Laser powder bed fusion of nanocrystalline amorphous particle reinforced aluminum matrix composites, methods, and applications

Abstract

The application discloses a kind of laser powder bed melting nanometer amorphous particle reinforced aluminum matrix composite material and method and application, the aluminum matrix composite material is stacked from below to above by multiple melting layers, each melting layer is stacked by multiple alloys in the vertical direction of stacking melting layer direction, the phase of each alloy is composed of superfine isometric alpha-Al phase and bulky columnar alpha-Al phase, all superfine isometric alpha-Al phase is distributed in alloy boundary, all bulky columnar alpha-Al phase is distributed in alloy interior, and superfine isometric alpha-Al phase and the bulky columnar alpha-Al phase connected constitute bimodal structure;Superfine isometric alpha-Al phase is diffusely distributed with nanometer aluminum iron nickel amorphous particle and nanometer Mg2Si intermetallic compound on grain boundary, and part of intracrystalline distribution has nanometer Al3 (Sc,Zr) Particle;Nanometer aluminum iron nickel amorphous particle and nanometer Mg2Si intermetallic compound distributed in bulky columnar alpha-Al phase interconnect and form cell network structure.The aluminum matrix composite material provided by the application has ultrahigh strength, good ductility, excellent thermal stability and wear resistance.

Description

TECHNICAL FIELD

[0001] The present application relates to a laser powder bed fusion nanometer amorphous particle reinforced aluminum matrix composite material and method and application, and belongs to the technical field of laser additive manufacturing (3D printing). BACKGROUND

[0002] Metal additive manufacturing (Additive Manufacturing, AM) technology has become an important research direction in the field of advanced manufacturing due to its unique advantages in rapid shaping of complex geometric components. As a typical representative of AM technology, laser powder bed fusion (Laser Powder Bed Fusion, L-PBF) technology provides a revolutionary technical platform for breaking through the traditional material processing limit and developing new alloy systems due to its high cooling rate (10 3 ~10 6 K / s) and layer-by-layer processing characteristics.

[0003] In the aluminum alloy system, the traditional metallurgical theory shows that the room temperature equilibrium solid solubility of iron (Fe) in the alpha-Al matrix is extremely low (<0.03wt.%). Excessive Fe easily forms lamellar brittle intermetallic compounds (such as Al 13 Fe4、Al3Fe), which can limitedly improve the strength but significantly damage the plasticity. The non-equilibrium solidification characteristics of L-PBF provide a new path: ultrafast cooling inhibits the precipitation of equilibrium phases, promotes the existence of Fe in the form of metastable spherical nanophase (such as Al6Fe), and realizes the synergistic optimization of strength and plasticity. In terms of metal strengthening mechanism, introducing hard particles or precipitates to hinder dislocation movement is a common strengthening strategy.

[0004] The traditional precipitated strengthened aluminum alloy system (such as Al-Cu system AA2XXX, Al-Si system AA4XXX and Al-Zn system AA7XXX) faces a fundamental limitation when serving at high temperature—the strength above 200℃ significantly decreases due to the coarsening of precipitates. This phenomenon is due to the inherent interface energy of crystalline precipitates driving the Ostwald ripening mechanism, which becomes the core bottleneck restricting the high-temperature application of aluminum alloys. SUMMARY

[0005] In order to solve the above technical problems, the present application provides a laser powder bed fusion nanometer amorphous particle reinforced aluminum matrix composite material and method and application.

[0006] The first object of the present application is to provide a laser powder bed fusion nanometer amorphous particle reinforced aluminum matrix composite material.

[0007] The second object of the present application is to provide a preparation method of a laser powder bed fusion nanometer amorphous particle reinforced aluminum matrix composite material.

[0008] The third object of the present application is to provide an application method of laser powder bed fusion nanometer amorphous particle reinforced aluminum matrix composite material.

[0009] The first object of the present application can be achieved by adopting the following technical solutions:

[0010] A laser powder bed fusion nanometer amorphous particle reinforced aluminum matrix composite material is formed by stacking a plurality of fusion layers from bottom to top, each fusion layer is formed by stacking a plurality of alloy tracks in a vertical direction to the stacking direction of the fusion layers, the phase of each alloy track is composed of ultra-fine equiaxed α-Al phase and coarse columnar α-Al phase, all the ultra-fine equiaxed α-Al phases are distributed at the alloy boundaries, all the coarse columnar α-Al phases are distributed in the alloy interior, and the ultra-fine equiaxed α-Al phase and the connected coarse columnar α-Al phase form a bimodal structure; the grain boundaries of the ultra-fine equiaxed α-Al phase are dispersedly distributed with nanometer aluminum-iron-nickel amorphous particles and nanometer Mg2Si intermetallic compounds, and part of the intracrystalline distribution has nanometer Al3(Sc, Zr) particles; the nanometer aluminum-iron-nickel amorphous particles and the nanometer Mg2Si intermetallic compounds distributed in the coarse columnar α-Al phase are interconnected to form a cellular network structure; wherein the volume fraction of the nanometer aluminum-iron-nickel amorphous particles is 10-20%.

[0011] Further, the nanometer aluminum-iron-nickel amorphous particles are spherical particles with a diameter of 40-120 nm, the nanometer Al3(Sc, Zr) particles are square particles with a size of 30-60 nm, and the nanometer Mg2Si intermetallic compound is a spherical particle with a diameter of 20-60 nm.

[0012] Further, the particle size of the ultra-fine equiaxed α-Al phase is 300-500 nm; the particle size width of the coarse columnar α-Al phase is 0.5-0.8 μm, and the grain length is 0.8-1.8 μm; the particle size of a single cellular unit in the cellular network structure is 150-220 nm.

[0013] Further, the tensile strength of the laser powder bed fusion nanometer amorphous particle reinforced aluminum matrix composite material is 520-850 MPa, the elongation is 5-15%, the softening temperature is increased to 535-560℃, and the wear rate is 2.91×10 -3 ~3.29×10 - 3 mm 3 / (N·m).

[0014] The second object of the present application can be achieved by adopting the following technical solutions:

[0015] A method for laser powder bed fusion nanometer amorphous particle reinforced aluminum matrix composite material, comprising the following steps:

[0016] S1: The aluminum-iron-based alloy powder is mixed evenly in a powder mixer and then placed in the powder container of a laser powder bed melting and forming machine; wherein, the aluminum-iron-based alloy powder is mainly composed of aluminum alloy powder and iron alloy powder, the chemical composition of the aluminum alloy powder is: Mg 4.5~4.7wt.%, Er 1.2~0.6wt.%, Zr 1~0.6wt.%, Sc 0.6~0.3wt.%, with the balance being Al; the chemical composition of the iron alloy powder is: Ni 9.0~14.0wt.%, Cr 14.0~18.0wt.%, La 6.0~4.0wt.%, Nb 3.0~2.0wt.%, with the balance being Fe; the particle size of both the aluminum alloy powder and the iron alloy powder is 15~53μm, and the purity of both powders is higher than 99.9%;

[0017] S2: The substrate is loaded into the forming platform of the laser powder bed melting forming machine by means of pins, and the forming platform is adjusted to be level with the scraper; the laser powder bed melting forming chamber is evacuated and then filled with argon gas;

[0018] S3: The CAD model of the aluminum-based composite material part is sliced ​​into layers, and a series of two-dimensional scanning trajectories for laser powder bed melting are generated based on the slice contour information; according to the generated scanning trajectory, the three-dimensional solid aluminum-based composite material is deposited layer by layer on the substrate using the laser powder bed melting method.

[0019] S4: Heat treatment is performed on the aluminum-based composite material to obtain a high-strength aluminum-based composite material.

[0020] Furthermore, in step S1, the iron alloy powder accounts for 1 to 10% of the mass of the aluminum-iron composite powder.

[0021] Furthermore, the process parameters set in step S3 are as follows: laser beam power is 200~1000W, scanning speed is 500~3000mm / s, layer thickness is 25-30μm, overlap spacing is 50-80μm, and the scanning strategy adopts a path method in which the laser scanning direction rotates 67° between two consecutive layers.

[0022] Furthermore, in step S3, by adjusting the laser powder bed melting process parameters, a high cooling rate is generated, and the key elements introduced by the iron alloy powder work together with the aluminum alloy elements, so that the alloy composition in the local component enrichment area meets the conditions for high glass-forming ability, thereby controlling the production of in-situ nano-aluminum-iron-nickel amorphous particles with a high volume fraction.

[0023] The key elements are iron, chromium, nickel, niobium, etc., and the alloy composition is aluminum, iron, nickel, etc.

[0024] Furthermore, the substrate is an aluminum alloy.

[0025] Furthermore, the heat treatment in step S4 is as follows: the aluminum-based composite material is annealed at 300~450℃.

[0026] The third objective of this invention can be achieved by adopting the following technical solution:

[0027] An application method for laser-fused nano-amorphous particle-reinforced aluminum matrix composites, based on the above-mentioned laser-fused nano-amorphous particle-reinforced aluminum matrix composites or laser-fused nano-amorphous particle-reinforced aluminum matrix composites prepared by the above-mentioned method, in the fields of aviation, aerospace vehicles and other technologies.

[0028] The present invention has the following advantages over the prior art:

[0029] (1) The laser powder bed fused nano-amorphous particle reinforced aluminum matrix composite material provided by the present invention is composed of multiple fused layers stacked sequentially from bottom to top. Each fused layer is composed of multiple alloys stacked sequentially in a direction perpendicular to the direction of stacking the fused layers. The phase of each alloy consists of ultrafine equiaxed α-Al phase and coarse columnar α-Al phase. All ultrafine equiaxed α-Al phases are distributed at the alloy boundary, and all coarse columnar α-Al phases are distributed inside the alloy. The ultrafine equiaxed α-Al phase and the connected coarse columnar α-Al phase form a bimodal structure. Nano-aluminum-iron-nickel amorphous particles and nano-Mg2Si intermetallic compounds are dispersed on the grain boundaries of the ultrafine equiaxed α-Al phase, and nano-Al3(Sc,Zr) particles are distributed in some of the grains. The nano-aluminum-iron-nickel amorphous particles and nano-Mg2Si intermetallic compounds distributed in the coarse columnar α-Al phase are interconnected to form a cellular network structure. The volume fraction of nano-aluminum-iron-nickel amorphous particles is 10~20%. The heterogeneous structure formed by these microscopic features gives the nano-amorphous particle-reinforced aluminum matrix composite material ultra-high strength, good ductility, excellent thermal stability and wear resistance.

[0030] (2) The laser powder bed fused nano-amorphous particle reinforced aluminum matrix composite material provided by the present invention has excellent mechanical and tribological properties: Printed state: ultimate tensile strength reaches 520~720MPa, elongation 8~15%, Vickers hardness 141~186HV, and wear rate is reduced by 20~30% compared with the matrix aluminum alloy; Heat treated state: ultimate tensile strength is significantly increased to 650-850MPa, elongation 5~10%, Vickers hardness 172~208HV, softening temperature is increased to 530~560℃, and wear rate is further reduced by 30~50%.

[0031] (3) The method provided by this invention, by precisely controlling the laser powder bed melting process parameters (generating local high temperature gradients and ultrafast cooling rates), and combining the synergistic effect of key elements (Ni, Cr, La, Nb) in the introduced iron alloy powder with aluminum alloy elements (Al, Fe, Er), satisfies the high glass-forming ability conditions in the local component-enriched region of the molten pool, successfully generating high volume fraction (>10%) nano-aluminum-iron-nickel amorphous particles in the aluminum matrix in situ. Utilizing the unique disordered structure, ultra-high intrinsic strength, and multiple shear band deformation mechanism constrained at the nanoscale of the nano-amorphous particles, a synergistic improvement in material strength and plasticity is achieved. In addition, the excellent high hardness and thermal stability inherent in the amorphous phase significantly improve the overall performance of the composite material. Attached Figure Description

[0032] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0033] Figure 1 This is a schematic diagram of the microstructure of the nano-amorphous particle-reinforced aluminum matrix composite material of Example 1 of the present invention. Detailed Implementation

[0034] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the present invention will be clearly and completely described below in conjunction with the embodiments. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention. It should be understood that the specific embodiments described are merely used to explain this application and are not intended to limit this application. Example 1:

[0035] The method for laser-driven powder bed melting of nano-amorphous particles to reinforce aluminum matrix composites provided in this embodiment includes the following steps:

[0036] S1: The aluminum-iron alloy powder is mixed evenly in a powder mixer and then placed in the powder container of a laser powder bed melting and forming machine. The aluminum-iron alloy powder is mainly composed of aluminum alloy powder and iron alloy powder. The chemical composition of the aluminum alloy powder is: Mg 4.5~4.7wt.%, Er 0.6~1.2wt.%, Zr 0.6~1wt.%, Sc 0.3~0.6wt.%, with the balance being Al. The chemical composition of the iron alloy powder is: Ni 14.0~9.0wt.%, Cr 18.0~14.0wt.%, La 4.0~6.0wt.%, Nb 2.0~3.0wt.%, with the balance being Fe. The particle size of both the aluminum alloy powder and the iron alloy powder is 15~53μm, and the purity of both powders is higher than 99.9%.

[0037] S2: Insert the 100x100mm substrate into the forming platform of the laser powder bed melting forming machine using pins, and adjust the forming platform to be level with the scraper; evacuate the laser powder bed melting forming chamber to a vacuum, and then fill it with argon gas;

[0038] S3: Slice the CAD model of the aluminum-based composite material part into layers, and generate a series of two-dimensional scanning trajectories for laser powder bed melting based on the slice contour information; according to the generated scanning trajectory, use the laser powder bed melting method to build up the three-dimensional solid aluminum-based composite material layer by layer.

[0039] S4: The formed aluminum-based composite material is cut off using a wire EDM machine, and the aluminum-based composite material is heat-treated. Then, the phase, microstructure and composition of the samples before and after treatment are analyzed, and then the tensile strength is tested.

[0040] Furthermore, in step S1, the proportion of iron alloy powder in the aluminum-iron composite powder is 1 wt.%.

[0041] Further, before step S2, the substrate is milled to a flat surface and then sandblasted; it is then ultrasonically cleaned with anhydrous ethanol and dried in a vacuum drying oven. The substrate is 6061 aluminum alloy.

[0042] Furthermore, in step S3, the laser beam power, scanning rate, layer thickness, overlap spacing, and scanning strategy are adjusted. The laser beam power is 1000W, the scanning speed is 3000mm / s, the layer thickness is 25μm, the overlap spacing is 50μm, and the scanning strategy adopts a path method in which the laser scanning direction rotates 67° between two consecutive layers.

[0043] Furthermore, the heat treatment in step S4 is as follows: the aluminum-based alloy is annealed at 300°C for 4 hours.

[0044] The bulk nanocrystalline amorphous particle reinforced aluminum matrix composite material prepared by the above method can be referred to Figure 1Its phases are mainly composed of α-Al phase, aluminum-iron-nickel amorphous phase, and two intermetallic compounds, Al3(Sc,Zr) and Mg2Si. Among them, ultrafine equiaxed α-Al and coarse columnar α-Al form a bimodal structure. Nanoscale aluminum-iron-nickel amorphous particles and nanoscale Mg2Si intermetallic compounds are dispersed on the grain boundaries of ultrafine equiaxed α-Al, with sizes of 40~120nm and 20~60nm, respectively. Nanoscale Al3(Sc,Zr) particles with a size of 30~60nm are present within the grains. In the coarse columnar α-Al matrix, nanoscale aluminum-iron-nickel amorphous particles and nanoscale Mg2Si have a surrounding and interconnected cellular network structure.

[0045] The equiaxed α-Al phase has an average grain size of 500 nm, the columnar α-Al phase has a grain width of 0.5–0.8 μm and a grain length of 0.8–1.8 μm, and the cellular units surrounded by aluminum-iron-nickel amorphous and Mg2Si have an average size of 220 nm and a volume fraction of 10%. After heat treatment, nano-Al3(Sc,Zr,Er) intermetallic compounds precipitate in the α-Al matrix, further improving the strength of the material.

[0046] After testing, the aluminum-based composite material showed an ultimate tensile strength of 520 MPa, an elongation of 15%, and a wear rate of 3.27 × 10⁻⁶. -3 mm 3 / (N·m); after heat treatment, the ultimate tensile strength is 650MPa, the elongation reaches 10%, and the wear rate is 4.14×10. -3 mm 3 / (N·m); Compared with the base aluminum alloy, its softening temperature is increased by 35℃ and the wear rate is reduced by 20.59~33.22%. Example 2:

[0047] The method for laser-driven powder bed melting of nano-amorphous particles to reinforce aluminum matrix composites provided in this embodiment includes the following steps:

[0048] S1: The aluminum-iron alloy powder is mixed evenly in a powder mixer and then placed in the powder container of a laser powder bed melting and forming machine. The aluminum-iron alloy powder is mainly composed of aluminum alloy powder and iron alloy powder. The chemical composition of the aluminum alloy powder is: Mg 4.5~4.7wt.%, Er 0.6~1.2wt.%, Zr 0.6~1wt.%, Sc 0.3~0.6wt.%, with the balance being Al. The chemical composition of the iron alloy powder is: Ni 14.0~9.0wt.%, Cr 18.0~14.0wt.%, La 4.0~6.0wt.%, Nb 2.0~3.0wt.%, with the balance being Fe. The particle size of both the aluminum alloy powder and the iron alloy powder is 15~53μm, and the purity of both powders is higher than 99.9%.

[0049] S2: Insert the 100x100mm substrate into the forming platform of the laser powder bed melting forming machine using pins, and adjust the forming platform to be level with the scraper; evacuate the laser powder bed melting forming chamber to a vacuum, and then fill it with argon gas;

[0050] S3: Slice the CAD model of the aluminum-based composite material part into layers, and generate a series of two-dimensional scanning trajectories for laser powder bed melting based on the slice contour information; according to the generated scanning trajectory, use the laser powder bed melting method to build up the three-dimensional solid aluminum-based composite material layer by layer.

[0051] S4: The formed aluminum-based composite material is cut off using a wire EDM machine, and the aluminum-based composite material is heat-treated. Then, the phase, microstructure and composition of the samples before and after treatment are analyzed, and then the tensile strength is tested.

[0052] Furthermore, in step S1, the proportion of iron alloy powder in the aluminum-iron composite powder is 5 wt.%.

[0053] Further, before step S2, the substrate is milled to a flat surface and then sandblasted; it is then ultrasonically cleaned with anhydrous ethanol and dried in a vacuum drying oven. The substrate is 6061 aluminum alloy.

[0054] Furthermore, in step S3, the laser beam power, scanning rate, layer thickness, overlap spacing, and scanning strategy are adjusted. The laser beam power is 500W, the scanning speed is 1500mm / s, the layer thickness is 30μm, the overlap spacing is 70μm, and the scanning strategy adopts a path method in which the laser scanning direction rotates 67° between two consecutive layers.

[0055] Furthermore, the heat treatment in step S4 is as follows: the aluminum-based alloy is annealed at 375°C for 4 hours.

[0056] The bulk nanocrystalline amorphous particle-reinforced aluminum matrix composite material prepared by the above method mainly consists of α-Al phase, aluminum-iron-nickel amorphous phase, and two intermetallic compounds, Al3(Sc,Zr) and Mg2Si. The ultrafine equiaxed α-Al and coarse columnar α-Al form a bimodal structure. Nanocrystalline aluminum-iron-nickel amorphous particles and nanocrystalline Mg2Si intermetallic compounds are dispersed along the grain boundaries of the ultrafine equiaxed α-Al, with sizes of 40–120 nm and 20–60 nm, respectively. Nanocrystalline Al3(Sc,Zr) particles with a size of 30–60 nm are present within the grains. Within the coarse columnar α-Al matrix, the nanocrystalline aluminum-iron-nickel amorphous particles and nanocrystalline Mg2Si form a surrounding and interconnected cellular network structure.

[0057] The equiaxed α-Al phase has an average grain size of 400 nm, the columnar α-Al phase has a grain width of 0.5–0.8 μm and a grain length of 0.8–1.8 μm, and the cellular units surrounded by aluminum-iron-nickel amorphous and Mg2Si have an average size of 180 nm and a volume fraction of 15%. After heat treatment, nano-Al3(Sc,Zr,Er) intermetallic compounds precipitate in the α-Al matrix, further improving the strength of the material.

[0058] Testing revealed that the aluminum-based composite material exhibited an ultimate tensile strength of 630 MPa, an elongation of 12%, a softening temperature increased by 40°C, and a wear rate of 3.24 × 10⁻⁶. -3 mm 3 / (N·m); After heat treatment, the ultimate tensile strength reaches 750MPa, the elongation reaches 8%, and the wear rate is 3.09×10⁻⁶. -3 mm 3 / (N·m); Compared with the base aluminum alloy, its softening temperature is increased by 45℃ and the wear rate is reduced by 21.32~50.07%. Example 3:

[0059] The laser powder bed melting method for reinforcing aluminum matrix composites with nano-amorphous particles provided in this embodiment includes the following steps:

[0060] S1: The aluminum-iron alloy powder is mixed evenly in a powder mixer and then placed in the powder container of a laser powder bed melting and forming machine. The aluminum-iron alloy powder is mainly composed of aluminum alloy powder and iron alloy powder. The chemical composition of the aluminum alloy powder is: Mg 4.5~4.7wt.%, Er 0.6~1.2wt.%, Zr 0.6~1wt.%, Sc 0.3~0.6wt.%, with the balance being Al. The chemical composition of the iron alloy powder is: Ni 14.0~9.0wt.%, Cr 18.0~14.0wt.%, La 4.0~6.0wt.%, Nb 2.0~3.0wt.%, with the balance being Fe. The particle size of both the aluminum alloy powder and the iron alloy powder is 15~53μm, and the purity of both powders is higher than 99.9%.

[0061] S2: Insert the 100x100mm substrate into the forming platform of the laser powder bed melting forming machine using pins, and adjust the forming platform to be level with the scraper; evacuate the laser powder bed melting forming chamber to a vacuum, and then fill it with argon gas;

[0062] S3: Slice the CAD model of the aluminum-based composite material part into layers, and generate a series of two-dimensional scanning trajectories for laser powder bed melting based on the slice contour information; according to the generated scanning trajectory, use the laser powder bed melting method to build up the three-dimensional solid aluminum-based composite material layer by layer.

[0063] S4: The formed aluminum-based composite material is cut off using a wire EDM machine, and the aluminum-based composite material is heat-treated. Then, the phase, microstructure and composition of the samples before and after treatment are analyzed, and then the tensile strength is tested.

[0064] Furthermore, in step S1, the proportion of iron alloy powder in the aluminum-iron composite powder is 10 wt.%.

[0065] Further, before step S2, the substrate is milled to a flat surface and then sandblasted; it is then ultrasonically cleaned with anhydrous ethanol and dried in a vacuum drying oven. The substrate is a 6061 aluminum alloy.

[0066] Furthermore, in step S3, the laser beam power, scanning rate, layer thickness, overlap spacing, and scanning strategy are adjusted. The laser beam power is 200W, the scanning speed is 500mm / s, the layer thickness is 30μm, the overlap spacing is 80μm, and the scanning strategy adopts a path method in which the laser scanning direction rotates 67° between two consecutive layers.

[0067] Furthermore, the heat treatment in step S4 is as follows: the aluminum-based alloy is annealed at 450°C for 4 hours.

[0068] The bulk nano-amorphous particle-reinforced aluminum matrix composite material prepared by the above method mainly consists of α-Al phase, aluminum-iron-nickel amorphous phase, Al3(Sc,Zr) and two intermetallic compounds, Mg2Si. Among them, ultrafine equiaxed α-Al and coarse columnar α-Al form a bimodal structure. Nano-amorphous aluminum-iron-nickel particles and nano-Mg2Si intermetallic compounds are dispersed on the grain boundaries of ultrafine equiaxed α-Al, with sizes of 40~120nm and 20~60nm, respectively. Nano-Al3(Sc,Zr) particles with a size of 30~60nm are present in the grain. In the coarse columnar α-Al matrix, nano-amorphous aluminum-iron-nickel particles and nano-Mg2Si have a surrounding and interconnected cellular network structure.

[0069] The equiaxed α-Al phase has an average grain size of 300 nm, the columnar α-Al phase has a grain width of 0.5–0.8 μm and a grain length of 0.8–1.8 μm, and the cellular units surrounded by aluminum-iron-nickel amorphous and Mg2Si have an average size of 150 nm and a volume fraction of 20%. After heat treatment, nano-Al3(Sc,Zr,Er) intermetallic compounds precipitate in the α-Al matrix, further improving the strength of the material.

[0070] Testing revealed that the aluminum-based composite material exhibited an ultimate tensile strength of 720 MPa, an elongation of 8%, a softening temperature increased by 60°C, and a wear rate of 2.92 × 10⁻⁶. -3 mm 3 / (N·m); After heat treatment, the ultimate tensile strength reaches 850MPa, the elongation reaches 5%, and the wear rate is 2.91×10⁻⁶. -3 mm 3 / (N·m); Compared with the base aluminum alloy, its softening temperature is increased by 60℃ and the wear rate is reduced by 29.19~53.10%.

[0071] In summary, this invention innovatively employs L-PBF technology to successfully construct a high volume fraction (10-20 vol.%) of nano-amorphous particle reinforcing phase within an aluminum matrix, overcoming the difficulties faced by traditional crystalline precipitates through an innovative mechanism. By rationally designing the composition and controlling process parameters, the rapid solidification of excess Fe inhibits the precipitation of the brittle equilibrium phase. The resulting amorphous phase absorbs crack energy through multiple shear band deformation, achieving ultra-high strength and excellent ductility at room temperature. Simultaneously, the amorphous phase avoids Ostwald ripening dominated by grain boundary diffusion, eliminating the coarsening path dominated by grain boundary diffusion and improving the thermal stability of the aluminum alloy. This invention is the first to achieve additive manufacturing of bulk aluminum-based amorphous composite materials, providing a transformative solution for high-strength aluminum-based composite materials in aerospace and other transportation applications, and opening a new paradigm for the design of amorphous composite materials with controllable "composition-process-structure".

[0072] The above embodiments are preferred embodiments of the present invention, but the embodiments of the present invention are not limited to the above embodiments. Any changes, modifications, substitutions, combinations, or simplifications made without departing from the spirit and principle of the present invention shall be considered equivalent substitutions and shall be included within the protection scope of the present invention.

Claims

1. A laser-fused powder bed molten nanoparticle-reinforced aluminum matrix composite material, characterized in that, It is composed of multiple molten layers stacked sequentially from bottom to top. Each molten layer is composed of multiple alloy layers stacked sequentially in a direction perpendicular to the direction of stacking the molten layers. The phase composition of each alloy layer consists of ultrafine equiaxed α-Al phase and coarse columnar α-Al phase. All ultrafine equiaxed α-Al phases are distributed at the alloy boundaries, and all coarse columnar α-Al phases are distributed inside the alloy. The ultrafine equiaxed α-Al phase and the connected coarse columnar α-Al phase form a bimodal structure. Nano-sized aluminum-iron-nickel amorphous particles and nano-sized Mg2Si intermetallic compounds are dispersed on the grain boundaries of the ultrafine equiaxed α-Al phase, and nano-sized Al3(Sc,Zr) particles are distributed in some of the grains. The coarse columnar α-Al phase is distributed within... Nano-sized aluminum-iron-nickel amorphous particles and nano-sized Mg2Si intermetallic compounds are interconnected to form a cellular network structure; wherein, the nano-sized aluminum-iron-nickel amorphous particles are spherical particles with a diameter of 40~120nm, the nano-sized Al3(Sc,Zr) particles are square particles with a size of 30~60nm, the nano-sized Mg2Si intermetallic compounds are spherical particles with a diameter of 20~60nm, the ultrafine equiaxed α-Al phase has a particle size of 300~500nm, the coarse columnar α-Al phase has a particle width of 0.5~0.8μm and a grain length of 0.8~1.8μm, and the volume fraction of the nano-sized aluminum-iron-nickel amorphous particles is 10~20%.

2. The laser-fused powder bed molten nanoparticle-reinforced aluminum matrix composite material according to claim 1, characterized in that, The particle size of a single cellular unit in the cellular network structure is 150~220 nm.

3. The laser-fused powder bed molten nanoparticle-reinforced aluminum matrix composite material according to any one of claims 1 to 2, characterized in that, The laser-fused amorphous nanoparticle-reinforced aluminum matrix composite material has a tensile strength of 520~850MPa, an elongation of 5~15%, a softening temperature of 535~560℃, and an abrasion rate of 2.91×10⁻⁶. -3 ~3.29×10 -3 mm 3 / (N·m).

4. A method for preparing a laser-fused amorphous nanoparticle-reinforced aluminum matrix composite material according to any one of claims 1 to 3, characterized in that, Includes the following steps: S1: The aluminum-iron-based alloy powder is mixed evenly in a powder mixer and then placed in the powder container of a laser powder bed melting and forming machine; wherein, the aluminum-iron-based alloy powder is mainly composed of aluminum alloy powder and iron alloy powder, the chemical composition of the aluminum alloy powder is: Mg 4.5~4.7wt.%, Er 1.2~0.6wt.%, Zr 1~0.6wt.%, Sc 0.6~0.3wt.%, with the balance being Al; the chemical composition of the iron alloy powder is: Ni 9.0~14.0wt.%, Cr 14.0~18.0wt.%, La 6.0~4.0wt.%, Nb 3.0~2.0wt.%, with the balance being Fe; the particle size of both the aluminum alloy powder and the iron alloy powder is 15~53μm, and the purity of both powders is higher than 99.9%; S2: The substrate is loaded into the forming platform of the laser powder bed melting forming machine by means of pins, and the forming platform is adjusted to be level with the scraper; the laser powder bed melting forming chamber is evacuated and then filled with argon gas; S3: The CAD model of the aluminum-based composite material part is sliced ​​into layers, and a series of two-dimensional scanning trajectories for laser powder bed melting are generated based on the slice contour information; according to the generated scanning trajectory, the three-dimensional solid aluminum-based composite material is deposited layer by layer on the substrate using the laser powder bed melting method. S4: Heat treatment is performed on the aluminum-based composite material to obtain a high-strength aluminum-based composite material.

5. The method according to claim 4, characterized in that, In step S1, the iron alloy powder accounts for 1 to 10% of the mass of the aluminum-iron composite powder.

6. The method according to claim 4, characterized in that, The process parameters set in step S3 are as follows: laser beam power is 200~1000W, scanning speed is 500~3000mm / s, layer thickness is 25-30μm, overlap spacing is 50-80μm, and the scanning strategy adopts a path method in which the laser scanning direction rotates 67° between two consecutive layers.

7. The method according to any one of claims 4 to 6, characterized in that, In step S3, by adjusting the laser powder bed melting process parameters, a high cooling rate is generated, and the key elements introduced by the iron alloy powder work together with the aluminum alloy elements, so that the alloy composition in the local component enrichment area meets the conditions for high glass forming ability, thereby controlling the production of in-situ nano-aluminum-iron-nickel amorphous particles with a high volume fraction.

8. The method according to any one of claims 4 to 6, characterized in that, The heat treatment in step S4 is to anneal the aluminum-based composite material at 300~450℃.

9. A method for applying a laser-fused powder bed nanoparticle-reinforced aluminum matrix composite material, characterized in that, Applications of laser-bonded powder bed fused nano-amorphous particle reinforced aluminum matrix composites according to any one of claims 1 to 3 or laser-bonded powder bed fused nano-amorphous particle reinforced aluminum matrix composites prepared according to any one of claims 4 to 8 in the field of aviation and aerospace vehicle technology.

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