High-entropy alloy particle reinforced laminated structure aluminum matrix composite material and preparation process thereof

Abstract

This invention discloses a layered aluminum matrix composite material reinforced with high-entropy alloy particles and its preparation process. The high-entropy alloys include FeCoCrNi, FeCoMnNi, AlFeCoCrNi, and AlTi series, while the aluminum alloys include AlSi10Mg, AlSi12, and AlSi7Mg. First, based on laser selective melting forming technology, aluminum alloy powder is printed into a layered topological framework. Then, high-entropy alloy powder is filled into the layered framework to obtain a preform. Finally, using pressure infiltration technology, taking advantage of the natural wettability of the high-entropy alloy and the aluminum alloy matrix, molten aluminum alloy is pressure-infiltrated into the preform, resulting in a layered high-entropy alloy particle-reinforced aluminum matrix composite material. The concept of this invention originates from the multilayered structure of seashells. The prepared material exhibits high density, good strength and toughness, and high interfacial bonding strength. Furthermore, the novel preparation method demonstrates promising application prospects.

Description

Technical Field

[0001] This invention belongs to the field of metal matrix composites, specifically relating to a layered aluminum matrix composite material reinforced with high-entropy alloy particles and its preparation process. Background Technology

[0002] In recent years, aluminum matrix composites and their reinforcing phases have become a research hotspot. Many researchers have considered using metallic particles such as elemental metals, quasicrystalline materials, and amorphous alloys as reinforcing materials for aluminum alloys to improve the interface between the reinforcing particles and the aluminum alloy matrix. High-entropy alloys, as a novel alloy material, possess characteristics such as high strength, high hardness, and good high-temperature stability, while also exhibiting good wettability and compatibility with aluminum alloys, making them very suitable as reinforcing phases for aluminum alloys.

[0003] The nacreous layer of seashells possesses a layered biological structure, with overlapping calcium carbonate aragonite flakes in its microstructure. The tensile strength of nacre is more than twice that of calcium carbonate, and its fracture toughness is three thousand times greater, perfectly achieving the goal of simultaneously improving strength and toughness. Addressing the common issue of a significant decrease in plasticity when increasing the strength of aluminum-based composites, mimicking the layered structure of nacre can achieve a breakthrough in its comprehensive mechanical properties.

[0004] This invention utilizes selective laser melting (SLM) technology to print layered aluminum alloy frames, solving the manufacturing challenges of complex structures such as porous, hollow, and lattice-shaped parts that are difficult to manufacture using traditional techniques. This technology precisely controls the thickness and shape of each layer of the printed material, thereby accurately producing layered materials with specific dimensions and structures. These layered materials exhibit high density, strong interlayer bonding, and excellent mechanical properties. Furthermore, they offer high design freedom, flexible printing parameter adjustment, and rapid and convenient molding, opening up broad prospects for the innovative design and manufacturing of high-performance products.

[0005] Currently, there are no reports on using high-entropy alloys as reinforcing phases and employing laser selective melting forming technology to prepare layered aluminum matrix composites. Summary of the Invention

[0006] This invention provides a layered aluminum matrix composite material reinforced with high-entropy alloy particles and its preparation process. The method uses aluminum-silicon alloy powder to print an alloy framework with a layered structure; utilizing the good fluidity of the bulk molten alloy, molten aluminum alloy liquid is extruded into the aluminum alloy framework filled with high-entropy alloy powder; utilizing the natural interfacial wettability between the high-entropy alloy and the aluminum alloy matrix, it serves as the reinforcing phase of the aluminum matrix composite material; the layered aluminum matrix composite material of this invention possesses comprehensive properties such as high strength and high toughness.

[0007] This invention is implemented according to the following steps:

[0008] (1) Aluminum alloy frame design and SLM (Selective Laser Melting, SLM) printing: First, design layered topological structure frames with different shapes, sizes and thicknesses; then, load vacuum-dried aluminum alloy powder into the printer powder supply hopper, spread the powder evenly in the printer powder spreading hopper, adjust the printing parameters according to the two-dimensional slices of the three-dimensional model input by the printer, and print after printing. After printing is completed, aluminum alloy layered topological structure frames are obtained.

[0009] (2) Preform preparation: First, high-entropy alloy powder is tightly and uniformly filled into the aluminum alloy topology framework obtained in step (1) to obtain a preform. Then, the preform is fixed as a whole in a cylindrical graphite groove with suitable size and built-in holes. The graphite groove and the preform cooperate with each other.

[0010] (3) Aluminum alloy melting and preform preheating: Weigh a certain mass of aluminum alloy, put it into a melting furnace, heat, melt, hold, and refine it to obtain aluminum alloy melt. Put the preform obtained in step (2) together with the graphite mold into a steel mold, heat and hold.

[0011] (4) Preparation of layered aluminum matrix composite material: The aluminum alloy melt obtained in step (3) is cast into a steel mold using a hydraulic press, and then pressure infiltration is performed. After the aluminum alloy melt is completely penetrated into the preform under pressure, it is cooled and solidified to obtain a layered aluminum matrix composite material reinforced with high entropy alloy particles.

[0012] In the above method, the layered topological structure framework designed in step (1) includes various polygons, such as triangles, quadrilaterals, hexagons, etc., with a side length range of 1mm-10mm and a thickness range of 0.1mm-1mm.

[0013] In the above method, in step (1), the selected aluminum alloy powder is mainly an Al-Si alloy suitable for selective laser melting (SLM) technology. The main materials include AlSi10Mg, AlSi12, AlSi7Mg, etc. The particle size of the aluminum alloy powder ranges from 10 to 100 μm, and the purity ranges from 99% to 99.99%.

[0014] In the above method, in step (1), aluminum alloy powder is placed in a vacuum drying oven and heated to 60-100℃, and then kept warm and dried for 2-10 hours.

[0015] In the above method, the printing parameters of the layered structure frame in step (1) are: laser power of 200-400W, scanning speed of 1100-1400mm / s, scanning strategy of laser scanning direction of adjacent two layers at 60°-70°, scanning distance of 100-150μm, and powder layer thickness of 10-100μm.

[0016] In the above method, the high-entropy alloy powder selected in step (2) includes FeCoCrNi, FeCoMnNi, AlFeCoCrNi, and AlTi series powders. The particle size range of the high-entropy alloy powder is 10-100 μm, and the purity range is 99% to 99.99%.

[0017] In the above method, the holes in the cylindrical graphite groove in step (2) are circular with a diameter of 0.1-2 mm.

[0018] In the above method, the composition of the aluminum alloy block in step (3) is consistent with or similar to the composition of the aluminum alloy powder in step (1).

[0019] In the above method, the mass of aluminum alloy in step (3) is 3-10 times the mass of the preform.

[0020] In the above method, in step (3), the aluminum alloy block is heated to 100-300°C above its melting point at a heating rate of 5-10°C / min, and held for 0.5-4 hours.

[0021] In the above method, the heating temperature of the preform in step (3) is 200-600℃, and the heat is maintained for 2-4 hours.

[0022] In the above method, the pressure in step (4) during pressure impregnation is set to 40-120 MPa, the pressure holding time is set to 2-15 min, and the cooling time is set to 2-15 min.

[0023] The principle of this invention:

[0024] This invention mimics the nacreous structure of seashells in nature, designing a multi-layered aluminum alloy frame with a topological structure. Hard, high-entropy alloy particles are fixed as reinforcing phase particles within the aluminum alloy frame structure, achieving an alternating effect of strength and plasticity. This breaks through the strength-plasticity "bottleneck" of conventional homogeneous particle-reinforced aluminum matrix composites. Simultaneously, the layered aluminum matrix composite material prepared by the liquid process has high density and is suitable for use as a structural or functional / structural material.

[0025] Technical features and advantages of the present invention:

[0026] 1. This invention utilizes laser selective melting forming technology to prepare layered aluminum alloy frames of different shapes, sizes, and thicknesses. The resulting frames have low surface roughness and a density of up to 99%. Furthermore, different types of high-entropy alloy powders can be selected to fill the frames to form preforms. The process is flexible and suitable for industrial production and application.

[0027] 2. This invention utilizes pressure infiltration technology, enabling rapid molding and avoiding casting defects such as shrinkage cavities, porosity, and gas bubbles that occur in gravity casting processes. It also inhibits the formation of harmful interfacial reaction products. Under pressure, molten aluminum can completely penetrate the high-entropy alloy powder, resulting in a material with high density and excellent interfacial bonding.

[0028] 3. This invention utilizes the natural interfacial wettability between high-entropy alloys and aluminum alloy matrices, using high-entropy alloy particles as reinforcements for aluminum-based composite materials, thereby further improving the interfacial bonding strength; at the same time, different types of high-entropy alloys can also be selected to meet the performance requirements of composite materials under different service conditions. Attached Figure Description

[0029] Figure 1 The diagrams show different features of the aluminum alloy frames formed by SLM in Examples 1, 4, and 7.

[0030] Figure 2 This is a preform diagram of Example 1.

[0031] Figure 3 This is a picture of the finished product of the layered aluminum matrix composite material obtained after pressure impregnation of the preform in Example 1.

[0032] Figure 4 The image shows the low-magnification microstructure of the layered aluminum matrix composite material reinforced with high-entropy alloy particles in Example 2.

[0033] Figure 5 The image shows the high-magnification microstructure of the layered aluminum matrix composite material reinforced with high-entropy alloy particles in Example 2.

[0034] Figure 6 The image shows the compressive stress-strain curve of the layered aluminum matrix composite material reinforced with high-entropy alloy particles in Example 2. Detailed Implementation

[0035] The present invention will be further described in detail below with reference to specific embodiments, but the implementation of the present invention is not limited thereto. For process parameters not specifically noted, conventional techniques can be referred to.

[0036] Example 1

[0037] (1) Aluminum alloy frame design and SLM printing: First, a rectangular structure with a thickness of 0.2 mm and a single frame length and width of 2 × 1 mm was designed. Then, AlSi10Mg alloy powder, which had been kept at 60℃ for 6 hours under vacuum, was placed into the printer's powder supply hopper. The printer's laser power was set to 350W, the scanning speed to 1100 mm / s, the scanning strategy to have the laser scanning directions of adjacent layers at 67°, the scanning interval to 150 μm, and the powder layer thickness to 30 μm. (The alloy powder particle size and powder layer thickness were similar.) The printed frame is shown below. Figure 1 As shown.

[0038] (2) Preform preparation: First, Fe 25 Co 25 Cr 25 Ni 25 High-entropy alloy powder is densely and uniformly filled into the AlSi10Mg aluminum alloy topological framework to obtain a preform. The preform is then fixed as a whole into a cylindrical graphite groove with built-in holes. The graphite groove and the preform fit together perfectly; the holes in the groove are circular with a diameter of 0.2 mm. (See diagram of the preform.) Figure 2 As shown.

[0039] (3) Aluminum alloy melting and preheating of preform: Weigh AlSi10Mg block with a mass three times that of the preform, put it into the melting furnace and heat it at 10℃ / min to 300℃ above its melting point and hold it for 4h to obtain aluminum alloy melt; put the preform together with the graphite mold into the steel mold, heat the preform to 370℃ and hold it for 3h.

[0040] (4) Preparation of layered aluminum matrix composite material: Molten aluminum alloy was poured into a steel mold using a hydraulic press, followed by pressure infiltration. After the molten aluminum alloy completely penetrated the preform under pressure, solidification and cooling yielded a layered aluminum matrix composite material reinforced with high-entropy alloy particles. The pressure infiltration was set to 70 MPa, the holding time to 3 min, and the cooling time to 5 min. The finished layered aluminum matrix composite material obtained after pressure infiltration of the preform is shown below. Figure 3 As shown.

[0041] Example 2

[0042] (1) Aluminum alloy frame design and SLM printing: First, a rectangular structure with a thickness of 0.4 mm and a single frame length and width of 6 × 3 mm was designed. Then, AlSi10Mg alloy powder, which had been kept at 70℃ for 7 hours under vacuum, was placed into the printer's powder supply hopper. The printer's laser power was set to 355W, the scanning speed to 1200 mm / s, the scanning strategy to have the laser scanning directions of adjacent layers at 70°, the scanning interval to 100 μm, and the powder layer thickness to 40 μm. (The alloy powder particle size and powder layer thickness were similar.)

[0043] (2) Preform preparation: First, Al 10 (Fe 25 Co 25 Cr 25 Ni 25 ) 90 High-entropy alloy powder is densely and uniformly filled into the AlSi10Mg aluminum alloy topological structure framework to obtain a preform; then the preform is fixed as a whole in a cylindrical graphite groove with its own holes. The graphite groove and the preform cooperate with each other. The holes in the groove are circular with a diameter of 0.3mm.

[0044] (3) Aluminum alloy melting and preheating of preform: Weigh AlSi10Mg block with a mass of 4 times that of preform, put it into the melting furnace and heat it. After heating to the melting temperature of 265℃ at 8℃ / min, hold it for 3.5h to obtain aluminum alloy melt. Put the preform together with the graphite mold into the steel mold, heat the preform to 330℃ and hold it for 4h.

[0045] (4) Preparation of layered aluminum matrix composite material: Molten aluminum alloy was poured into a steel mold using a hydraulic press, followed by pressure infiltration. After the molten aluminum alloy completely penetrated the preform under pressure, it cooled and solidified to obtain a layered aluminum matrix composite material reinforced with high-entropy alloy particles. The pressure infiltration was set to 75 MPa, and the holding time was set to 6 min. The cooling time was also set to 6 min. The low-magnification and high-magnification microstructure morphologies of the layered aluminum matrix composite material are shown below. Figure 4 , Figure 5 As shown. Mechanical properties are as follows. Figure 6 As shown.

[0046] Example 3

[0047] (1) Aluminum alloy frame design and SLM printing: First, a rectangular structure with a thickness of 0.3 mm and a single frame length and width of 4 × 2 mm was designed. Then, AlSi10Mg alloy powder, which had been kept at 100℃ for 8 hours under vacuum, was placed into the printer's powder supply hopper. The printer's laser power was set to 390W, the scanning speed to 1150 mm / s, the scanning strategy to have the laser scanning directions of adjacent layers at 78°, the scanning interval to 120 μm, and the powder layer thickness to 45 μm. (The alloy powder particle size and powder layer thickness were similar.)

[0048] (2) Preform preparation: First, Fe 20 Co 20 Cr 20 Ni 20 Mn 20High-entropy alloy powder is densely and uniformly filled into the AlSi10Mg aluminum alloy topological structure framework to obtain a preform; then the preform is fixed as a whole in a cylindrical graphite groove with its own holes. The graphite groove and the preform cooperate with each other. The holes in the groove are circular with a diameter of 0.4mm.

[0049] (3) Aluminum alloy melting and preheating of preform: Weigh AlSi10Mg block with a mass of 5 times that of preform, put it into the melting furnace and heat it. The temperature is raised to 200℃ at 5℃ / min and then held for 1.5h to obtain aluminum alloy melt. Put the preform together with the graphite mold into the steel mold, heat the preform to 350℃ and hold for 2.5h.

[0050] (4) Preparation of layered aluminum matrix composite material: Molten aluminum alloy was poured into a steel mold using a hydraulic press, followed by pressure infiltration. After the molten aluminum alloy completely penetrated the preform under pressure, it cooled and solidified to obtain a layered aluminum matrix composite material reinforced with high-entropy alloy particles. The pressure was set to 80 MPa, and the holding time was set to 7 min. The cooling time was also set to 7 min.

[0051] Example 4

[0052] (1) Aluminum alloy frame design and SLM printing: First, an equilateral triangle structure with a thickness of 0.4 mm and a single frame side length of 3.5 mm was designed. Then, AlSi12 alloy powder, which had been kept at 90℃ for 9 hours under vacuum, was placed into the printer's powder supply chamber. The printer's laser power was set to 380W, the scanning speed to 1175 mm / s, the scanning strategy to have the laser scanning directions of adjacent layers at 79°, the scanning interval to 140 μm, and the powder layer thickness to 50 μm. (The alloy powder particle size and powder layer thickness were similar.) The printed frame is shown below. Figure 2 As shown.

[0053] (2) Preform preparation: First, Al 20 Fe 20 Co 20 Cr 20 Ni 20 High-entropy alloy powder is densely and uniformly filled into the AlSi12 aluminum alloy topological structure framework to obtain a preform; then the preform is fixed as a whole in a cylindrical graphite groove with its own holes. The graphite groove and the preform cooperate with each other. The holes in the groove are circular with a diameter of 0.45mm.

[0054] (3) Aluminum alloy melting and preheating of preform: Weigh an AlSi12 block with a mass 5.5 times that of the preform, put it into a melting furnace and heat it at 7℃ / min to the melting temperature of 250℃ and hold it for 3.5h to obtain aluminum alloy melt; put the preform together with the graphite mold into a steel mold, heat the preform to 380℃ and hold it for 3h.

[0055] (4) Preparation of layered aluminum matrix composite material: Molten aluminum alloy was poured into a steel mold using a hydraulic press, followed by pressure infiltration. After the molten aluminum alloy completely penetrated the preform under pressure, it cooled and solidified to obtain a layered aluminum matrix composite material reinforced with high-entropy alloy particles. The pressure during pressure infiltration was set to 85 MPa, the holding time was set to 8 min, and the cooling time was set to 8 min.

[0056] Example 5

[0057] (1) Aluminum alloy frame design and SLM printing: First, an equilateral triangular structure with a thickness of 0.7 mm and a single frame length of 4 mm was designed. Then, AlSi12 alloy powder, which had been kept at 80℃ for 2 hours under vacuum, was placed into the printer's powder supply hopper. The printer's laser power was set to 250 W, the scanning speed to 1200 mm / s, the scanning strategy to have the laser scanning directions of adjacent layers at 77°, the scanning interval to 105 μm, and the powder layer thickness to 55 μm. (The alloy powder particle size and powder layer thickness were similar.)

[0058] (2) Preform preparation: First, Fe 20 Co 20 Mn 20 Ni 20 Cu 20 High-entropy alloy powder is densely and uniformly filled into the AlSi12 aluminum alloy topological structure framework to obtain a preform; then the preform is fixed as a whole in a cylindrical graphite groove with its own holes. The graphite groove and the preform cooperate with each other, and the holes in the groove are circular with a diameter of 0.5mm.

[0059] (3) Aluminum alloy melting and preheating of preform: Weigh an AlSi12 block with a mass 6 times that of the preform, put it into a melting furnace and heat it at a rate of 6℃ / min to a melting temperature of 270℃ and hold it for 1.5h to obtain aluminum alloy melt; put the preform together with the graphite mold into a steel mold, heat the preform to 400℃ and hold it for 3h.

[0060] (4) Preparation of layered aluminum matrix composite material: Molten aluminum alloy was poured into a steel mold using a hydraulic press, followed by pressure infiltration. After the molten aluminum alloy completely penetrated the preform under pressure, it cooled and solidified to obtain a layered aluminum matrix composite material reinforced with high-entropy alloy particles. The pressure during pressure infiltration was set to 90 MPa, the holding time to 11 min, and the cooling time to 9 min.

[0061] Example 6

[0062] (1) Aluminum alloy frame design and SLM printing: First, an equilateral triangle structure with a thickness of 1 mm and a single frame length of 5 mm was designed. Then, AlSi12 alloy powder, which had been kept at 75℃ for 3 hours under vacuum, was placed into the printer's powder supply hopper. The printer's laser power was set to 200W, the scanning speed to 1250 mm / s, the scanning strategy to have the laser scanning directions of adjacent layers at 69°, the scanning interval to 110 μm, and the powder layer thickness to 60 μm. (The alloy powder particle size and powder layer thickness were similar.)

[0063] (2) Preform preparation: First, Fe 20 Co 20 Cr 20 Ni 20 Mo 20 High-entropy alloy powder is densely and uniformly filled into the AlSi12 aluminum alloy topological structure framework to obtain a preform; then the preform is fixed as a whole in a cylindrical graphite groove with its own holes. The graphite groove and the preform cooperate with each other, and the holes in the groove are circular with a diameter of 0.6mm.

[0064] (3) Aluminum alloy melting and preheating of preform: Weigh an AlSi12 block with a mass 7 times that of the preform, put it into a melting furnace and heat it at 10℃ / min to the melting temperature of 280℃ and hold it for 1h to obtain aluminum alloy melt; put the preform together with the graphite mold into a steel mold, heat the preform to 520℃ and hold it for 3h.

[0065] (4) Preparation of layered aluminum matrix composite material: Molten aluminum alloy was poured into a steel mold using a hydraulic press, followed by pressure infiltration. After the molten aluminum alloy completely penetrated the preform under pressure, it cooled and solidified to obtain a layered aluminum matrix composite material reinforced with high-entropy alloy particles. The pressure during pressure infiltration was set to 95 MPa, the holding time to 6 min, and the cooling time to 6 min.

[0066] Example 7

[0067] (1) Aluminum alloy frame design and SLM printing: First, a regular hexagonal structure with a thickness of 0.4 mm and a single frame size of 2 mm was designed. Then, AlSi7Mg alloy powder, which had been kept at 85℃ for 4 hours under vacuum, was placed into the printer's powder supply hopper. The printer's laser power was set to 370W, the scanning speed to 1300 mm / s, the scanning strategy to have the laser scanning directions of adjacent layers at 75°, the scanning interval to 115 μm, and the powder layer thickness to 35 μm. (The alloy powder particle size and powder layer thickness were similar.) The printed frame is shown below. Figure 2 As shown.

[0068] (2) Preform preparation: First, Al 20 Ti 20 Cr20 Ni 20 Cu 20 High-entropy alloy powder is densely and uniformly filled into the AlSi7Mg aluminum alloy topological structure framework to obtain a preform; then the preform is fixed as a whole in a cylindrical graphite groove with its own holes. The graphite groove and the preform cooperate with each other. The holes in the groove are circular with a diameter of 0.65mm.

[0069] (3) Aluminum alloy melting and preheating of preform: Weigh AlSi7Mg block with a mass of 4.5 times that of preform, put it into the melting furnace and heat it at 7℃ / min to the melting temperature of 290℃ and hold it for 2h to obtain aluminum alloy melt; put the preform together with the graphite mold into the steel mold, heat the preform to 560℃ and hold it for 4h.

[0070] (4) Preparation of layered aluminum matrix composite material: Molten aluminum alloy was poured into a steel mold using a hydraulic press, followed by pressure infiltration. After the molten aluminum alloy completely penetrated the preform under pressure, it cooled and solidified to obtain a layered aluminum matrix composite material reinforced with high-entropy alloy particles. The pressure during pressure infiltration was set to 100 MPa, the holding time to 5 min, and the cooling time to 7 min.

[0071] Example 8

[0072] (1) Aluminum alloy frame design and SLM printing: First, a regular hexagonal structure with a thickness of 0.6 mm and a single frame size of 4 mm was designed. Then, AlSi7Mg alloy powder, which had been kept at 95℃ for 5 hours under vacuum, was placed into the printer's powder supply hopper. The printer's laser power was set to 360W, the scanning speed to 1350 mm / s, the scanning strategy to have the laser scanning directions of adjacent layers at 76°, the scanning interval to 125 μm, and the powder layer thickness to 30 μm. (The alloy powder particle size and powder layer thickness were similar.)

[0073] (2) Preform preparation: First, Fe 20 Co 20 Cr20Ni 20 Cu 20 High-entropy alloy powder is densely and uniformly filled into the AlSi7Mg aluminum alloy topological structure framework to obtain a preform; then the preform is fixed as a whole in a cylindrical graphite groove with its own holes. The graphite groove and the preform cooperate with each other. The holes in the groove are circular with a diameter of 0.7mm.

[0074] (3) Aluminum alloy melting and preheating of preform: Weigh AlSi7Mg block with a mass of 5 times that of preform, put it into the melting furnace and heat it. The temperature is raised to 140℃ at 8℃ / min and then held for 4h to obtain aluminum alloy melt. Put the preform together with the graphite mold into the steel mold, heat the preform to 580℃ and hold for 4h.

[0075] (4) Preparation of layered aluminum matrix composite material: Molten aluminum alloy was poured into a steel mold using a hydraulic press, followed by pressure infiltration. After the molten aluminum alloy completely penetrated the preform under pressure, it cooled and solidified to obtain a layered aluminum matrix composite material reinforced with high-entropy alloy particles. The pressure during pressure infiltration was set to 105 MPa, the holding time to 9 min, and the cooling time to 8 min.

[0076] Example 9

[0077] (1) Aluminum alloy frame design and SLM printing: First, a regular hexagonal structure with a thickness of 0.8 mm and a single frame size of 6 mm was designed. Then, AlSi7Mg alloy powder, which had been kept at 65℃ for 6 hours under vacuum, was placed into the printer's powder supply hopper. The printer's laser power was set to 365W, the scanning speed to 1400 mm / s, the scanning strategy to have the laser scanning directions of adjacent layers at 77°, the scanning interval to 135 μm, and the powder layer thickness to 35 μm. (The alloy powder particle size and powder layer thickness were similar.)

[0078] (2) Preform preparation: First, Al 20 Ti 20 Cr 20 Co 20 Cu 20 High-entropy alloy powder is densely and uniformly filled into the AlSi7Mg aluminum alloy topological structure framework to obtain a preform; then the preform is fixed as a whole in a cylindrical graphite groove with its own holes. The graphite groove and the preform cooperate with each other. The holes in the groove are circular with a diameter of 0.8mm.

[0079] (3) Aluminum alloy melting and preheating of preform: Weigh AlSi7Mg block with a mass of 3.5 times that of preform, put it into the melting furnace and heat it at 9℃ / min to the melting temperature of 120℃ and hold it for 1h to obtain aluminum alloy melt; put the preform together with the graphite mold into the steel mold, heat the preform to 600℃ and hold it for 3.5h.

[0080] (4) Preparation of layered aluminum matrix composite material: Molten aluminum alloy was poured into a steel mold using a hydraulic press, followed by pressure infiltration. After the molten aluminum alloy completely penetrated the preform under pressure, it cooled and solidified to obtain a layered aluminum matrix composite material reinforced with high-entropy alloy particles. The pressure during pressure infiltration was set to 110 MPa, the holding time to 10 min, and the cooling time to 9 min.

[0081] The above embodiments are merely preferred embodiments of the present invention and are only used to explain the present invention, not to limit the present invention. Any changes, substitutions, modifications, etc., made by those skilled in the art without departing from the spirit and essence of the present invention should be within the protection scope of the present invention.

Claims

1. A preparation process for a layered aluminum matrix composite material reinforced with high-entropy alloy particles, characterized in that, Includes the following steps: (1) Aluminum alloy frame design and SLM printing: Design layered topological structure frames with different shapes, sizes and thicknesses; then load vacuum-dried aluminum alloy powder into the printer powder supply hopper, spread the powder evenly in the printer powder spreading hopper, adjust the printing parameters according to the two-dimensional slices of the three-dimensional model input by the printer, and print after printing. After printing is completed, an aluminum alloy layered topological structure frame is obtained; the aluminum alloy powder is an Al-Si alloy suitable for laser selective melting forming technology (SLM). (2) Preform preparation: The high-entropy alloy powder is tightly and uniformly filled into the aluminum alloy layered topological structure framework obtained in step (1) to obtain the preform. Then, the preform is fixed as a whole in a cylindrical graphite groove with suitable size and self-hole. The graphite groove and the preform cooperate with each other. The selected high-entropy alloy powder includes FeCoCrNi system, FeCoMnNi system, AlFeCoCrNi system or AlTi system. (3) Aluminum alloy melting and preform preheating: Weigh aluminum alloy, put it into a melting furnace for heating, melting and holding, and refining to obtain aluminum alloy melt; put the preform obtained in step (2) together with the graphite mold into a steel mold and heat and hold it. (4) Preparation of layered aluminum matrix composite material: The aluminum alloy melt obtained in step (3) is cast into a steel mold using a hydraulic press, and then pressure infiltration is performed; after the aluminum alloy melt is completely penetrated into the preform under pressure, it is cooled and solidified to obtain a layered aluminum matrix composite material reinforced with high entropy alloy particles.

2. The preparation process of the high-entropy alloy particle-reinforced layered aluminum matrix composite material according to claim 1, characterized in that, In step (1), the designed layered topological structure framework includes various polygons; the polygons include triangles, quadrilaterals or hexagons, with a side length range of 1mm-10mm and a thickness range of 0.1mm-1mm.

3. The preparation process of the high-entropy alloy particle-reinforced layered aluminum matrix composite material according to claim 1, characterized in that, In step (1), the aluminum alloy powder includes AlSi10Mg, AlSi12 or AlSi7Mg; the particle size of the aluminum alloy powder ranges from 10 to 100 μm, and the purity ranges from 99% to 99.99%.

4. The preparation process of the high-entropy alloy particle-reinforced layered aluminum matrix composite material according to claim 1, characterized in that, In step (1), aluminum alloy powder is placed in a vacuum drying oven and heated to 60-100℃, and then kept at that temperature for 2-10 hours.

5. The preparation process of the high-entropy alloy particle-reinforced layered aluminum matrix composite material according to claim 1, characterized in that, In step (1), the printing parameters of the layered topological structure frame are: laser power of 200-400W, scanning speed of 1100-1400mm / s, scanning strategy of laser scanning direction of adjacent two layers at 60°-70°, scanning distance of 100-150μm, and powder layer thickness of 10-100μm.

6. The preparation process of the high-entropy alloy particle-reinforced layered aluminum matrix composite material according to claim 1, characterized in that, In step (2), the particle size of the high-entropy alloy powder ranges from 10 to 100 μm, and the purity ranges from 99% to 99.99%. The holes in the cylindrical graphite grooves are circular, with a diameter of 0.1-2 mm.

7. The preparation process of the high-entropy alloy particle-reinforced layered aluminum matrix composite material according to claim 1, characterized in that, In step (3), the composition of the aluminum alloy is consistent with that of the aluminum alloy powder in step (1); the mass of the aluminum alloy is 3-10 times the mass of the preform.

8. The preparation process of the high-entropy alloy particle-reinforced layered aluminum matrix composite material according to claim 1, characterized in that, In step (3), the aluminum alloy block is heated to 100-300°C above its melting point at a heating rate of 5-10°C / min, and held for 0.5-4 hours.

9. The preparation process of the high-entropy alloy particle-reinforced layered aluminum matrix composite material according to claim 1, characterized in that, In step (3), the preform is heated to 200-600℃ and kept warm for 2-4 hours.

10. The preparation process of a high-entropy alloy particle-reinforced layered aluminum matrix composite material according to claim 1, characterized in that, In step (4), the pressure during the pressure impregnation process is set to 40-120 MPa, the pressure holding time is set to 2-15 min, and the cooling time is set to 2-15 min.

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