or other engineering applications. The present disclosure describes alloys that can be implemented in AM processes such as SLM, PBF, DED, etc. In this manner, additively manufactured structures of the alloys disclosed herein, for example, may be produced. The alloys of the present disclosure may provide improved properties for AM in automotive, aerospace, and / or other engineering applications. The alloys may provide improved performance in the context of AM, such as one or more of high strength (e.g., yield strength), ductility, fracture toughness, fatigue strength, corrosion resistance, high temperature strength, percent elongation, and / or any combination thereof. Furthermore, application of the alloys of the present disclosure may be economically feasible in a commercial context and / or production scale, for example, for AM in automotive, aerospace, and / or other engineering applications.

[0019] In one aspect, high performance aluminum alloys are described. Crashworthiness is the combination of tensile, shear, and compressive strength that constitutes the crashworthiness of a material. Analytical and experimental data are utilized by various industries (e.g., automotive) in designing and building structures incorporating the material.

[0020] High performance aluminum alloys processed by conventional techniques (e.g., non-AM processes) may obtain various properties through one or a combination of the following processes: solid solution strengthening, strain hardening, precipitation strengthening, and / or dispersion strengthening. The processes of solid solution strengthening, strain hardening, precipitation strengthening, grain or phase boundary strengthening, and / or dispersion strengthening may occur during solidification, a subsequent heat treatment, an intermediate cold work, or any combination thereof.

[0021] The solidification process in AM and subsequent cooling in the solid state may differ from those occurring in conventional techniques. For example, solidification in PBF processing occurs layer by layer on a microscale, with each layer undergoing one or more cycles of melting, solidification, and cooling. In such a process, melting may begin at about 610°C and end at about 696°C. Due to the small size of the melt pool, the cooling rate is significantly higher than in conventional techniques, e.g., the cooling rate can be as low as about 10°C. 3 °C / sec (s) to about 10 6 °C / sec. Therefore, non-equilibrium thermodynamics and phase transformation kinetics become the dominant driving factors during AM, which may lead to alloys exhibiting different properties due to AM, such as inherited elemental supersaturation and alloy partitioning.

[0022] All alloys (e.g., AA4046, etc.) may contain relatively small weld pools (and may have a maximum of about 10 3 ℃ / s~about 10 6 In some embodiments, the alloys may be suitable for rapid solidification by AM (which may include rates of 1000 °C / s). In this disclosure, we describe alloys that may provide enhanced performance in AM, e.g., compared to currently available alloys. The performance of these alloys of this disclosure may be improved in the as-printed state, after undergoing, e.g., heat treatment (post-AM), or some combination of both as-printed and after undergoing heat treatment.

[0023] In one exemplary configuration, one or more alloys of the present disclosure may be tailored for good strengthening, such that the one or more alloys have high ultimate strength and tensile strength at room temperature and at elevated temperatures. In another exemplary configuration, one or more alloys of the present disclosure may be designed for good ductility, such that the one or more alloys have high elongation at room temperature and at elevated temperatures.

[0024] One or more alloys of the present disclosure may be specifically designed to accommodate the rapid melting, solidification, and / or cooling experienced by the alloy during AM (e.g., PBF process). For example, the alloying elements and their concentrations may be configured to form intermetallic compounds with other alloying elements during quenching. Additionally, the alloying elements and their concentrations may be configured based on the liquid and / or solid solubility of the alloying elements in the aluminum matrix. The alloying elements and their concentrations may be configured to form supersaturated solid solutions and / or nano-precipitates after rapid solidification and cooling during AM (e.g., PBF process). The alloying elements and their concentrations may be configured to form intermetallic compounds and their phases during subsequent heat treatments, including, for example, precipitation heat treatments and / or hot isostatic pressing (HIP). Finally, the alloying elements and their concentrations may be configured to form targeted specific intermetallic compounds during rapid solidification and cooling, such that the phases formed thereby enhance the performance of one or more alloys of the present disclosure. Additionally, the configuration of alloying elements and their concentrations may result in the formation of phases during subsequent heat treatment that improve the mechanical performance of one or more alloys of the present disclosure.

[0025] The one or more alloys of the present disclosure are composed of the balance Al. In some embodiments, the balance may include up to 0.1 wt.% trace elements. Al may be alloyed with a set of other materials, such as one or more elements. Exemplary elements that may be used to form the Al alloy in some configurations may include magnesium (Mg), manganese (Mn), silicon (Si), chromium (Cr), titanium (Ti), zirconium (Zr), yttrium (Y), and / or some combination of all or part of the set of elements listed above.

[0026] One or more alloys of the present disclosure may be compositions comprising Mg, Mn, Si, and Al. According to various configurations, Mg may be about 5%-12% by weight of the composition, Mn may be about 0.1%-2% by weight of the composition, Si may be about 0.3%-3% by weight of the composition, and Al may be the balance of the composition. According to some further configurations, the compositions of one or more alloys of the present disclosure may include at least one of Fe, Cr, Ti, Zr, and / or Y.

[0027] In alloying, various properties may be derived through different elements, for example, when they are in solid solution with Al. For example, strengthening properties may be derived through Mg and / or Mn, when they are in solid solution with Al. However, the addition of Mg and / or Mn may reduce ductility due to the formation of intermetallic compounds based on the solubility of Mg and / or Mn. Table 1 shows the solid solution strengthening potential of various alloying elements in aluminum alloys. As shown, the greatest solid solution strengthening potential may come from Mg and Mn, for example, when measured in the order of thousand pounds per square inch or kilopounds per square inch (ksi).

[0028] [Table 1]

[0029] Some existing Al alloys (e.g., 3000-series and 5000-series Al alloys) manufactured by conventional processing are based on the addition of Mg and Mn in Al. The content of Mn in 3000-series Al alloys may be 0.2%-1.2%, and the content of Mg in 5000-series Al alloys may be 0.5%-5.51%. As another existing alloy, aluminum alloy (AA) 6061 may have high strength and ductility, for example, for applications in aerospace engineering. However, AA6061 may not be suitable for AM applications. In particular, the PBF process using AA6061 may produce undesirable results.

[0030] As described herein, AM may be associated with relatively high melting temperatures and relatively fast cooling, for example, as compared to conventional or non-AM processing techniques. The fast cooling rates associated with AM may increase the solubility limits of various elements included in one or more of the alloys described herein, thereby resulting in a relatively finer microstructure as compared to conventional or non-AM processing techniques.

[0031] As noted above, one or more alloys of the present disclosure may include, in addition to Al, 5% to 12% (inclusive) Mg by weight of the alloy, which may be alloyed in combination with Mn to provide relatively high strength and / or ductility (e.g., compared to 3000 and 5000 series Al alloys). For example, one or more alloys of the present disclosure may include at least 7% Mg by weight of the alloy.

[0032] 1A and 1B show two graphs 100, 120 of the properties of Al alloyed with Mg and Mn. Referring to FIG 1A, the first graph 100 shows both the yield strength (in megapascals (MPa)) and tensile strength (in ksi (1 ksi is about 6.90 MPa)) of Al alloyed with weight percentages of Mg and Mn. As shown, both the yield strength and tensile strength of the Al alloy increase at least with weight percentages between about 2% Mg and greater than 7% Mg, and this range of Mg may be alloyed in combination with weight percentages between about 0.0% Mn and 0.9% Mn.

[0033] Referring to FIG. 1B, a second graph 120 shows the elongation (%) (in 50 millimeters (mm) / ≈2 inches (in)) of Al alloyed with weight percentages of Mg and Mn. As shown, the elongation (%) of the Al alloy may remain relatively high (e.g., greater than 20%, but may be less than 40%), at least for weight percentages between about 2% Mg and more than 7% Mg, and this range of Mg may be alloyed in combination with weight percentages between about 0.0% Mn and 0.9% Mn. Thus, as shown in FIG. 1A and FIG. 1B, Al may be alloyed with about 7 wt. % Mg (e.g., potentially less than 7 wt. % and / or potentially more than 7 wt. % Mg) to construct one or more alloys of the present disclosure having relatively high strength and ductility. As shown in Table 2, exemplary configurations of alloys having high strength and high ductility are shown.

[0034] [Table 2]

[0035] While Al alloyed with Mg and / or Mn may provide relatively high strength and / or high ductility, the relatively high strength may be derived from solid solution strengthening, but such alloys may not be heat treatable. Thus, one or more alloys of the present disclosure may be configured for solid solution strengthening as well as precipitation hardening. In doing so, one or more alloys of the present disclosure may be suitable for AM applications, including 3D printing. For example, one or more alloys of the present disclosure may be configured with one or more other elements in addition to Mg and Mn and balance Al. The addition of one or more other elements may make one or more alloys described herein suitable for AM applications, such as 3D printing, while still providing relatively high strength, ductility, and / or durability.

[0036] The construction of one or more alloys of the present disclosure with Si may contribute to precipitation hardening of the one or more alloys. For example, Si may be included in an Al-Mg-Mn alloy. Construction with Si may contribute to precipitation hardening. By way of example, Table 3 shows various examples of Al-Mg-Mn-Si alloys that may be suitable for AM. According to some constructions, one or more of the alloys shown in Table 3 may be alloyed with one or more other elements, for example, as described herein.

[0037] [Table 3]

[0038] According to various configurations, one or more alloys of the present disclosure may include a set of primary elements: Al, Mg, Mn, and Si. Table 4 provides ranges of weight percent of one or more primary elements that may be used in the configuration of one or more alloys of the present disclosure.

[0039] [Table 4]

[0040] In addition to or as an alternative to Si, one or more alloys of the present disclosure may be constructed with one or more of a set of secondary elements: Fe, Ti, Zr, Cr, and / or Y. Table 5 provides ranges of weight percent of one or more secondary elements that may be used in constructing one or more alloys of the present disclosure. One or more alloys of the present disclosure may be constructed with all, none, or some of the above sets of secondary elements.

[0041] [Table 5]

[0042] According to a first example, one version of the composition may include the above weight percentages of Mg, Mn, and Si, with balance Al, and may further include up to about 0.25 wt.% Fe. In another version, the first example composition may include at least about 0.05 wt.% Fe.

[0043] Iron is the most common impurity found in aluminum. Iron has a high solubility in molten aluminum, therefore iron is easily dissolved during all melting stages of production. The solubility of iron in the solid state is very low and when controlled at the levels disclosed in the above compositions, it can precipitate in the alloy by forming FeAl3 and the more complex AlFeMgSi, depending on the cooling rate, to provide additional strength.

[0044] According to a second example, one configuration of the above composition may include the balance Al and the weight percentages of Mg, Mn, and Si mentioned above, and may further include up to about 0.6 wt.% Ti. In another configuration, the composition of the second example may include at least about 0.1 wt.% Ti. Titanium can be used primarily as a grain refiner for aluminum alloys. When used alone, the effect of titanium decreases with the holding time in the molten state and repeated remelting. However, titanium can be used in combination with chromium, which reduces the electrical conductivity and therefore has a significant effect on the resistivity of aluminum alloys.

[0045] According to a third example, one version of the composition may include the above weight percentages of Mg, Mn, and Si, with balance Al, and may further include up to about 2.0 weight percent Zr. In another version, the third example composition may include at least about 0.3 weight percent Zr.

[0046] According to a fourth example, one configuration of the above composition may include balance Al and the weight percentages of Mg, Mn, and Si mentioned above, and may further include up to about 5 wt.% Cr. In another configuration, the composition of the fourth example may include at least about 1 wt.% Cr. Chromium increases the elastic modulus of the solid solution and, when in the form of submicron precipitates, increases the strength of the composition. Chromium has a low diffusion rate and may form a very fine dispersed phase in the composition, which may be retained in solid solution of the composition to improve both the elastic modulus and strength. Chromium also reduces stress corrosion susceptibility and improves toughness.

[0047] According to a fifth example, one configuration of the above composition may include the above weight percentages of Mg, Mn, and Si, with balance Al, and may further include up to about 4 weight percent Y. In another configuration, the fifth example composition may include at least about 0.1 weight percent Y.

[0048] With reference to zirconium and yttrium, both elements can form complex but nano precipitates when available in small amounts. However, the present disclosure describes both zirconium and yttrium in relatively large amounts, which may improve the strength and toughness of the alloy after solid solution strengthening, thereby reducing its susceptibility to cracking at high cooling rates. Yttrium may be more effective than zirconium (e.g., in increasing solid solution strengthening and / or toughness), and the inclusion of one or both of the two elements in the amounts disclosed herein may balance their effectiveness against costs (e.g., in the manufacture of one or more alloys of the present disclosure).

[0049] In some exemplary applications, one or more alloys of the present disclosure may be used for additive manufacturing in automotive engineering. For example, one or more alloys described herein may be additively manufactured to produce nodes, joints, and / or other structures that may be applied to vehicles (e.g., cars, trucks, etc.). For example, one or more alloys described herein may be additively manufactured to produce all or a portion of a vehicle chassis, frame, body, etc.

[0050] The properties of one or more alloys described herein may contribute to the crashworthiness of structures manufactured from one or more alloys described herein. Additionally, one or more alloys of the present disclosure may be configured with materials (e.g., elements) described herein such that an additively manufactured product using at least a portion of the one or more alloys can reduce the weight of a vehicle at an appropriate insertion point (e.g., compared to existing approaches to vehicle manufacturing).

[0051] One or more alloys of the present disclosure may be characterized by properties and / or characteristics that exceed the corresponding properties and / or characteristics of various existing alloys, for example, in the context of AM applications. For example, Table 6 shows exemplary compositions of alloys described in the present disclosure, where the listed values ​​of the elements listed are the weight percent of each corresponding element. These values ​​include mechanical properties of the as-printed parts without subsequent machining or post-processing operations. The alloys of Tables 4-6 may include resulting mechanical properties that exceed those of conventionally forged AA6061-T6. For example, the yield strength of the alloy shown in Table 6 may be 266 MPa, the tensile strength of the alloy shown in Table 6 may be 391 MPa, and the elongation (%) of the alloy shown in Table 6 may be 11.3%.

[0052] [Table 6]

[0053] The AM process may use a variety of metal powders, such as one or more alloys of the present disclosure. Figures 2A-2D show respective side views of an exemplary 3D printer system. In this example, the 3D printer system is a powder bed fusion (PBF) system 200. Figures 2A-2D show the PBF system 200 in different stages of operation. It should also be noted that features of Figures 2A-2D and other figures of the present disclosure are not necessarily drawn to scale and may be drawn larger or smaller for purposes of better illustrating the concepts described herein.

[0054] The specific embodiments shown in Figures 2A-2D are some suitable examples of PBF systems employing the principles of the present disclosure. In particular, one or more of the aluminum alloys described herein may be used in at least one PBF system 200 described in Figures 2A-2D. While one or more aluminum alloys described herein may be suitable for a variety of AM processes (e.g., using a PBF system as shown in Figures 2A-2D), it will be understood that one or more aluminum alloys of the present disclosure may be suitable for other applications as well. For example, one or more aluminum alloys described herein may be used in other fields or areas of manufacturing without departing from the scope of the present disclosure. Thus, AM processes employing one or more aluminum alloys of the present disclosure should be considered exemplary and are not intended to limit the scope of the present disclosure.

[0055] According to some examples of the present disclosure, the aluminum alloy used in the PBF system 200 may be a composition including balance Al, Mg being at least 2% by weight of the composition, Mn being up to 2.5% by weight of the composition, and Si being up to 4% by weight of the composition. In a specific configuration, Mg may be 5-12% by weight of the composition, Mn may be 0.1-2% by weight of the composition, and Si may be 0.3-3% by weight of the composition.

[0056] In some further configurations, the composition may further comprise at least one element selected from the group of Fe, Ti, Zr, Cr, and / or Y. In one example, the composition may comprise Fe that is up to 1% by weight of the composition, for example, the composition may comprise Fe that is between 0.05% and 0.25% by weight of the composition, inclusive. In another example, the composition may comprise Ti that is between 0 and 1% by weight of the composition, for example, the composition may comprise Ti that is between 0.1% and 0.6% by weight of the composition, inclusive. In a further example, the composition may comprise Zr that is between 0.15 and 5% by weight of the composition, for example, the composition may comprise Zr that is between 0.3% and 2% by weight of the composition, inclusive. In yet another example, the composition may include at least 1 wt. % Cr of the composition, for example, the composition may include 1 wt. % to 5 wt. % Cr of the composition, inclusive. In yet another example, the composition may include at least 0.1 wt. % Y of the composition, for example, the composition may include 0.1 wt. % to 4 wt. % Y of the composition, inclusive. In one configuration, the composition includes all of the elements listed above (Al, Mg, Mn, Si, Fe, Cr, Ti, Zr, and Y). In one configuration, the composition includes trace impurities up to about 0.1 wt. % cumulatively, and up to 0.01% individually (e.g., for each individual element alloyed with the balance Al).

[0057] Prior to use in the PBF system 200, the elements of the aluminum alloy may be combined into a composition according to one of the examples / configurations described herein. For example, the elements in the respective concentrations described in one of the examples / configurations of the present disclosure may be combined when the elements are molten. The composition may be mixed while the elements are molten, for example to promote an even distribution of each element relative to the remaining Al. The molten composition may be cooled and atomized. Atomization of the composition may result in a metal powder containing elements of one of the examples / configurations of the present disclosure and that can be used in an additive manufacturing system such as the PBF system 200.

[0058] The PBF system 200 can include a depositor 201 capable of depositing each layer of metal powder, an energy beam source 203 capable of generating an energy beam, a deflector 205 capable of applying the energy beam to fuse the powder material, and a build plate 207 capable of supporting one or more build pieces, such as build piece 209. The PBF system 200 can also include a build floor 211 disposed within a powder bed receptacle. The walls 212 of the powder bed receptacle generally define the boundary of the powder bed receptacle, which is laterally sandwiched between the walls 212 and abuts a portion of the build floor 211 below. The build floor 211 can progressively lower the build plate 207 to allow the depositor 201 to deposit the next layer. The entire setup can be within a chamber 213, which can enclose other components, thus protecting the apparatus, allowing atmospheric and temperature regulation, and reducing contamination risks. The depositor 201 can include a hopper 215 that contains powder 217, such as a metal powder, and a leveller 219 that can level the top of each layer of deposited powder.

[0059] With particular reference to Figure 2A, this figure shows the PBF system 200 after slices of the build piece 209 have been fused but before the next layer of powder is deposited. In fact, Figure 2A shows a point in time where the PBF system 200 has already deposited and fused slices in multiple layers, e.g., 150 layers, to form the current state of the build piece 209, which is formed from, e.g., 150 slices. The multiple layers already deposited form a powder bed 221 that includes powder that has been deposited but not fused.

[0060] 2B shows the PBF system 200 at a stage where the build floor 211 can be lowered by the powder layer thickness 223. The lowering of the build floor 211 lowers the build piece 209 and powder bed 221 by the powder layer thickness 223, such that the top surfaces of the build piece and powder bed are lower than the top surface of the powder bed receptacle wall 212 by an amount equal to the powder layer thickness. In this manner, a space of consistent thickness equal to, for example, the powder layer thickness 223 can be formed above the top surfaces of the build piece 209 and powder bed 221.

[0061] 2C shows the PBF system 200 at a stage where the depositor 201 is positioned to deposit powder 217 in a space created on the top surface 226 of the build piece 209 and the powder bed 221 and bounded by the powder bed receptacle walls 212. In this example, the depositor 201 moves progressively over the defined space while discharging the powder 217 from the hopper 215. The leveler 219 can level (flatten) the discharged powder to form a powder layer 225 having a thickness substantially equal to the powder layer thickness 223 (see, e.g., FIG. 2B). Thus, the powder in the PBF system can be supported by a powder material support structure, which can include, for example, the build plate 207, the build floor 211, the build piece 209, the walls 212, etc. It should be noted that the illustrated thickness of powder layer 225 (i.e., powder layer thickness 223 (FIG. 2B)) is greater than the actual thickness used in the example including the pre-deposited layer of 150 described above with reference to FIG. 2A.

[0062] FIG. 2D illustrates the PBF system 200 at a stage following deposition of the powder layer 225 (FIG. 2C), where the energy beam source 203 generates an energy beam 227 and the deflector 205 applies the energy beam to fuse the next slice of the build piece 209. In various exemplary embodiments, the energy beam source 203 can be an electron beam source, in which case the energy beam 227 constitutes an electron beam. The deflector 205 can include deflection plates that can generate electric or magnetic fields that selectively deflect the electron beam so that it scans the designated area to be fused. In various embodiments, the energy beam source 203 can be a laser, in which case the energy beam 227 is a laser beam. The deflector 205 can include optics that use reflection and / or refraction to steer the laser beam to scan the selected area to be fused.

[0063] In various embodiments, the deflector 205 can include one or more gimbals and actuators that can rotate and / or translate the energy beam source to position the energy beam. In various embodiments, the energy beam source 203 and / or the deflector 205 can modulate the energy beam, for example, turning the energy beam on and off as the deflector scans, such that the energy beam is applied only in the appropriate areas of the powder bed. For example, in various embodiments, the energy beam can be modulated by a digital signal processor (DSP).

[0064] An alloy may be a substance that is composed of two or more materials (e.g., metals or non-metals) that may be bonded together, for example, by being fused together in a molten state.

[0065] In some configurations, one or more alloys of the present disclosure may be compositions that may be mixed to include the following materials: (1) Mg, balance 5-12% by weight of the composition, (2) Mn, about 0.1-2% by weight of the composition, (3) Si, about 0.3-3% by weight of the composition. In some configurations, the balance Al may include trace elements up to 0.1%.

[0066] In some other configurations, one or more alloys of the present disclosure may be the above-mentioned composition of Al, Mg, Mn, and Si, which may include at least one of the following other materials: Fe, Ti, Zr, Cr, and / or Y. When the alloy of the present disclosure is a composition including Fe, Fe may be 0.05-0.25 wt.% of the composition. When the alloy of the present disclosure is a composition including Ti, Ti may be 0.1-0.6 wt.% of the composition. When the alloy of the present disclosure is a composition including Zr, Zr may be 0.3-2 wt.% of the composition. When the alloy of the present disclosure is a composition including Cr, Cr may be 1-5 wt.% of the composition. When the alloy of the present disclosure is a composition including Y, Y may be 0.1-4 wt.% of the composition. In various configurations, one or more alloys of the present disclosure may include all, none, or some of the other materials: Fe, Ti, Zr, Cr, and / or Y.

[0067] Exemplary alloys of the present disclosure may be processed with the L-PBF method to print test bars, and tensile properties may be obtained from the exemplary alloys.

[0068] AM feedstocks can be produced by powder manufacturing processes as well as other methods such as ingot metallurgy (I / M), where a solid ingot is produced by melting metal with added alloying elements and solidifying it in a mould such as an ingot. The mould solid or ingot is then transformed by various wrought material manufacturing methods such as rolling, extrusion, drawing (drawing), etc. The resulting ingot, wire or bar is then melted and atomised into powder or fed directly into a laser beam, electron beam, plasma beam or electric arc such as TIG or MIG to melt the metal layer by layer to produce the AM product.

[0069] Powder properties can be important for successful fusion in an AM machine such as PBF and / or DED. Some aspects of alloy powders that may be advantageous for use in AM may include, but are not limited to, good flowability, tight particle packing, and spherical particle shape. These aspects can result in consistent and predictable layers.

[0070] The previous description is provided to enable one skilled in the art to practice the various aspects described herein. Various modifications to these exemplary embodiments presented throughout this disclosure will be readily apparent to one skilled in the art, and the concepts disclosed herein may be applied to aluminum alloys. Thus, the claims are not intended to be limited to the exemplary embodiments presented throughout this disclosure, but should be accorded the full scope consistent with the claims in technical terms. All structural and functional equivalents known or later known to those skilled in the art to the elements of the exemplary embodiments described throughout this disclosure are intended to be encompassed within the scope of the claims. Furthermore, nothing disclosed herein is intended to be dedicated to the public, whether or not such disclosure is expressly set forth in the claims. No element of a claim should be construed under the provisions of 35 U.S.C. 112(f) or any similar provision of the applicable jurisdiction unless the element is expressly recited using the phrase "means for" or, in the case of a method claim, the element is recited using the phrase "step for".

Claims

1. 1. An alloy comprising a composition, the composition comprising: Magnesium (Mg), at least 2% by weight of said composition; Manganese (Mn), up to 2.5% by weight of the composition; Silicon (Si), up to 4% by weight of the composition; and The balance of the composition is aluminum (Al). An alloy containing

2. The composition, Mg, which is 5 to 12% by weight of the composition; Mn, which is 0.1 to 2% by weight of the composition; and 0.3 to 3% by weight of the composition 2. The alloy of claim 1 comprising:

3. The composition, Iron (Fe), Titanium (Ti), Zirconium (Zr), Chromium (Cr), or Yttrium (Y) The alloy of claim 1 further comprising at least one of:

4. The composition, Fe, up to 1% by weight of said composition; Ti, which is 0-1 wt. % of said composition; 0.15 to 5 wt. % Zr of said composition; Cr, which is at least 1 wt. % of said composition; and At least 0.1% by weight of the composition 4. The alloy of claim 3 comprising:

5. 4. The alloy of claim 3, wherein the composition comprises up to 0.25 wt.% of said Fe.

6. 6. The alloy of claim 5, wherein said composition comprises at least 0.05 wt.% of said Fe.

7. 4. The alloy of claim 3, wherein the composition comprises up to 0.6 wt.% of said Ti.

8. 8. The alloy of claim 7, wherein said composition comprises at least 0.1 wt.% of said Ti.

9. 4. The alloy of claim 3, wherein the composition comprises up to 2.0 wt.% Zr.

10. 10. The alloy of claim 9, wherein said composition comprises at least 0.3 wt.% of said Zr.

11. 4. The alloy of claim 3, wherein the composition comprises up to 5 wt.% of said Cr.

12. 12. The alloy of claim 11, wherein said composition comprises at least 1 wt.% of said Cr.

13. 4. The alloy of claim 3, wherein the composition comprises up to 4 wt.% of said Y.

14. 14. The alloy of claim 13, wherein said composition comprises at least 0.1 wt.% of said Y.

15. 2. The alloy of claim 1, wherein said balance of said composition, said Al, contains up to 0.1 wt. % trace impurities.

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