A three-dimensional porous high-entropy alloy reinforced aluminum matrix composite material and a preparation method thereof

Abstract

The present invention discloses a three-dimensional porous high-entropy alloy reinforced aluminum matrix composite and its preparation method, which is composed of 60-70% aluminum alloy matrix and 30-40% three-dimensional porous high-entropy alloy; the components of the aluminum alloy matrix are: Zn, Mg, Cu, Cr, Fe, Si and Al; the components of the three-dimensional porous high-entropy alloy are Ti 20‑25 Mg 20‑25 Fe 15‑20 Cr 15‑20 Ni 10‑ 15 La 5‑10 , and 1-5% of Y2O3 is added, and it has a three-dimensional connected open pore structure, the porosity is 60-70%, and there is a 1-2 μm nitrided layer on the surface. The present invention uses sodium chloride particles as the pore-forming agent, uses a method combining mechanical alloying and plasma discharge sintering to prepare the high-entropy alloy reinforcement, and performs nitriding treatment, and then uses pressure infiltration method for casting. The material prepared by the present invention has high strength and high hardness, excellent comprehensive mechanical properties, and broad application prospects.

Description

Technical Field

[0001] The present invention relates to the technical field of alloys, and particularly to a three-dimensional porous high-entropy alloy reinforced aluminum matrix composite material. Background Art

[0002] Aluminum matrix composites are one of the most studied and widely used materials in metal matrix composites. With the advantages of low density, high specific strength and specific stiffness, wear and fatigue resistance, low thermal expansion coefficient, good electrical and thermal conductivity, and abundant aluminum resources, it is easy to process into plastic materials, which can significantly reduce the industrial manufacturing cost. Therefore, it has a wide range of applications in many industries such as aerospace, military, electronics, automotive, and sports. The reinforcements of aluminum matrix composites include particles, whiskers (discontinuous short fibers), and continuous long fibers and other reinforcing substances. Different types of reinforcements have different characteristics. Fibers themselves have high strength and modulus, so long fiber reinforcement has a better effect, but it has anisotropy, and the axial and transverse reinforcement effects are very different; although discontinuous short fibers and particles show isotropy, the agglomeration problem inside the material is difficult to solve, which has a greater impact on the performance of the material. The commonly used reinforcement components of aluminum matrix composites mainly include non-metals or ceramics such as boron, carbon (graphite), alumina, silicon carbide, titanium boride, etc. These reinforcements can effectively improve the strength and hardness of the material, but the price is usually the reduction of plasticity. In addition, the poor wettability and interfacial reaction problems between the reinforcement and the aluminum alloy matrix will also affect the performance of the aluminum matrix composite material.

[0003] With the increasing requirements of modern technology for material properties, it is particularly important to develop new aluminum matrix composites, especially to find more suitable composite reinforcements and corresponding more perfect preparation processes to further improve the performance of aluminum matrix composites. Summary of the Invention

[0004] Technical Problem to be Solved: The technical problem to be solved by the present invention is to provide a three-dimensional porous high-entropy alloy reinforced aluminum matrix composite material with high strength and high hardness and excellent comprehensive mechanical properties.

[0005] Technical Solution: A three-dimensional porous high-entropy alloy reinforced aluminum matrix composite material is composed of 60 - 70% aluminum alloy matrix and 30 - 40% three-dimensional porous high-entropy alloy. The three-dimensional porous high-entropy alloy is a three-dimensionally connected open-cell structure with a porosity of 60 - 70% and a 1 - 2 μm nitride layer on the surface.

[0006] Preferably, the preparation method of the three-dimensional porous high-entropy alloy reinforced aluminum matrix composite material includes the following steps:

[0007] S1. Prepare the raw material powders required for the high-entropy alloy according to the proportion, and carry out mechanical alloying ball milling to mix them evenly. Add a pore-forming agent and a binder, and ball mill again to mix evenly and form a paste to obtain a uniform raw material;

[0008] S2. Put the raw material prepared in S1 into a mold for cold pressing and drying, then put it into a vacuum sintering furnace for pre-sintering, remove the pore-forming agent by water bath and dry it, and then carry out secondary sintering by plasma discharge sintering method to obtain a three-dimensional porous high-entropy alloy;

[0009] S3. Clean the three-dimensional porous high-entropy alloy prepared in S2, put it into a plasma nitriding device, introduce a mixed atmosphere of hydrogen and nitrogen and heat it for nitriding, and then cool it to room temperature in the furnace to obtain a three-dimensional porous high-entropy alloy with a nitrided layer on the surface;

[0010] S4. Place the three-dimensional porous high-entropy alloy prepared in S3 at the bottom and aluminum alloy at the top in a crucible, evacuate the vacuum, preheat the three-dimensional porous high-entropy alloy, then heat to melt the aluminum alloy and fill it with argon for pressurization, keep the temperature and pressure until infiltration is completed and then solidify to obtain a three-dimensional porous high-entropy alloy reinforced aluminum matrix composite.

[0011] Preferably, the rotation speed of the mechanical alloying ball milling in step S1 is 300 - 350 r / min, and the ball milling time is 20 - 24 h.

[0012] Preferably, the pore-forming agent in step S1 is NaCl, the particle size is 200 - 300 μm, and the addition amount of NaCl is 100 - 150% of the volume of the metal powder; the binder is absolute ethanol, and the addition amount of absolute ethanol is 7 - 10% of the mass of the metal powder.

[0013] Preferably, the pre-sintering temperature in step S2 is 750 - 800 °C, and the holding time is 4 - 6 h; the secondary sintering temperature is 1100 - 1300 °C, and the holding time is 3 - 5 h.

[0014] Preferably, the heating temperature in step S3 is 480 - 520 °C, the nitriding time is 1 - 2 h, and the ratio of nitrogen to hydrogen in the mixed atmosphere is 1:1 - 2.

[0015] Preferably, the preheating temperature of the three-dimensional porous high-entropy alloy in step S4 is 400 - 420 °C, and the heating temperature of the molten aluminum alloy is 720 - 780 °C.

[0016] Preferably, the composition of the aluminum alloy matrix consists of the following weight percentages: Zn: 5.5 - 6.0 wt%, Mg: 2.0 - 2.5 wt%, Cu: 1.3 - 1.7 wt%, Cr: 0.15 - 0.33 wt%, Fe: ≤0.15 wt%, Si: ≤0.1 wt%, and the balance is Al.

[0017] Preferably, the composition of the three-dimensional porous high-entropy alloy is Ti 20-25 Mg 20-25 Fe 15-20 Cr 15-20 Ni 10-15 La 5-10 , and 1 - 5% of Y2O3 is added.

[0018] Beneficial effects: In the aluminum matrix composite material of the present invention, the three-dimensional porous high-entropy alloy is used as the reinforcement. It not only has high strength and high hardness, but also has good interfacial bonding with the matrix. At the same time, the three-dimensional structure makes the material isotropic, improving the comprehensive performance of the material.

[0019] Ceramics are commonly used reinforcements for aluminum matrix composites, which can significantly improve the strength and hardness of the material, but the wettability between the two is poor and the bonding is not good. The configurational entropy of high-entropy alloys is relatively high, and they tend to form simple solid solution structures such as FCC and BCC rather than intermetallic compounds. Therefore, they have excellent comprehensive properties, such as high strength, high and low temperature toughness, thermal stability, wear resistance, corrosion resistance, etc. They are not inferior to ceramics in terms of comprehensive performance, and have the advantage of good metal-metal interfacial bonding with the aluminum matrix, and are ideal reinforcements for metal matrix composites. Preparing the high-entropy alloy into a three-dimensionally connected open-cell structure as the reinforcement of the aluminum matrix composite material to form a three-dimensional interpenetrating structure with the matrix can solve the problems of unstable material performance caused by uneven dispersion of the reinforcement phase and performance differences in different orientations of the material caused by the anisotropy of the reinforcement phase. Moreover, the specific surface area of the porous material is large and the contact surface with the matrix is many, which is beneficial to further improving the bonding force between the two phases and improving the material stability. Adding a small amount of Y2O3 during the sintering process of the high-entropy alloy can effectively reduce the porosity of the sintered parts, improve the sintering quality, and make the impurities in the material be dispersed, reducing the influence of impurities on the performance of the high-entropy alloy, and at the same time playing a role in refining the grains, further improving the strength, hardness and corrosion resistance of the material. In addition, performing plasma nitriding treatment on the three-dimensional porous high-entropy alloy to form a nitride film on its surface can increase the surface roughness of the alloy, improve the bonding force between the matrix and the high-entropy alloy, and reduce the element diffusion between the two interfaces, so that the reinforcement phase can still maintain a stable composition during the casting process and under high-temperature working environments. In addition, the nitride film can also improve the hardness and corrosion resistance of the high-entropy alloy, optimizing the comprehensive performance of the material.

[0020] Compared with the prior art, the present invention has the following advantages and positive effects:

[0021] The present invention adds a high-entropy alloy with high strength and high hardness as a composite material reinforcement, which can effectively improve the mechanical properties of the material. At the same time, a metal-metal interface is formed between the reinforcement and the matrix, with strong bonding force and good material stability.

[0022] The present invention prepares the reinforcement into a three-dimensional porous network morphology, solves the anisotropy problem of fiber reinforcements and the uneven distribution problem of particle reinforcements, and improves the comprehensive performance of the material.

[0023] The present invention uses the pressure infiltration method to prepare the composite material, which can reduce the defects of the material and the interfacial reaction between the two phases, and improve the performance and quality of the material. Specific Embodiments

[0024] To further understand the present invention, the preferred embodiments of the present invention will be described below in conjunction with examples.

[0025] The specific preferred examples are as follows:

[0026] Example 1

[0027] A three-dimensional porous high-entropy alloy reinforced aluminum matrix composite material is composed of 70% aluminum alloy matrix and 30% three-dimensional porous high-entropy alloy. The three-dimensional porous high-entropy alloy is a three-dimensionally connected open-cell structure with a porosity of 70% and a 1-2 μm nitride layer on the surface;

[0028] The preparation method of the three-dimensional porous high-entropy alloy reinforced aluminum matrix composite material includes the following steps:

[0029] S1. Prepare the raw material powders required for the high-entropy alloy according to the ratio, and carry out mechanical alloying ball milling to mix evenly. The ball milling speed is 320 r / min, the ball milling time is 24 h. Add NaCl particles with a particle size of 200-300 μm as a pore-forming agent and absolute ethanol as a binder, and ball mill again to mix evenly and form a paste. The addition amount of the pore-forming agent is 150% of the volume of the metal powder, and the addition amount of the binder is 8% of the mass of the metal powder to obtain a uniform raw material;

[0030] S2. Put the raw material prepared in S1 into a mold, cold press and dry it, then put it into a vacuum sintering furnace for pre-sintering. The pre-sintering temperature is 780 °C, the holding time is 5 h. Remove the pore-forming agent by water bath and dry it, and then carry out secondary sintering by plasma discharge sintering method. The sintering temperature is 1100 °C, and the holding time is 4 h to obtain a three-dimensional porous high-entropy alloy;

[0031] S3. Clean the three-dimensional porous high-entropy alloy prepared in S2, place it in a plasma nitriding device, introduce a mixed atmosphere of nitrogen and hydrogen with a ratio of 1:2, and heat it to 500 °C for nitriding for 1.5 h, then cool it in the furnace to room temperature to obtain a three-dimensional porous high-entropy alloy with a nitrided layer on the surface;

[0032] S4. Place the three-dimensional porous high-entropy alloy prepared in S3 below and aluminum alloy above in a crucible, evacuate the air, heat it to 400 °C to preheat the three-dimensional porous high-entropy alloy, and then heat it to 720 °C to melt the aluminum alloy and fill it with argon under pressure. Keep it at a constant temperature and pressure until infiltration is completed and then solidify to obtain a three-dimensional porous high-entropy alloy reinforced aluminum matrix composite;

[0033] The composition of the aluminum alloy matrix consists of the following weight percentages: Zn: 5.5 wt%, Mg: 2.44 wt%, Cu: 1.52 wt%, Cr: 0.17 wt%, Fe: 0.12 wt%, Si: 0.1 wt%, and the balance is Al;

[0034] The composition of the three-dimensional porous high-entropy alloy is Ti 25 Mg 20 Fe 20 Cr 15 Ni 15 La5, and 1% of Y2O3 is added.

[0035] Example 2:

[0036] A three-dimensional porous high-entropy alloy reinforced aluminum matrix composite consists of 65% aluminum alloy matrix and 35% three-dimensional porous high-entropy alloy. The three-dimensional porous high-entropy alloy has a three-dimensionally connected open-cell structure, a porosity of 65%, and a nitrided layer with a thickness of 1 - 2 μm on the surface;

[0037] The preparation method of the three-dimensional porous high-entropy alloy reinforced aluminum matrix composite includes the following steps:

[0038] S1. Prepare the raw material powders required for the high-entropy alloy according to the ratio, and carry out mechanical alloying ball milling to mix them evenly. The ball milling speed is 320 r / min, and the ball milling time is 24 h. Add pore-forming agent NaCl particles with a particle size of 200 - 300 μm and binder absolute ethanol, and ball mill and mix them evenly again to form a paste. The addition amount of the pore-forming agent is 125% of the volume of the metal powder, and the addition amount of the binder is 8% of the mass of the metal powder to obtain a uniform raw material;

[0039] S2. Put the raw materials prepared in S1 into a mold, cold-press and dry them, then put them into a vacuum sintering furnace for pre-sintering. The pre-sintering temperature is 780 °C, and the heat preservation time is 5 h. Remove the pore-forming agent by water bath and dry it. Then, perform secondary sintering by plasma discharge sintering method. The sintering temperature is 1100 °C, and the heat preservation time is 4 h to obtain a three-dimensional porous high-entropy alloy;

[0040] S3. Clean the three-dimensional porous high-entropy alloy prepared in S2, put it into a plasma nitriding device, introduce a mixed atmosphere with a ratio of nitrogen to hydrogen of 1:2, and heat it to 500 °C for nitriding for 1.5 h, then cool it to room temperature in the furnace to obtain a three-dimensional porous high-entropy alloy with a nitrided layer on the surface;

[0041] S4. Place the three-dimensional porous high-entropy alloy prepared in S3 below and aluminum alloy above in a crucible, evacuate the air, heat it to 400 °C to preheat the three-dimensional porous high-entropy alloy, and then heat it to 720 °C to melt the aluminum alloy and fill it with argon for pressurization. Keep the temperature and pressure until infiltration is completed and then solidify to obtain a three-dimensional porous high-entropy alloy reinforced aluminum matrix composite;

[0042] The composition of the aluminum alloy matrix consists of the following weight percentages: Zn: 5.94 wt%, Mg: 2.0 wt%, Cu: 1.33 wt%, Cr: 0.31 wt%, Fe: 0.15 wt%, and the balance is Al;

[0043] The composition of the three-dimensional porous high-entropy alloy is Ti 25 Mg 20 Fe 20 Cr 15 Ni 15 La5, and 1% of Y2O3 is added.

[0044] Example 3:

[0045] A three-dimensional porous high-entropy alloy reinforced aluminum matrix composite is composed of 60% aluminum alloy matrix and 40% three-dimensional porous high-entropy alloy. The three-dimensional porous high-entropy alloy is a three-dimensionally connected open-cell structure with a porosity of 60%, and has a nitrided layer with a thickness of 1 - 2 μm on the surface;

[0046] The preparation method of the three-dimensional porous high-entropy alloy reinforced aluminum matrix composite includes the following steps:

[0047] S1. Prepare the raw material powders required for the high-entropy alloy according to the proportion, and carry out mechanical alloying ball milling to mix evenly. The ball milling speed is 320 r / min, and the ball milling time is 24 h. Add pore-forming agent NaCl particles with a particle size of 200 - 300 μm and binder absolute ethanol, and ball mill again to mix evenly and form a paste. The addition amount of the pore-forming agent is 100% of the volume of the metal powder, and the addition amount of the binder is 8% of the mass of the metal powder to obtain a uniform raw material;

[0048] S2. Put the raw material prepared in S1 into a mold for cold pressing and drying, then put it into a vacuum sintering furnace for pre-sintering. The pre-sintering temperature is 780 °C, and the holding time is 5 h. Remove the pore-forming agent by water bath and dry it, and then carry out secondary sintering by plasma discharge sintering method. The sintering temperature is 1100 °C, and the holding time is 4 h to obtain a three-dimensional porous high-entropy alloy;

[0049] S3. Clean the three-dimensional porous high-entropy alloy prepared in S2, put it into a plasma nitriding device, introduce a mixed atmosphere with a ratio of nitrogen to hydrogen of 1:2, and heat it to 500 °C for nitriding for 1.5 h, and then cool it to room temperature in the furnace to obtain a three-dimensional porous high-entropy alloy with a nitrided layer on the surface;

[0050] S4. Place the three-dimensional porous high-entropy alloy prepared in S3 below and aluminum alloy above in a crucible, evacuate the vacuum, heat it to 400 °C to preheat the three-dimensional porous high-entropy alloy, and then heat it to 720 °C to melt the aluminum alloy and fill it with argon for pressurization. Keep the temperature and pressure until infiltration is completed and then solidify to obtain a three-dimensional porous high-entropy alloy reinforced aluminum matrix composite;

[0051] The composition of the aluminum alloy matrix consists of the following weight percentages: Zn: 5.76 wt%, Mg: 2.23 wt%, Cu: 1.7 wt%, Cr: 0.20 wt%, Fe: 0.06 wt%, Si: 0.05 wt%, and the balance is Al;

[0052] The composition of the three-dimensional porous high-entropy alloy is Ti 25 Mg 20 Fe 20 Cr 15 Ni 15 La5, and 1% of Y2O3 is added.

[0053] Example 4:

[0054] A three-dimensional porous high-entropy alloy reinforced aluminum matrix composite is composed of 65% aluminum alloy matrix and 35% three-dimensional porous high-entropy alloy. Among them, the three-dimensional porous high-entropy alloy is a three-dimensionally connected open-pore structure, the porosity is 65%, and there is a 1 - 2 μm nitrided layer on the surface;

[0055] The preparation method of the three-dimensional porous high-entropy alloy reinforced aluminum matrix composite material comprises the following steps:

[0056] S1. Prepare the raw material powders required for the high-entropy alloy according to the proportion, and carry out mechanical alloying ball milling to mix them evenly. The ball milling speed is 320 r / min, and the ball milling time is 24 h. Add pore-forming agent NaCl particles with a particle size of 200 - 300 μm and binder absolute ethanol, and ball mill and mix them evenly again to form a paste. The addition amount of the pore-forming agent is 125% of the volume of the metal powder, and the addition amount of the binder is 8% of the mass of the metal powder to obtain a uniform raw material;

[0057] S2. Put the raw material prepared in S1 into a mold, cold press and form it, and then dry it. Put it into a vacuum sintering furnace for pre-sintering. The pre-sintering temperature is 780 °C, and the heat preservation time is 5 h. Remove the pore-forming agent by water bath and dry it. Then, carry out secondary sintering by plasma discharge sintering method. The sintering temperature is 1150 °C, and the heat preservation time is 4 h to obtain a three-dimensional porous high-entropy alloy;

[0058] S3. Clean the three-dimensional porous high-entropy alloy prepared in S2, put it into a plasma nitriding equipment, introduce a mixed atmosphere with a ratio of nitrogen to hydrogen of 1:2, and heat it to 500 °C for nitriding for 1.5 h, and then cool it to room temperature in the furnace to obtain a three-dimensional porous high-entropy alloy with a nitrided layer on the surface;

[0059] S4. Place the three-dimensional porous high-entropy alloy prepared in S3 at the bottom and aluminum alloy at the top in a crucible, evacuate it, heat it to 400 °C to preheat the three-dimensional porous high-entropy alloy, and then heat it to 720 °C to melt the aluminum alloy and fill it with argon for pressurization. Keep the temperature and pressure until infiltration is completed and then solidify it to obtain a three-dimensional porous high-entropy alloy reinforced aluminum matrix composite material;

[0060] The composition of the aluminum alloy matrix consists of the following weight percentages: Zn: 5.88 wt%, Mg: 2.37 wt%, Cu: 1.42 wt%, Cr: 0.33 wt%, Si: 0.08 wt%, and the balance is Al;

[0061] The composition of the three-dimensional porous high-entropy alloy is Ti 25 Mg 20 Fe 20 Cr 15 Ni 15 La5, and 1% of Y2O3 is added.

[0062] Example 5:

[0063] A three-dimensional porous high-entropy alloy reinforced aluminum matrix composite consists of 65% aluminum alloy matrix and 35% three-dimensional porous high-entropy alloy. The three-dimensional porous high-entropy alloy has a three-dimensionally connected open-cell structure with a porosity of 65% and a 1-2 μm thick nitride layer on its surface.

[0064] The preparation method of the three-dimensional porous high-entropy alloy reinforced aluminum matrix composite includes the following steps:

[0065] S1. Prepare the raw material powders required for the high-entropy alloy according to the proportion, and carry out mechanical alloying ball milling to mix them evenly. The ball milling speed is 320 r / min, and the ball milling time is 24 h. Add pore-forming agent NaCl particles with a particle size of 200-300 μm and binder anhydrous ethanol, and ball mill and mix them evenly again to form a paste. The addition amount of the pore-forming agent is 125% of the volume of the metal powder, and the addition amount of the binder is 8% of the mass of the metal powder to obtain a uniform raw material.

[0066] S2. Put the raw material prepared in S1 into a mold, cold press and dry it, then put it into a vacuum sintering furnace for pre-sintering. The pre-sintering temperature is 780 °C, and the holding time is 5 h. Remove the pore-forming agent by water bath and dry it, and then carry out secondary sintering by plasma discharge sintering method. The sintering temperature is 1200 °C, and the holding time is 4 h to obtain a three-dimensional porous high-entropy alloy.

[0067] S3. Clean the three-dimensional porous high-entropy alloy prepared in S2, put it into a plasma nitriding equipment, introduce a mixed atmosphere with a ratio of nitrogen to hydrogen of 1:2, and heat it to 500 °C for nitriding for 1.5 h, and then cool it to room temperature in the furnace to obtain a three-dimensional porous high-entropy alloy with a nitride layer on its surface.

[0068] S4. Place the three-dimensional porous high-entropy alloy prepared in S3 at the bottom and the aluminum alloy on top in a crucible, evacuate the air, heat it to 400 °C to preheat the three-dimensional porous high-entropy alloy, and then heat it to 720 °C to melt the aluminum alloy and fill it with argon for pressurization. Keep the temperature and pressure until infiltration is completed and then solidify to obtain a three-dimensional porous high-entropy alloy reinforced aluminum matrix composite.

[0069] The composition of the aluminum alloy matrix consists of the following weight percentages: Zn: 5.57 wt%, Mg: 2.15 wt%, Cu: 1.52 wt%, Cr: 0.18 wt%, Fe: 0.11 wt%, Si: 0.04 wt%, and the balance is Al.

[0070] The composition of the three-dimensional porous high-entropy alloy is Ti 25 Mg 20 Fe 20 Cr 15 Ni 15 La5, and 1% of Y2O3 is added.

[0071] Example 6:

[0072] A three-dimensional porous high-entropy alloy reinforced aluminum matrix composite is composed of 65% aluminum alloy matrix and 35% three-dimensional porous high-entropy alloy. The three-dimensional porous high-entropy alloy has a three-dimensionally connected open-cell structure, a porosity of 65%, and a 1-2 μm thick nitride layer on its surface;

[0073] The preparation method of the three-dimensional porous high-entropy alloy reinforced aluminum matrix composite includes the following steps:

[0074] S1. Prepare the raw material powders required for the high-entropy alloy according to the ratio, and carry out mechanical alloying ball milling to mix evenly. The ball milling speed is 320 r / min, the ball milling time is 24 h. Add pore-forming agent NaCl particles with a particle size of 200-300 μm and binder absolute ethanol, and ball mill again to mix evenly and form a paste. The addition amount of the pore-forming agent is 125% of the volume of the metal powder, and the addition amount of the binder is 8% of the mass of the metal powder to obtain a uniform raw material;

[0075] S2. Put the raw material prepared in S1 into a mold, cold press and dry it, then put it into a vacuum sintering furnace for pre-sintering. The pre-sintering temperature is 780 °C, the holding time is 5 h. Remove the pore-forming agent by water bath and dry it, and then carry out secondary sintering by plasma discharge sintering. The sintering temperature is 1250 °C, the holding time is 4 h to obtain a three-dimensional porous high-entropy alloy;

[0076] S3. Clean the three-dimensional porous high-entropy alloy prepared in S2, put it into a plasma nitriding equipment, introduce a mixed atmosphere with a ratio of nitrogen to hydrogen of 1:2, and heat it to 500 °C for nitriding for 1.5 h, and then cool it to room temperature in the furnace to obtain a three-dimensional porous high-entropy alloy with a nitride layer on its surface;

[0077] S4. Place the three-dimensional porous high-entropy alloy prepared in S3 at the bottom and the aluminum alloy on top in a crucible, evacuate, heat to 400 °C to preheat the three-dimensional porous high-entropy alloy, and then heat to 720 °C to melt the aluminum alloy and fill it with argon for pressurization. Hold the pressure until infiltration is completed and then solidify to obtain a three-dimensional porous high-entropy alloy reinforced aluminum matrix composite;

[0078] The composition of the aluminum alloy matrix consists of the following weight percentages: Zn: 5.94 wt%, Mg: 2.13 wt%, Cu: 1.32 wt%, Cr: 0.20 wt%, Fe: 0.15 wt%, Si: 0.05 wt%, and the balance is Al;

[0079] The composition of the three-dimensional porous high-entropy alloy is Ti 25 Mg 20 Fe 20 Cr 15Ni 15 La5, with 1% of Y2O3 added.

[0080] Example 7:

[0081] A three-dimensional porous high-entropy alloy reinforced aluminum matrix composite, which consists of 65% aluminum alloy matrix and 35% three-dimensional porous high-entropy alloy. The three-dimensional porous high-entropy alloy is a three-dimensionally connected open-cell structure with a porosity of 65%, and has a nitrided layer with a thickness of 1 - 2 μm on its surface;

[0082] The preparation method of the three-dimensional porous high-entropy alloy reinforced aluminum matrix composite includes the following steps:

[0083] S1. Prepare the raw material powders required for the high-entropy alloy according to the proportion, and carry out mechanical alloying ball milling to mix them evenly. The ball milling speed is 320 r / min, and the ball milling time is 24 h. Add pore-forming agent NaCl particles with a particle size of 200 - 300 μm and binder absolute ethanol, and ball mill and mix them evenly again to form a paste. The addition amount of the pore-forming agent is 125% of the volume of the metal powder, and the addition amount of the binder is 8% of the mass of the metal powder to obtain a uniform raw material;

[0084] S2. Put the raw material prepared in S1 into a mold, cold press and form it, then dry it. Put it into a vacuum sintering furnace for pre-sintering. The pre-sintering temperature is 780 °C, and the holding time is 5 h. Remove the pore-forming agent by water bath and then dry it. Then carry out secondary sintering by plasma discharge sintering. The sintering temperature is 1300 °C, and the holding time is 4 h to obtain a three-dimensional porous high-entropy alloy;

[0085] S3. Clean the three-dimensional porous high-entropy alloy prepared in S2, put it into a plasma nitriding equipment, introduce a mixed atmosphere with a ratio of nitrogen to hydrogen of 1:2, and heat it to 500 °C for nitriding for 1.5 h, and then cool it to room temperature in the furnace to obtain a three-dimensional porous high-entropy alloy with a nitrided layer on its surface;

[0086] S4. Place the three-dimensional porous high-entropy alloy prepared in S3 at the bottom and the aluminum alloy on top in a crucible, evacuate it, heat it to 400 °C to preheat the three-dimensional porous high-entropy alloy, and then heat it to 720 °C to melt the aluminum alloy and fill it with argon for pressurization. Keep it at a constant temperature and pressure until infiltration is completed and then solidify it to obtain a three-dimensional porous high-entropy alloy reinforced aluminum matrix composite;

[0087] The composition of the aluminum alloy matrix consists of the following weight percentages: Zn: 5.62 wt%, Mg: 2.42 wt%, Cu: 1.64 wt%, Cr: 0.30 wt%, Fe: 0.04 wt%, Si: 0.09 wt%, and the balance is Al;

[0088] The composition of the three-dimensional porous high-entropy alloy is Ti 25Mg 20 Fe 20 Cr 15 Ni 15 La5, and 1% of Y2O3 was added.

[0089] Example 8:

[0090] A three-dimensional porous high-entropy alloy reinforced aluminum matrix composite material is composed of 65% aluminum alloy matrix and 35% three-dimensional porous high-entropy alloy. The three-dimensional porous high-entropy alloy is a three-dimensionally connected open-cell structure with a porosity of 65% and a nitrided layer with a thickness of 1 - 2 μm on the surface.

[0091] The preparation method of the three-dimensional porous high-entropy alloy reinforced aluminum matrix composite material includes the following steps:

[0092] S1. Prepare the raw material powders required for the high-entropy alloy according to the ratio, and carry out mechanical alloying ball milling to mix evenly. The ball milling speed is 320 r / min, and the ball milling time is 24 h. Add pore-forming agent NaCl particles with a particle size of 200 - 300 μm and binder absolute ethanol, and ball mill again to mix evenly and form a paste. The addition amount of the pore-forming agent is 125% of the volume of the metal powder, and the addition amount of the binder is 8% of the mass of the metal powder to obtain a uniform raw material.

[0093] S2. Put the raw material prepared in S1 into a mold, cold press and dry it, then put it into a vacuum sintering furnace for pre-sintering. The pre-sintering temperature is 780 °C, and the holding time is 5 h. Remove the pore-forming agent by water bath and dry it, and then carry out secondary sintering by plasma discharge sintering method. The sintering temperature is 1250 °C, and the holding time is 4 h to obtain a three-dimensional porous high-entropy alloy.

[0094] S3. Clean the three-dimensional porous high-entropy alloy prepared in S2, put it into a plasma nitriding equipment, introduce a mixed atmosphere with a ratio of nitrogen to hydrogen of 1:2, and heat it to 500 °C for nitriding for 1.5 h, and then cool it to room temperature in the furnace to obtain a three-dimensional porous high-entropy alloy with a nitrided layer on the surface.

[0095] S4. Place the three-dimensional porous high-entropy alloy prepared in S3 at the bottom and the aluminum alloy on top in a crucible, evacuate the vacuum, heat it to 400 °C to preheat the three-dimensional porous high-entropy alloy, and then heat it to 740 °C to melt the aluminum alloy and fill it with argon for pressurization. Keep the temperature and pressure until infiltration is completed and then solidify to obtain a three-dimensional porous high-entropy alloy reinforced aluminum matrix composite material.

[0096] The composition of the aluminum alloy matrix is composed of the following weight percentages: Zn: 5.62 wt%, Mg: 2.47 wt%, Cu: 1.55 wt%, Cr: 0.24 wt%, Fe: 0.12 wt%, Si: 0.08 wt%, and the balance is Al.

[0097] The composition of the three-dimensional porous high-entropy alloy is Ti 25 Mg 20 Fe 20 Cr 15 Ni 15 La5, and 1% of Y2O3 is added.

[0098] Example 9:

[0099] A three-dimensional porous high-entropy alloy reinforced aluminum matrix composite material is composed of 65% aluminum alloy matrix and 35% three-dimensional porous high-entropy alloy. The three-dimensional porous high-entropy alloy has a three-dimensionally connected open-cell structure, a porosity of 65%, and a 1-2 μm thick nitride layer on its surface;

[0100] The preparation method of the three-dimensional porous high-entropy alloy reinforced aluminum matrix composite material includes the following steps:

[0101] S1. Prepare the raw material powders required for the high-entropy alloy according to the proportion, and carry out mechanical alloying ball milling to mix them evenly. The ball milling speed is 320 r / min, and the ball milling time is 24 h. Add pore-forming agent NaCl particles with a particle size of 200-300 μm and binder anhydrous ethanol, and ball mill and mix them evenly again to form a paste. The addition amount of the pore-forming agent is 125% of the volume of the metal powder, and the addition amount of the binder is 8% of the mass of the metal powder to obtain a uniform raw material;

[0102] S2. Put the raw material prepared in S1 into a mold, cold press and form it, and dry it. Then put it into a vacuum sintering furnace for pre-sintering. The pre-sintering temperature is 780 °C, and the holding time is 5 h. Remove the pore-forming agent by water bath and dry it. Then carry out secondary sintering by plasma discharge sintering method. The sintering temperature is 1250 °C, and the holding time is 4 h to obtain a three-dimensional porous high-entropy alloy;

[0103] S3. Clean the three-dimensional porous high-entropy alloy prepared in S2, put it into a plasma nitriding device, introduce a mixed atmosphere with a ratio of nitrogen to hydrogen of 1:2, and heat it to 500 °C for nitriding for 1.5 h, and then cool it to room temperature in the furnace to obtain a three-dimensional porous high-entropy alloy with a nitride layer on its surface;

[0104] S4. Place the three-dimensional porous high-entropy alloy prepared in S3 at the bottom and the aluminum alloy at the top in a crucible, evacuate it, heat it to 400 °C to preheat the three-dimensional porous high-entropy alloy, and then heat it to 760 °C to melt the aluminum alloy and fill it with argon for pressurization. Keep the temperature and pressure until infiltration is completed and then solidify to obtain a three-dimensional porous high-entropy alloy reinforced aluminum matrix composite material;

[0105] The composition of the aluminum alloy matrix consists of the following weight percentages: Zn: 5.75 wt%, Mg: 2.28 wt%, Cu: 1.46 wt%, Cr: 0.29 wt%, Fe: 0.09 wt%, Si: 0.09 wt%, and the balance is Al;

[0106] The composition of the three-dimensional porous high-entropy alloy is Ti 25 Mg 20 Fe 20 Cr 15 Ni 15 La5, and 1% of Y2O3 is added.

[0107] Example 10:

[0108] A three-dimensional porous high-entropy alloy reinforced aluminum matrix composite is composed of 65% aluminum alloy matrix and 35% three-dimensional porous high-entropy alloy. The three-dimensional porous high-entropy alloy is a three-dimensionally connected open-cell structure with a porosity of 65% and a 1-2 μm thick nitride layer on its surface;

[0109] The preparation method of the three-dimensional porous high-entropy alloy reinforced aluminum matrix composite includes the following steps:

[0110] S1. Prepare the raw material powders required for the high-entropy alloy according to the ratio, and carry out mechanical alloying ball milling to mix them evenly. The ball milling speed is 320 r / min, and the ball milling time is 24 h. Add pore-forming agent NaCl particles with a particle size of 200-300 μm and binder anhydrous ethanol, and ball mill and mix them evenly again to form a paste. The addition amount of the pore-forming agent is 125% of the volume of the metal powder, and the addition amount of the binder is 8% of the mass of the metal powder to obtain a uniform raw material;

[0111] S2. Put the raw material prepared in S1 into a mold, cold press and form it, then dry it. Put it into a vacuum sintering furnace for pre-sintering. The pre-sintering temperature is 780 °C, and the holding time is 5 h. Remove the pore-forming agent by water bath and dry it. Then carry out secondary sintering by plasma discharge sintering method. The sintering temperature is 1250 °C, and the holding time is 4 h to obtain a three-dimensional porous high-entropy alloy;

[0112] S3. Clean the three-dimensional porous high-entropy alloy prepared in S2, put it into a plasma nitriding device, introduce a mixed atmosphere with a ratio of nitrogen to hydrogen of 1:2, and heat it to 500 °C for nitriding for 1.5 h, and then cool it to room temperature in the furnace to obtain a three-dimensional porous high-entropy alloy with a nitride layer on its surface;

[0113] S4. Place the three-dimensional porous high-entropy alloy prepared in S3 below and the aluminum alloy above in a crucible, evacuate it, heat the three-dimensional porous high-entropy alloy to 400 °C for preheating, and then heat it to 780 °C to melt the aluminum alloy and fill it with argon for pressurization. Keep the temperature and pressure until infiltration is completed and then solidify to obtain a three-dimensional porous high-entropy alloy reinforced aluminum matrix composite;

[0114] The composition of the aluminum alloy matrix consists of the following weight percentages: Zn: 5.69 wt%, Mg: 2.22 wt%, Cu: 1.56 wt%, Cr: 0.30 wt%, Fe: 0.14 wt%, Si: 0.03 wt%, and the balance is Al;

[0115] The composition of the three-dimensional porous high-entropy alloy is Ti 25 Mg 20 Fe 20 Cr 15 Ni 15 La5, and 1% of Y2O3 is added.

[0116] Example 11:

[0117] A three-dimensional porous high-entropy alloy reinforced aluminum matrix composite is composed of 65% aluminum alloy matrix and 35% three-dimensional porous high-entropy alloy. The three-dimensional porous high-entropy alloy is a three-dimensionally connected open-cell structure with a porosity of 65% and a 1-2 μm nitride layer on the surface;

[0118] The preparation method of the three-dimensional porous high-entropy alloy reinforced aluminum matrix composite includes the following steps:

[0119] S1. Prepare the raw material powders required for the high-entropy alloy according to the ratio, and carry out mechanical alloying ball milling to mix them evenly. The ball milling speed is 320 r / min, the ball milling time is 24 h. Add 200-300 μm pore-forming agent NaCl particles and binder anhydrous ethanol, and ball mill and mix evenly again to form a paste. The addition amount of the pore-forming agent is 125% of the volume of the metal powder, and the addition amount of the binder is 8% of the mass of the metal powder to obtain a uniform raw material;

[0120] S2. Put the raw material prepared in S1 into a mold, cold press and form it, and dry it. Put it into a vacuum sintering furnace for pre-sintering. The pre-sintering temperature is 760 °C, the heat preservation time is 5 h. Remove the pore-forming agent by water bath and dry it. Then carry out secondary sintering by plasma discharge sintering. The sintering temperature is 1250 °C, and the heat preservation time is 4 h to obtain a three-dimensional porous high-entropy alloy;

[0121] S3. Clean the three-dimensional porous high-entropy alloy prepared in S2, put it into a plasma nitriding device, introduce a mixed atmosphere of nitrogen and hydrogen with a ratio of 1:2, and heat it to 500 °C for nitriding for 1.5 h, then cool it to room temperature in the furnace to obtain a three-dimensional porous high-entropy alloy with a nitrided layer on the surface;

[0122] S4. Place the three-dimensional porous high-entropy alloy prepared in S3 below and aluminum alloy above in a crucible, evacuate it, heat it to 400 °C to preheat the three-dimensional porous high-entropy alloy, then heat it to 760 °C to melt the aluminum alloy and fill it with argon for pressurization, keep it warm and pressurized until infiltration is completed and then solidify to obtain a three-dimensional porous high-entropy alloy reinforced aluminum matrix composite;

[0123] The composition of the aluminum alloy matrix consists of the following weight percentages: Zn: 5.96 wt%, Mg: 2.05 wt%, Cu: 1.58 wt%, Cr: 0.17 wt%, Fe: 0.11 wt%, Si: 0.1 wt%, and the balance is Al;

[0124] The composition of the three-dimensional porous high-entropy alloy is Ti 25 Mg 20 Fe 20 Cr 15 Ni 15 La5, and 2% of Y2O3 is added.

[0125] Example 12:

[0126] A three-dimensional porous high-entropy alloy reinforced aluminum matrix composite is composed of 65% aluminum alloy matrix and 35% three-dimensional porous high-entropy alloy. The three-dimensional porous high-entropy alloy is a three-dimensionally connected open-cell structure with a porosity of 65% and a nitrided layer with a thickness of 1 - 2 μm on the surface;

[0127] The preparation method of the three-dimensional porous high-entropy alloy reinforced aluminum matrix composite includes the following steps:

[0128] S1. Prepare the raw material powders required for the high-entropy alloy according to the ratio, and carry out mechanical alloying ball milling to mix them evenly. The ball milling speed is 320 r / min, the ball milling time is 24 h. Add pore-forming agent NaCl particles with a particle size of 200 - 300 μm and binder absolute ethanol, and ball mill and mix them evenly again to form a paste. The addition amount of the pore-forming agent is 125% of the volume of the metal powder, and the addition amount of the binder is 8% of the mass of the metal powder to obtain a uniform raw material;

[0129] S2. Put the raw materials prepared in S1 into a mold, cold press and dry them, then put them into a vacuum sintering furnace for pre-sintering. The pre-sintering temperature is 760 °C, and the heat preservation time is 5 h. Remove the pore-forming agent by water bath and dry it. Then, perform secondary sintering by plasma discharge sintering. The sintering temperature is 1250 °C, and the heat preservation time is 4 h to obtain a three-dimensional porous high-entropy alloy.

[0130] S3. Clean the three-dimensional porous high-entropy alloy prepared in S2, put it into a plasma nitriding device, introduce a mixed atmosphere with a nitrogen-to-hydrogen ratio of 1:2, and heat it to 500 °C for nitriding for 1.5 h. Then cool it to room temperature in the furnace to obtain a three-dimensional porous high-entropy alloy with a nitrided layer on the surface.

[0131] S4. Place the three-dimensional porous high-entropy alloy prepared in S3 below and aluminum alloy above in a crucible, evacuate the vacuum, heat it to 400 °C to preheat the three-dimensional porous high-entropy alloy, and then heat it to 760 °C to melt the aluminum alloy and fill it with argon for pressurization. Keep the temperature and pressure until infiltration is completed and then solidify to obtain a three-dimensional porous high-entropy alloy reinforced aluminum matrix composite.

[0132] The composition of the aluminum alloy matrix consists of the following weight percentages: Zn: 5.94 wt%, Mg: 2.03 wt%, Cu: 1.35 wt%, Cr: 0.30 wt%, Fe: 0.06 wt%, Si: 0.05 wt%, and the balance is Al.

[0133] The composition of the three-dimensional porous high-entropy alloy is Ti 25 Mg 20 Fe 20 Cr 15 Ni 15 La5, and 3% of Y2O3 is added.

[0134] Example 13:

[0135] A three-dimensional porous high-entropy alloy reinforced aluminum matrix composite is composed of 65% aluminum alloy matrix and 35% three-dimensional porous high-entropy alloy. The three-dimensional porous high-entropy alloy is a three-dimensionally connected open-cell structure with a porosity of 65% and a nitrided layer with a thickness of 1 - 2 μm on the surface.

[0136] The preparation method of the three-dimensional porous high-entropy alloy reinforced aluminum matrix composite includes the following steps:

[0137] S1. Prepare the raw material powders required for the high-entropy alloy according to the proportion, and carry out mechanical alloying ball milling to mix evenly. The ball milling speed is 320 r / min, and the ball milling time is 24 h. Add pore-forming agent NaCl particles with a particle size of 200 - 300 μm and binder absolute ethanol, and ball mill again to mix evenly and form a paste. The addition amount of the pore-forming agent is 125% of the volume of the metal powder, and the addition amount of the binder is 8% of the mass of the metal powder to obtain a uniform raw material;

[0138] S2. Put the raw material prepared in S1 into a mold for cold pressing and drying, and then put it into a vacuum sintering furnace for pre-sintering. The pre-sintering temperature is 760 °C, and the holding time is 5 h. Remove the pore-forming agent by water bath and dry it. Then, perform secondary sintering by plasma discharge sintering. The sintering temperature is 1250 °C, and the holding time is 4 h to obtain a three-dimensional porous high-entropy alloy;

[0139] S3. Clean the three-dimensional porous high-entropy alloy prepared in S2, put it into a plasma nitriding equipment, introduce a mixed atmosphere with a ratio of nitrogen to hydrogen of 1:2, and heat it to 500 °C for nitriding for 1.5 h, and then cool it to room temperature in the furnace to obtain a three-dimensional porous high-entropy alloy with a nitrided layer on the surface;

[0140] S4. Place the three-dimensional porous high-entropy alloy prepared in S3 below and aluminum alloy above in a crucible, evacuate the vacuum, heat it to 400 °C to preheat the three-dimensional porous high-entropy alloy, and then heat it to 760 °C to melt the aluminum alloy and fill it with argon for pressurization. Keep the temperature and pressure until infiltration is completed and then solidify to obtain a three-dimensional porous high-entropy alloy reinforced aluminum matrix composite;

[0141] The composition of the aluminum alloy matrix consists of the following weight percentages: Zn: 5.86 wt%, Mg: 2.44 wt%, Cu: 1.52 wt%, Cr: 0.19 wt%, Fe: 0.05 wt%, Si: 0.01 wt%, and the balance is Al;

[0142] The composition of the three-dimensional porous high-entropy alloy is Ti 25 Mg 20 Fe 20 Cr 15 Ni 15 La5, and 4% of Y2O3 is added.

[0143] Example 14:

[0144] A three-dimensional porous high-entropy alloy reinforced aluminum matrix composite consists of 65% aluminum alloy matrix and 35% three-dimensional porous high-entropy alloy. Among them, the three-dimensional porous high-entropy alloy is a three-dimensionally connected open-cell structure, the porosity is 65%, and there is a 1 - 2 μm nitrided layer on the surface;

[0145] The preparation method of the three-dimensional porous high-entropy alloy reinforced aluminum matrix composite material comprises the following steps:

[0146] S1. Prepare the raw material powders required for the high-entropy alloy according to the proportion, and carry out mechanical alloying ball milling to mix evenly. The ball milling speed is 320 r / min, and the ball milling time is 24 h. Add pore-forming agent NaCl particles with a particle size of 200 - 300 μm and binder absolute ethanol, and ball mill and mix evenly again to form a paste. The addition amount of the pore-forming agent is 125% of the volume of the metal powder, and the addition amount of the binder is 8% of the mass of the metal powder to obtain a uniform raw material;

[0147] S2. Put the raw material prepared in S1 into a mold, cold press and form it, and then dry it. Put it into a vacuum sintering furnace for pre-sintering. The pre-sintering temperature is 760 °C, and the heat preservation time is 5 h. Remove the pore-forming agent by water bath and dry it. Then, carry out secondary sintering by plasma discharge sintering method. The sintering temperature is 1250 °C, and the heat preservation time is 4 h to obtain a three-dimensional porous high-entropy alloy;

[0148] S3. Clean the three-dimensional porous high-entropy alloy prepared in S2, put it into a plasma nitriding device, introduce a mixed atmosphere with a ratio of nitrogen to hydrogen of 1:2, and heat it to 500 °C for nitriding for 1.5 h, and then cool it to room temperature in the furnace to obtain a three-dimensional porous high-entropy alloy with a nitrided layer on the surface;

[0149] S4. Place the three-dimensional porous high-entropy alloy prepared in S3 at the bottom and aluminum alloy at the top in a crucible, evacuate it, heat it to 400 °C to preheat the three-dimensional porous high-entropy alloy, and then heat it to 760 °C to melt the aluminum alloy and fill it with argon for pressurization. Keep the temperature and pressure until infiltration is completed and then solidify to obtain a three-dimensional porous high-entropy alloy reinforced aluminum matrix composite material;

[0150] The composition of the aluminum alloy matrix consists of the following weight percentages: Zn: 5.53 wt%, Mg: 2.08 wt%, Cu: 1.62 wt%, Cr: 0.32 wt%, Fe: 0.13 wt%, Si: 0.04 wt%, and the balance is Al;

[0151] The composition of the three-dimensional porous high-entropy alloy is Ti 25 Mg 20 Fe 20 Cr 15 Ni 15 La5, and 5% of Y2O3 is added.

[0152] To further illustrate the technical effects of the present invention, the present invention also sets a comparative example, which is specifically as follows:

[0153] Comparative example 1:

[0154] An aluminum matrix composite material is composed of 50% aluminum alloy matrix and 50% three-dimensional porous high-entropy alloy. The three-dimensional porous high-entropy alloy is a three-dimensionally connected open-cell structure with a porosity of 50%, and has a nitrided layer with a thickness of 1 - 2 μm on its surface;

[0155] The preparation method of the aluminum matrix composite material includes the following steps:

[0156] S1. Prepare the raw material powders required for the high-entropy alloy according to the proportion, and carry out mechanical alloying ball milling to mix evenly. The ball milling speed is 320 r / min, and the ball milling time is 24 h. Add pore-forming agent NaCl particles with a particle size of 200 - 300 μm and binder anhydrous ethanol, and ball mill and mix evenly again to form a paste. The addition amount of the pore-forming agent is 70% of the volume of the metal powder, and the addition amount of the binder is 8% of the mass of the metal powder, to obtain a uniform raw material;

[0157] S2. Put the raw material prepared in S1 into a mold for cold pressing and forming, then dry it, and put it into a vacuum sintering furnace for pre-sintering. The pre-sintering temperature is 780 °C, and the holding time is 5 h. Remove the pore-forming agent by water bath and dry it, and then carry out secondary sintering by plasma discharge sintering method. The sintering temperature is 1100 °C, and the holding time is 4 h, to obtain a three-dimensional porous high-entropy alloy;

[0158] S3. Clean the three-dimensional porous high-entropy alloy prepared in S2, put it into a plasma nitriding equipment, introduce a mixed atmosphere with a ratio of nitrogen to hydrogen of 1:2, and heat it to 500 °C for nitriding for 1.5 h, and then cool it to room temperature in the furnace, to obtain a three-dimensional porous high-entropy alloy with a nitrided layer on its surface;

[0159] S4. Place the three-dimensional porous high-entropy alloy prepared in S3 at the bottom and the aluminum alloy at the top in a crucible, evacuate the air, heat it to 400 °C to preheat the three-dimensional porous high-entropy alloy, and then heat it to 720 °C to melt the aluminum alloy and fill it with argon for pressurization. Keep the temperature and pressure until infiltration is completed and then solidify, to obtain the aluminum matrix composite material;

[0160] The composition of the aluminum alloy matrix is composed of the following weight percentages: Zn: 5.89 wt%, Mg: 2.06 wt%, Cu: 1.66 wt%, Cr: 0.27 wt%, Fe: 0.08 wt%, Si: 0.05 wt%, and the balance is Al;

[0161] The composition of the three-dimensional porous high-entropy alloy is Ti 25 Mg 20 Fe 20 Cr 15 Ni 15 La5, and 1% of Y2O3 is added.

[0162] Comparative Example 2:

[0163] An aluminum matrix composite material is composed of 65% aluminum alloy matrix and 35% three-dimensional porous high-entropy alloy. The three-dimensional porous high-entropy alloy has a three-dimensionally connected open-cell structure, a porosity of 65%, and a 1-2 μm thick nitride layer on its surface.

[0164] The preparation method of the aluminum matrix composite material includes the following steps:

[0165] S1. Prepare the raw material powders required for the high-entropy alloy according to the ratio, and carry out mechanical alloying ball milling to mix them evenly. The ball milling speed is 320 r / min, and the ball milling time is 24 h. Add 200-300 μm diameter pore-forming agent NaCl particles and binder absolute ethanol, and ball mill and mix evenly again to form a paste. The addition amount of the pore-forming agent is 125% of the volume of the metal powder, and the addition amount of the binder is 8% of the mass of the metal powder to obtain a uniform raw material.

[0166] S2. Put the raw material prepared in S1 into a mold, cold press and form it, and then dry it. Put it into a vacuum sintering furnace for pre-sintering. The pre-sintering temperature is 780 °C, and the holding time is 5 h. Remove the pore-forming agent by water bath and dry it. Then carry out secondary sintering by plasma discharge sintering method. The sintering temperature is 1000 °C, and the holding time is 4 h to obtain a three-dimensional porous high-entropy alloy.

[0167] S3. Clean the three-dimensional porous high-entropy alloy prepared in S2, put it into a plasma nitriding equipment, introduce a mixed atmosphere with a ratio of nitrogen to hydrogen of 1:2, and heat it to 500 °C for nitriding for 1.5 h, and then cool it to room temperature in the furnace to obtain a three-dimensional porous high-entropy alloy with a nitride layer on its surface.

[0168] S4. Place the three-dimensional porous high-entropy alloy prepared in S3 at the bottom and the aluminum alloy on top in a crucible, evacuate the air, heat it to 400 °C to preheat the three-dimensional porous high-entropy alloy, and then heat it to 720 °C to melt the aluminum alloy and fill it with argon under pressure. Hold the temperature and pressure until infiltration is completed and then solidify to obtain the aluminum matrix composite material.

[0169] The composition of the aluminum alloy matrix is composed of the following weight percentages: Zn: 5.55 wt%, Mg: 2.27 wt%, Cu: 1.43 wt%, Cr: 0.25 wt%, Fe: 0.15 wt%, Si: 0.05 wt%, and the balance is Al.

[0170] The composition of the three-dimensional porous high-entropy alloy is Ti 25 Mg 20 Fe 20 Cr 15 Ni 15 La5, and 1% of Y2O3 is added.

[0171] Comparative Example 3:

[0172] An aluminum matrix composite material is composed of 65% aluminum alloy matrix and 35% three-dimensional porous high-entropy alloy. The three-dimensional porous high-entropy alloy is a three-dimensionally connected open-cell structure with a porosity of 65%, and has a nitrided layer with a thickness of 1 - 2 μm on its surface;

[0173] The preparation method of the aluminum matrix composite material includes the following steps:

[0174] S1. Prepare the raw material powders required for the high-entropy alloy according to the proportion, and carry out mechanical alloying ball milling to mix evenly. The ball milling speed is 320 r / min, the ball milling time is 24 h. Add pore-forming agent NaCl particles with a particle size of 200 - 300 μm and binder absolute ethanol, and ball mill again to mix evenly and form a paste. The addition amount of the pore-forming agent is 125% of the volume of the metal powder, and the addition amount of the binder is 8% of the mass of the metal powder to obtain a uniform raw material;

[0175] S2. Put the raw material prepared in S1 into a mold, cold press and dry it, then put it into a vacuum sintering furnace for pre-sintering. The pre-sintering temperature is 780 °C, the heat preservation time is 5 h. Remove the pore-forming agent by water bath and dry it, and then carry out secondary sintering by plasma discharge sintering method. The sintering temperature is 1250 °C, and the heat preservation time is 4 h to obtain a three-dimensional porous high-entropy alloy;

[0176] S3. Clean the three-dimensional porous high-entropy alloy prepared in S2, put it into a plasma nitriding equipment, introduce a mixed atmosphere with a ratio of nitrogen to hydrogen of 1:2, and heat it to 500 °C for nitriding for 1.5 h, and then cool it to room temperature in the furnace to obtain a three-dimensional porous high-entropy alloy with a nitrided layer on its surface;

[0177] S4. Place the three-dimensional porous high-entropy alloy prepared in S3 at the bottom and aluminum alloy on the top in a crucible, evacuate the vacuum, heat it to 400 °C to preheat the three-dimensional porous high-entropy alloy, and then heat it to 700 °C to melt the aluminum alloy and fill it with argon for pressurization. Keep the temperature and pressure until infiltration is completed and then solidify to obtain an aluminum matrix composite material;

[0178] The composition of the aluminum alloy matrix is composed of the following weight percentages: Zn: 5.82 wt%, Mg: 2.37 wt%, Cu: 1.45 wt%, Cr: 0.19 wt%, Fe: 0.12 wt%, Si: 0.1 wt%, and the balance is Al;

[0179] The composition of the three-dimensional porous high-entropy alloy is Ti 25 Mg 20 Fe 20 Cr 15 Ni 15La5, with 1% of Y2O3 added.

[0180] Comparative Example 4:

[0181] An aluminum matrix composite material is composed of 65% aluminum alloy matrix and 35% three-dimensional porous high-entropy alloy. The three-dimensional porous high-entropy alloy is a three-dimensionally connected open-cell structure with a porosity of 65%, and has a 1-2 μm thick nitride layer on its surface;

[0182] The preparation method of the aluminum matrix composite material includes the following steps:

[0183] S1. Prepare the raw material powders required for the high-entropy alloy according to the ratio, and carry out mechanical alloying ball milling to mix them evenly. The ball milling speed is 320 r / min, and the ball milling time is 24 h. Add 200-300 μm diameter pore-forming agent NaCl particles and binder anhydrous ethanol, and ball mill and mix evenly again to form a paste. The addition amount of the pore-forming agent is 125% of the volume of the metal powder, and the addition amount of the binder is 8% of the mass of the metal powder to obtain a uniform raw material;

[0184] S2. Put the raw material prepared in S1 into a mold, cold press and form it, then dry it, put it into a vacuum sintering furnace for pre-sintering. The pre-sintering temperature is 780 °C, and the holding time is 5 h. Remove the pore-forming agent by water bath and dry it, and then carry out secondary sintering by plasma discharge sintering. The sintering temperature is 1250 °C, and the holding time is 4 h to obtain a three-dimensional porous high-entropy alloy;

[0185] S3. Clean the three-dimensional porous high-entropy alloy prepared in S2, put it into a plasma nitriding equipment, introduce a mixed atmosphere with a ratio of nitrogen to hydrogen of 1:2, and heat it to 500 °C for nitriding for 1.5 h, and then cool it to room temperature in the furnace to obtain a three-dimensional porous high-entropy alloy with a nitride layer on its surface;

[0186] S4. Place the three-dimensional porous high-entropy alloy prepared in S3 at the bottom and the aluminum alloy on top in a crucible, evacuate it, heat it to 400 °C to preheat the three-dimensional porous high-entropy alloy, and then heat it to 800 °C to melt the aluminum alloy and fill it with argon for pressurization. Keep the temperature and pressure until infiltration is completed and then solidify to obtain the aluminum matrix composite material;

[0187] The composition of the aluminum alloy matrix consists of the following weight percentages: Zn: 5.67 wt%, Mg: 2.21 wt%, Cu: 1.47 wt%, Cr: 0.29 wt%, Fe: 0.13 wt%, Si: 0.05 wt%, and the balance is Al;

[0188] The composition of the three-dimensional porous high-entropy alloy is Ti 25 Mg 20 Fe 20 Cr 15Ni 15 La5, with 1% of Y2O3 added.

[0189] Comparative Example 5:

[0190] An aluminum matrix composite material is composed of 65% aluminum alloy matrix and 35% three-dimensional porous high-entropy alloy. The three-dimensional porous high-entropy alloy has a three-dimensionally connected open-cell structure, a porosity of 65%, and a 1-2 μm thick nitride layer on its surface.

[0191] The preparation method of the aluminum matrix composite material includes the following steps:

[0192] S1. Prepare the raw material powders required for the high-entropy alloy according to the ratio, and carry out mechanical alloying ball milling to mix them evenly. The ball milling speed is 320 r / min, and the ball milling time is 24 h. Add 200-300 μm diameter pore-forming agent NaCl particles and binder anhydrous ethanol, and ball mill again to mix evenly and form a paste. The addition amount of the pore-forming agent is 125% of the volume of the metal powder, and the addition amount of the binder is 8% of the mass of the metal powder to obtain a uniform raw material.

[0193] S2. Put the raw material prepared in S1 into a mold, cold press and dry it, then put it into a vacuum sintering furnace for pre-sintering. The pre-sintering temperature is 760 °C, and the holding time is 5 h. Remove the pore-forming agent by water bath and dry it, and then carry out secondary sintering by plasma discharge sintering method. The sintering temperature is 1250 °C, and the holding time is 4 h to obtain a three-dimensional porous high-entropy alloy.

[0194] S3. Clean the three-dimensional porous high-entropy alloy prepared in S2, put it into a plasma nitriding equipment, introduce a mixed atmosphere with a ratio of nitrogen to hydrogen of 1:2, and heat it to 500 °C for nitriding for 1.5 h, and then cool it to room temperature in the furnace to obtain a three-dimensional porous high-entropy alloy with a nitride layer on its surface.

[0195] S4. Place the three-dimensional porous high-entropy alloy prepared in S3 at the bottom and the aluminum alloy on top in a crucible, evacuate it, heat it to 400 °C to preheat the three-dimensional porous high-entropy alloy, and then heat it to 760 °C to melt the aluminum alloy and fill it with argon for pressurization. Keep the temperature and pressure until infiltration is completed and then solidify to obtain the aluminum matrix composite material.

[0196] The composition of the aluminum alloy matrix consists of the following weight percentages: Zn: 5.78 wt%, Mg: 2.47 wt%, Cu: 1.62 wt%, Cr: 0.21 wt%, Fe: 0.15 wt%, Si: 0.08 wt%, and the balance is Al.

[0197] The composition of the three-dimensional porous high-entropy alloy is Ti 25 Mg 20 Fe 20Cr 15 Ni 15 La5, and 7% of Y2O3 was added.

[0198] Comparative Example 6:

[0199] An aluminum matrix composite material is composed of 65% aluminum alloy matrix and 35% three-dimensional porous high-entropy alloy. The three-dimensional porous high-entropy alloy is a three-dimensionally connected open-cell structure with a porosity of 65%, and has a nitrided layer with a thickness of 1 - 2 μm on the surface;

[0200] The preparation method of the aluminum matrix composite material includes the following steps:

[0201] S1. Prepare the raw material powders required for the high-entropy alloy according to the ratio, and carry out mechanical alloying ball milling to mix evenly. The ball milling speed is 320 r / min, the ball milling time is 24 h. Add pore-forming agent NaCl particles with a particle size of 200 - 300 μm and binder absolute ethanol, and ball mill again to mix evenly and form a paste. The addition amount of the pore-forming agent is 125% of the volume of the metal powder, and the addition amount of the binder is 8% of the mass of the metal powder to obtain a uniform raw material;

[0202] S2. Put the raw material prepared in S1 into a mold, cold press and dry it, then put it into a vacuum sintering furnace for pre-sintering. The pre-sintering temperature is 760 °C, and the holding time is 5 h. Remove the pore-forming agent by water bath and dry it, and then carry out secondary sintering by plasma discharge sintering method. The sintering temperature is 1250 °C, and the holding time is 4 h to obtain a three-dimensional porous high-entropy alloy;

[0203] S3. Clean the three-dimensional porous high-entropy alloy prepared in S2, put it into a plasma nitriding equipment, introduce a mixed atmosphere with a ratio of nitrogen to hydrogen of 1:2, and heat it to 500 °C for nitriding for 1.5 h, and then cool it to room temperature in the furnace to obtain a three-dimensional porous high-entropy alloy with a nitrided layer on the surface;

[0204] S4. Place the three-dimensional porous high-entropy alloy prepared in S3 at the bottom and the aluminum alloy on top in a crucible, evacuate the air, heat it to 400 °C to preheat the three-dimensional porous high-entropy alloy, and then heat it to 760 °C to melt the aluminum alloy and fill it with argon for pressurization. Keep the temperature and pressure until infiltration is completed and then solidify to obtain the aluminum matrix composite material;

[0205] The composition of the aluminum alloy matrix consists of the following weight percentages: Zn: 5.79 wt%, Mg: 2.34 wt%, Cu: 1.55 wt%, Cr: 0.26 wt%, Fe: 0.07 wt%, and the balance is Al;

[0206] The composition of the three-dimensional porous high-entropy alloy is Ti 25 Mg 20 Fe20 Cr 15 Ni 15 La5

[0207] Comparative Example 7:

[0208] An aluminum matrix composite material is composed of 65% aluminum alloy matrix and 35% three-dimensional porous high-entropy alloy. The three-dimensional porous high-entropy alloy is a three-dimensionally connected open-cell structure with a porosity of 65%.

[0209] The preparation method of the aluminum matrix composite material includes the following steps:

[0210] S1. Prepare the raw material powders required for the high-entropy alloy according to the ratio, and carry out mechanical alloying ball milling to mix evenly. The ball milling speed is 320 r / min, and the ball milling time is 24 h. Add pore-forming agent NaCl particles with a particle size of 200 - 300 μm and binder absolute ethanol, and ball mill again to mix evenly and form a paste. The addition amount of the pore-forming agent is 125% of the volume of the metal powder, and the addition amount of the binder is 8% of the mass of the metal powder to obtain a uniform raw material.

[0211] S2. Put the raw material prepared in S1 into a mold, cold press and dry it, then put it into a vacuum sintering furnace for pre-sintering. The pre-sintering temperature is 760 °C, and the holding time is 5 h. Remove the pore-forming agent by water bath and dry it, and then carry out secondary sintering by plasma discharge sintering. The sintering temperature is 1250 °C, and the holding time is 4 h to obtain a three-dimensional porous high-entropy alloy.

[0212] S3. Place the three-dimensional porous high-entropy alloy prepared in S2 at the bottom and the aluminum alloy on top in a crucible, evacuate, heat to 400 °C to preheat the three-dimensional porous high-entropy alloy, and then heat to 760 °C to melt the aluminum alloy and fill it with argon for pressurization. Hold the pressure until infiltration is completed and then solidify to obtain the aluminum matrix composite material.

[0213] The composition of the aluminum alloy matrix consists of the following weight percentages: Zn: 5.94 wt%, Mg: 2.03 wt%, Cu: 1.35 wt%, Cr: 0.30 wt%, Fe: 0.06 wt%, Si: 0.05 wt%, and the balance is Al.

[0214] The composition of the three-dimensional porous high-entropy alloy is Ti 25 Mg 20 Fe 20 Cr 15 Ni 15 La5, and 3% of Y2O3 is added.

[0215] The examples and comparative examples were prepared into standard specimens with a circular cross-section, and tensile tests were carried out using a universal testing machine. The test method of the tensile test was carried out according to the GB / T 228.1-2021 standard, and the hardness was tested with a microhardness tester. The results are shown in Tables 1 to 5.

[0216] Table 1 Effects of different volume fractions of reinforcing phases on the properties of aluminum matrix composites

[0217]

[0218] Table 2 Effects of different sintering temperatures of porous high-entropy alloys on the properties of aluminum matrix composites

[0219]

[0220] Table 3 Effects of different melting casting temperatures on the properties of aluminum matrix composites

[0221]

[0222] Table 4 Effects of different addition amounts of Y2O3 on the properties of aluminum matrix composites

[0223]

[0224] Table 5 Effects of the nitrided layer on the properties of aluminum matrix composites

[0225]

[0226] In summary, all the examples of the present invention have high strength and high hardness, excellent comprehensive mechanical properties, and broad application prospects.

Claims

1. A three-dimensional porous high entropy alloy reinforced aluminum-based composite material, characterized in that: The aluminum-based composite material is composed of 60-70% aluminum alloy matrix and 30-40% three-dimensional porous high-entropy alloy, wherein the three-dimensional porous high-entropy alloy is a three-dimensionally connected open-pore structure with a porosity of 60-70% and a 1-2 μm nitride layer on the surface, wherein the composition of the three-dimensional porous high-entropy alloy is Ti 20-25 Mg 20-25 Fe 15-20 Cr 15-20 Ni 10-15 La 5-10 , and 1 ~ 5% Y2O3 was added.

2. The method for preparing the three-dimensional porous high entropy alloy reinforced aluminum-based composite material according to claim 1, characterized in that: The following steps are involved: S1. The raw material powders required for the high entropy alloy are prepared in proportion, and are evenly mixed by mechanical alloying and ball milling. The pore former and the binder are evenly mixed by ball milling again and become a paste to obtain a uniform raw material; S2. The raw material prepared in S1 is placed in a mold, cold pressed and dried, placed in a vacuum sintering furnace for pre-sintering, the pore-forming agent is removed in a water bath and dried, and then secondary sintered by plasma discharge sintering to obtain a three-dimensional porous high entropy alloy; S3. The three-dimensional porous high entropy alloy prepared in S2 is cleaned, placed in a plasma nitriding device, introduced into a mixed atmosphere of hydrogen and nitrogen and heated for nitridation, and then cooled to room temperature to obtain a three-dimensional porous high entropy alloy having a nitrided layer on the surface; S4. Place the three-dimensional porous high entropy alloy prepared in S3 at the bottom and the aluminum alloy at the top in a crucible and evacuate the crucible, preheat the three-dimensional porous high entropy alloy, then heat to melt the aluminum alloy and fill it with argon to pressurize it, maintain the temperature and pressure until the infiltration is completed and then solidify to obtain a three-dimensional porous high entropy alloy reinforced aluminum-based composite material.

3. The method for preparing the three-dimensional porous high entropy alloy reinforced aluminum-based composite material according to claim 2, characterized in that: The mechanical alloying ball milling speed in step S1 is 300 to 350 r / min, and the ball milling time is 20 to 24 h.

4. The method for preparing the three-dimensional porous high entropy alloy reinforced aluminum-based composite material according to claim 2, characterized in that: In step S1, the pore-forming agent is NaCl, the particle size is 200-300 μm, and the amount of NaCl added is 100-150% of the volume of the metal powder; the binder is anhydrous ethanol, and the amount of anhydrous ethanol added is 7-10% of the mass of the metal powder.

5. The method for preparing the three-dimensional porous high entropy alloy reinforced aluminum-based composite material according to claim 2, characterized in that: In step S2, the pre-sintering temperature is 750-800 °C, and the holding time is 4-6 h; the secondary sintering temperature is 1100-1300 °C, and the holding time is 3-5 h.

6. The method for preparing the three-dimensional porous high entropy alloy reinforced aluminum-based composite material according to claim 2, characterized in that: The heating temperature in step S3 is 480-520° C., the nitriding time is 1-2 h, and the ratio of nitrogen to hydrogen in the mixed atmosphere is 1:1-2.

7. The method for preparing the three-dimensional porous high entropy alloy reinforced aluminum-based composite material according to claim 2, characterized in that: In step S4, the preheating temperature of the three-dimensional porous high entropy alloy is 400-420°C, and the heating temperature of the molten aluminum alloy is 720-780°C.

8. The three-dimensional porous high entropy alloy reinforced aluminum-based composite material according to claim 1, characterized in that: The components of the aluminum alloy matrix are composed of the following weight percentages: Zn: 5.5 ~ 6.0 wt%, Mg: 2.0 ~ 2.5 wt%, Cu: 1.3 ~1.7 wt%, Cr: 0.15 ~ 0.33 wt%, Fe: ≤0.15 wt%, Si: ≤0.1 wt%, and the balance is Al.

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