CuCrNi x TiZr high-entropy alloy and preparation method thereof

Abstract

The application discloses CuCrNi x TiZr high-entropy alloy and a preparation method thereof, and the specific process is as follows: raw materials Cu, Cr, Ni, Ti and Zr are weighed; the weighed raw materials are sequentially placed into a vacuum arc melting furnace in the order of Cu, Ni, Ti, Zr and Cr, and the furnace door is closed; a vacuum pump is opened to perform vacuumizing, a gas filling valve is opened to fill high-purity argon into the hearth of the vacuum arc melting furnace; arc striking and melting are started, and the CuCrNi x TiZr high-entropy alloy ingot is obtained after furnace cooling. x TiZr high-entropy alloy ingot is obtained after furnace cooling. x TiZr high-entropy alloy material. The prepared CuCrNi x TiZr high-entropy alloy material has good strength, very high hardness, better plasticity and good high-temperature resistance at room temperature.

Description

Technical Field

[0001] This invention belongs to the field of high-entropy alloys and high-entropy amorphous materials, specifically relating to CuCrNi x TiZr high-entropy alloys, also involving CuCrNi x Preparation method of TiZr high-entropy alloy. Background Technology

[0002] In recent years, the development of the aerospace and machinery industries has significantly increased the demand for high-performance materials. Compared to traditional alloys, high-entropy alloys are composed of elements with multiple principal components in equal or near-equal atomic ratios, exhibiting higher hardness, strength, corrosion resistance, high-temperature resistance, and thermal stability. Current research has found that CoCrNi-based high-entropy alloys have excellent high-temperature performance and ductility, making them a popular high-entropy alloy system. However, most CoCrNi-based high-entropy alloys exhibit an FCC structure, possessing good ductility but low strength. For example, while FeCoNiCr high-entropy alloys have an elongation exceeding 52% during room temperature tensile testing, their yield strength and tensile strength are only 162.2 MPa and 368.1 MPa, respectively. Amorphous alloys, as emerging advanced materials, possess higher hardness and strength due to their unique structural characteristics—short-range order and long-range disorder in atomic arrangement. To address these issues, researchers have combined the design concepts of high-entropy alloys with those of amorphous alloys, designing a novel high-entropy amorphous material that integrates the multi-principal component characteristics of high-entropy alloys with the structural characteristics of amorphous materials, exhibiting unique properties.

[0003] However, high-entropy amorphous materials, due to their dense atomic arrangement, tend to form large atomic clusters, making plastic deformation difficult. While these alloys possess higher strength and hardness, they also become more brittle. For example, research has found that Ti... 20 Zr 20 Cu 20 Ni 20 Be 20 The fracture strength can reach 2300 MPa, while exhibiting almost no compressive plasticity at room temperature. Current research on high-entropy amorphous materials focuses on Ti. 20 Zr 20 Hf 20 Cu 20 B e20 Ti 20 Zr 20 Ni 20 Cu 20 Be 20 Such systems possess high strength but extremely low plasticity. Therefore, it is essential to prepare a high-entropy alloy that combines the high strength of high-entropy amorphous materials with good plasticity. Summary of the Invention

[0004] The purpose of this invention is to provide CuCrNi x TiZr high-entropy alloys solve the problem that existing high-entropy alloys cannot simultaneously achieve high strength and ductility.

[0005] Another object of the present invention is to provide CuCrNi x Preparation method of TiZr high-entropy alloy.

[0006] The technical solution adopted in this invention is CuCrNi x The TiZr high-entropy alloy is composed of Cu, Cr, Ni, Ti, and Zr; the atomic ratio of Cu, Cr, Ni, Ti, and Zr is 1:1:x:1:1.

[0007] The invention is further characterized in that,

[0008] Furthermore, x = 0.1 to 10.

[0009] Furthermore, the purity of Ti, Zr, and Cr is 95% to 99.99%, and the purity of Ni and Cu is 99.9% to 99.99%.

[0010] Furthermore, CuCrNi x The TiZr high-entropy alloy consists of FCC and BCC phase structures.

[0011] The technical solution adopted in this invention is CuCrNi x The preparation method of TiZr high-entropy alloy is carried out according to the following steps:

[0012] Step 1: Clean the Cu, Cr, Ni, Ti, and Zr elements by weighing the raw materials Cu, Cr, Ni, Ti, and Zr. The atomic ratio of Cu, Cr, Ni, Ti, and Zr is 1:1:x:1:1, where x = 0.1 to 10.

[0013] Step 2: Place the raw materials weighed in Step 1 into the water-cooled copper crucible in the vacuum arc melting furnace in the order of Cu, Ni, Ti, Zr, Cr. Then place a separate pure Ti block in another crucible and close the furnace door.

[0014] Step 3: Turn on the vacuum pump to evacuate until the vacuum level is below 5.5 × 10⁻⁶. -3 MPa, open the charging valve to charge high-purity argon gas into the furnace of the vacuum arc melting furnace to 5×10 MPa. -2 MPa, then evacuate to 5.5 × 10 MPa again. -3 MPa, then refill with high-purity argon gas to 5×10. -2 MPa;

[0015] Step 4: Begin arc ignition and melting. After melting, cool in the furnace to obtain CuCrNi.x TiZr high-entropy alloy ingots;

[0016] Step 5, the CuCrNi obtained in step 4 x TiZr high-entropy alloy ingots are placed in a vacuum tube furnace for homogenization annealing, followed by furnace cooling to obtain CuCrNi. x TiZr high-entropy alloy materials.

[0017] The invention is further characterized in that,

[0018] In step 1, the cleaning process is as follows: the surface of Cu, Cr, Ni, Ti and Zr elements is polished to remove surface impurities and oxides, and then ultrasonically cleaned in industrial-grade ethanol for 5 min to 30 min, and then dried.

[0019] In step 4, the smelting process is as follows: First, the pure Ti block is smelted to deplete the residual oxygen in the furnace. The smelting current is 200A to 300A. Then, the Cu, Ni, Ti, Zr, and Cr elements in the water-cooled copper crucible are smelted. The smelting current is 280A to 400A to obtain a mixed liquid. The mixed liquid is smelted repeatedly 3 to 10 times. Each smelting time is 5 to 15 minutes. The sample needs to be turned over after each smelting.

[0020] In step 5, the homogenization annealing temperature is 400℃~1200℃, and the holding time is 2h~26h.

[0021] The beneficial effects of this invention are:

[0022] (1) The present invention CuCrNi x TiZr high-entropy alloy is mainly composed of FCC phase and BCC phase structure. The alloy has a uniform structure. Compared with traditional amorphous alloys, it has good strength, very high hardness, good plasticity and good high temperature resistance at room temperature. It is environmentally friendly and has a very broad application prospect.

[0023] (2) The CuCrNi of this invention x The preparation method of TiZr high-entropy alloy is to prepare high-strength, high-hardness, excellent plasticity and corrosion resistance high-entropy alloy materials through vacuum arc melting. The preparation method is simple and stable. On the one hand, it enriches the theoretical system of high-entropy alloys, and on the other hand, it optimizes the mechanical properties of alloys, which is of positive significance for promoting the practical application of high-entropy alloys.

[0024] (3) The CuCrNi of this invention x The preparation method of TiZr high-entropy alloy involves using a vacuum tube furnace to perform homogenization annealing heat treatment on the high-entropy alloy, which makes the microstructure and composition of the high-entropy alloy more uniform and fine, and improves its strength and plasticity. Attached Figure Description

[0025] Figure 1 This is a low-magnification microstructure of the CuCrNi0.5TiZr high-entropy alloy prepared in Example 2 of this invention;

[0026] Figure 2 The image shows the SEM morphology of the CuCrNi0.5TiZr high-entropy alloy prepared in Example 2 of this invention.

[0027] Figure 3 This is a low-magnification microstructure of the CuCrNi1.0TiZr high-entropy alloy prepared in Example 3 of this invention;

[0028] Figure 4 The image shows the SEM morphology of the CuCrNi1.0TiZr high-entropy alloy prepared in Example 3 of this invention.

[0029] Figure 5 This is a low-magnification microstructure of the CuCrNi1.5TiZr high-entropy alloy prepared in Example 4 of this invention;

[0030] Figure 6 The image shows the SEM morphology of the CuCrNi1.5TiZr high-entropy alloy prepared in Example 4 of this invention.

[0031] Figure 7 This is a low-magnification microstructure of the CuCrNi2.0TiZr high-entropy alloy prepared in Example 5 of this invention;

[0032] Figure 8 The image shows the SEM morphology of the CuCrNi2.0TiZr high-entropy alloy prepared in Example 5 of this invention.

[0033] Figure 9 The images show the XRD patterns of the alloy microstructures in Examples 2 and 5 of this invention.

[0034] Figure 10 These are the stress-strain curves of Examples 2 to 5 of the present invention. Detailed Implementation

[0035] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments.

[0036] This invention CuCrNi x The TiZr high-entropy alloy is composed of Cu, Cr, Ni, Ti, and Zr; the atomic ratio of Cu, Cr, Ni, Ti, and Zr is 1:1:x:1:1, where x = 0.1 to 10.

[0037] The purity of Ti, Zr, and Cr is 95%–99.99%, and the purity of Ni and Cu is 99.9%–99.99%.

[0038] This invention CuCrNix The preparation method of TiZr high-entropy alloy is carried out according to the following steps:

[0039] Step 1: Polish the surfaces of Cu, Cr, Ni, Ti, and Zr elements. Ti, Zr, and Cr are made from elemental particles, Ni is made from Ni blocks, and Cu is made from Cu blocks. Remove surface impurities and oxides, and then place them in industrial-grade ethanol for ultrasonic cleaning for 5 to 30 minutes. After drying, weigh the raw materials Cu, Cr, Ni, Ti, and Zr.

[0040] The atomic ratio of Cu, Cr, Ni, Ti, and Zr is 1:1:x:1:1, where x = 0.1 to 10.

[0041] The purity of Ti, Zr, and Cr is 95%–99.99%, and the purity of Ni and Cu is 99.9%–99.99%.

[0042] Step 2: Place the raw materials weighed in Step 1 into the water-cooled copper crucible in the vacuum arc melting furnace in the order of Cu, Ni, Ti, Zr, Cr. Then place a separate pure Ti block in another crucible and close the furnace door.

[0043] Step 3: Turn on the vacuum pump to evacuate until the vacuum level is below 5.5 × 10⁻⁶. -3 MPa, open the charging valve to charge high-purity argon gas into the furnace of the vacuum arc melting furnace to 5×10 MPa. -2 MPa, then evacuate to 5.5 × 10 MPa again. -3 MPa, then refill with high-purity argon gas to 5×10. -2 MPa;

[0044] Step 4: Begin arc ignition and melting. After melting, cool in the furnace to obtain CuCrNi. x TiZr high-entropy alloy ingots;

[0045] The smelting process is as follows: First, pure Ti blocks are smelted to deplete the residual oxygen in the furnace. The smelting current is 200A to 300A and the smelting time is 5 to 15 minutes. Then, Cu, Ni, Ti, Zr, and Cr elements in a water-cooled copper crucible are smelted to obtain a mixed liquid. The smelting current is 280A to 400A. The mixed liquid is smelted repeatedly 3 to 10 times, with each smelting time being 5 to 15 minutes. The sample must be turned over after each smelting.

[0046] Step 5, the CuCrNi obtained in step 4 x TiZr high-entropy alloy ingots were placed in a vacuum tube furnace for homogenization annealing at temperatures ranging from 400℃ to 1200℃ for 2 to 26 hours. After furnace cooling, CuCrNi was obtained. xTiZr high-entropy alloy materials.

[0047] CuCrNi x The microstructure of TiZr high-entropy alloy in the as-cast state mainly consists of FCC and BCC phases. The increased number of alloying elements enhances the high-entropy effect, and the retarded diffusion effect of high-entropy alloys makes atomic diffusion relatively difficult, hindering nucleation and growth during crystallization and reducing the likelihood of coarse grains. The microstructure primarily consists of BCC-structured dendrites and an interdendritic FCC matrix phase. The abundance of slip systems in the FCC structure improves the alloy's ductility and toughness; the fewer slip systems in the single-phase solid solution of the BCC structure, combined with the solid solution strengthening effect of multi-principal element alloys, increases the strength of the high-entropy alloy. With the increase of Ni, CuCrNi... x The enhanced FCC diffraction peaks of TiZr high-entropy alloys and the finer, more uniform dendrites improve their plasticity. By adjusting the Ni content, the properties of CuCrNi alloys can be altered. x The mixing entropy and mixing enthalpy of the TiZr high-entropy alloy are beneficial for controlling the volume ratio of the BCC and FCC phases, achieving a perfect balance between strength and toughness. Simultaneously, during subsequent heat treatment, the precipitation of the Laves phase and some other precipitates at grain boundaries and between FCC dendrites effectively inhibits dislocation movement, causing dislocation pile-up and playing a role in grain boundary strengthening and precipitation strengthening, thereby improving the alloy's strength. The "cocktail effect" of the high-entropy alloy allows each element to exert a combined effect on the alloy's properties, thus enabling the CuCrNi alloy of this invention... x TiZr high-entropy alloys can combine high strength with good plasticity.

[0048] Example 1

[0049] Step 1: Polish the surfaces of Ti, Zr, Cr with a purity of 95% and Cu, Ni with a purity of 99.9%. Ti, Zr, and Cr are made of elemental particles, Ni is made of Ni blocks, and Cu is made of Cu blocks. Remove surface impurities and oxides, and then put them into industrial-grade ethanol for ultrasonic cleaning for 15 minutes. After drying, weigh the raw materials Cu, Cr, Ni, Ti, and Zr.

[0050] The atomic ratio of Cu, Cr, Ni, Ti, and Zr is 1:1:0.1:1:1;

[0051] Step 2: Place the raw materials weighed in Step 1 into the water-cooled copper crucible in the vacuum arc melting furnace in the order of Cu, Ni, Ti, Zr, Cr. Then place a separate pure Ti block in another crucible and close the furnace door.

[0052] Step 3: Turn on the vacuum pump to evacuate until the vacuum level is below 5.5 × 10⁻⁶. -3MPa, open the charging valve to charge high-purity argon gas into the furnace of the vacuum arc melting furnace to 5×10 MPa. -2 MPa, then evacuate to 5.5 × 10 MPa again. -3 MPa, then refill with high-purity argon gas to 5×10. -2 MPa;

[0053] Step 4: Begin arc ignition and melting. After melting, cool in the furnace to obtain CuCrNi. 0.1 TiZr high-entropy alloy ingots;

[0054] The smelting process is as follows: First, pure Ti blocks are smelted to deplete the residual oxygen in the furnace. The smelting current is 200A and the smelting time is 15min. Then, Cu, Ni, Ti, Zr and Cr elements in a water-cooled copper crucible are smelted to obtain a mixed liquid. The smelting current is 280A. The mixed liquid is smelted repeatedly 3 times, with each smelting time being 15min. The sample must be turned over after each smelting.

[0055] Step 5, the CuCrNi obtained in step 4 x TiZr high-entropy alloy ingots were placed in a vacuum tube furnace for homogenization annealing at 1200℃ for 2 hours. After furnace cooling, CuCrNi was obtained. 0.1 TiZr high-entropy alloy materials.

[0056] Example 2

[0057] Step 1: Polish the surfaces of Ti, Zr, Cr with a purity of 99% and Cu, Ni with a purity of 99.9%. Ti, Zr, and Cr are made of elemental particles, Ni is made of Ni blocks, and Cu is made of Cu blocks. Remove surface impurities and oxides, then put them into industrial-grade ethanol for ultrasonic cleaning for 5 minutes, blow dry, and weigh the raw materials Cu, Cr, Ni, Ti, and Zr.

[0058] The atomic ratio of Cu, Cr, Ni, Ti, and Zr is 1:1:0.5:1:1;

[0059] Step 2: Place the raw materials weighed in Step 1 into the water-cooled copper crucible in the vacuum arc melting furnace in the order of Cu, Ni, Ti, Zr, Cr. Then place a separate pure Ti block in another crucible and close the furnace door.

[0060] Step 3: Turn on the vacuum pump to evacuate until the vacuum level is below 5.5 × 10⁻⁶. -3 MPa, open the charging valve to charge high-purity argon gas into the furnace of the vacuum arc melting furnace to 5×10 MPa. -2 MPa, then evacuate to 5.5 × 10 MPa again. -3 MPa, then refill with high-purity argon gas to 5×10. -2MPa;

[0061] Step 4: Begin arc ignition and melting. After melting, cool in the furnace to obtain CuCrNi. 0.5 TiZr high-entropy alloy ingots;

[0062] The smelting process is as follows: First, pure Ti blocks are smelted to deplete the residual oxygen in the furnace. The smelting current is 230A and the smelting time is 12min. Then, Cu, Ni, Ti, Zr and Cr elements in a water-cooled copper crucible are smelted to obtain a mixed liquid. The smelting current is 300A. The mixed liquid is smelted repeatedly 5 times, with each smelting time being 12min. The sample must be turned over after each smelting.

[0063] Step 5, the CuCrNi obtained in step 4 0.5 TiZr high-entropy alloy ingots were placed in a vacuum tube furnace for homogenization annealing at 1000℃ for 20 hours. After furnace cooling, CuCrNi was obtained. 0.5 TiZr high-entropy alloy materials.

[0064] Figure 1 It is the CuCrNi prepared in Example 2 0.5 Microstructure of TiZr high-entropy alloy Figure 2 These are high-magnification scanning electron microscope (SEM) images. Due to the hysteresis diffusion effect of the high-entropy alloy, it is not easy for coarsened grains to form. Its microstructure is mainly composed of dendrites growing in a vertical direction. When the Ni content is low, the high-entropy alloy is mainly composed of face-centered cubic (fcc), body-centered cubic (bcc), and hexagonal close-packed (hcp) structures. The high-entropy alloy prepared in this embodiment has a compressive strength of 632.9 MPa, an elongation of 5.8%, and a microhardness of 707.3 HV, exhibiting high strength and hardness.

[0065] Example 3

[0066] Step 1: Polish the surfaces of Ti, Zr, Cr with a purity of 99.5% and Cu, Ni with a purity of 99.95%. Ti, Zr, and Cr are made of elemental particles, Ni is made of Ni blocks, and Cu is made of Cu blocks. Remove surface impurities and oxides, then put them into industrial-grade ethanol for ultrasonic cleaning for 20 minutes, blow dry, and weigh the raw materials Cu, Cr, Ni, Ti, and Zr.

[0067] The atomic ratio of Cu, Cr, Ni, Ti, and Zr is 1:1:1:1:1;

[0068] Step 2: Place the raw materials weighed in Step 1 into the water-cooled copper crucible in the vacuum arc melting furnace in the order of Cu, Ni, Ti, Zr, Cr. Then place a separate pure Ti block in another crucible and close the furnace door.

[0069] Step 3: Turn on the vacuum pump to evacuate until the vacuum level is below 5.5 × 10⁻⁶. -3 MPa, open the charging valve to charge high-purity argon gas into the furnace of the vacuum arc melting furnace to 5×10 MPa. -2 MPa, then evacuate to 5.5 × 10 MPa again. -3 MPa, then refill with high-purity argon gas to 5×10. -2 MPa;

[0070] Step 4: Start arc ignition and melting, and cool with the furnace after melting to obtain CuCrNi1TiZr high-entropy alloy ingot;

[0071] The smelting process is as follows: First, pure Ti blocks are smelted to deplete the residual oxygen in the furnace. The smelting current is 260A and the smelting time is 10min. Then, Cu, Ni, Ti, Zr and Cr elements in a water-cooled copper crucible are smelted to obtain a mixed liquid. The smelting current is 320A. The mixed liquid is smelted repeatedly 6 times, with each smelting time being 10min. The sample must be turned over after each smelting.

[0072] Step 5: Place the CuCrNi1TiZr high-entropy alloy ingot obtained in Step 4 into a vacuum tube furnace for homogenization annealing treatment at a temperature of 900℃ for 15 hours. After furnace cooling, the CuCrNi1TiZr high-entropy alloy material is obtained.

[0073] Figure 3 This is a microstructure diagram of the CuCrNi1TiZr high-entropy alloy prepared in Example 3. Figure 4 The image is a high-magnification scanning electron microscope image. Due to the hysteresis diffusion effect of the high-entropy alloy, the alloy is not prone to producing coarsened grains. Its microstructure is mainly composed of dendrites that grow in a vertical direction. The high-entropy alloy prepared in this embodiment has a compressive strength of 718.6 MPa, an elongation of 11.7%, and a microhardness of 692.8 HV. It has high strength and hardness and good plasticity at room temperature.

[0074] Example 4

[0075] Step 1: Polish the surface of Ti, Zr, Cr, Cu and Ni elements with a purity of 99.97%. Ti, Zr and Cr are made of elemental particles, Ni is made of Ni blocks and Cu is made of Cu blocks. Remove surface impurities and oxides, then put them into industrial grade ethanol for ultrasonic cleaning for 27 minutes, blow dry, and weigh the raw materials Cu, Cr, Ni, Ti and Zr.

[0076] The atomic ratio of Cu, Cr, Ni, Ti, and Zr is 1:1:1.5:1:1;

[0077] Step 2: Place the raw materials weighed in Step 1 into the water-cooled copper crucible in the vacuum arc melting furnace in the order of Cu, Ni, Ti, Zr, Cr. Then place a separate pure Ti block in another crucible and close the furnace door.

[0078] Step 3: Turn on the vacuum pump to evacuate until the vacuum level is below 5.5 × 10⁻⁶. -3 MPa, open the charging valve to charge high-purity argon gas into the furnace of the vacuum arc melting furnace to 5×10 MPa. -2 MPa, then evacuate to 5.5 × 10 MPa again. -3 MPa, then refill with high-purity argon gas to 5×10. -2 MPa;

[0079] Step 4: Begin arc ignition and melting. After melting, cool in the furnace to obtain CuCrNi. 1.5 TiZr high-entropy alloy ingots;

[0080] The smelting process is as follows: First, pure Ti blocks are smelted to deplete the residual oxygen in the furnace. The smelting current is 290A and the smelting time is 8 minutes. Then, Cu, Ni, Ti, Zr and Cr elements in a water-cooled copper crucible are smelted to obtain a mixed liquid. The smelting current is 340A. The mixed liquid is smelted repeatedly 6 times, with each smelting time being 8 minutes. The sample must be turned over after each smelting.

[0081] Step 5, the CuCrNi obtained in step 4 1.5 TiZr high-entropy alloy ingots were placed in a vacuum tube furnace for homogenization annealing at 800℃ for 25 hours. After furnace cooling, CuCrNi was obtained. 1.5 TiZr high-entropy alloy materials.

[0082] Figure 5 CuCrNi prepared in Example 4 1.5 Microstructure of TiZr high-entropy alloy Figure 6 The image is a high-magnification scanning electron microscope image. Due to the hysteresis diffusion effect of the high-entropy alloy, the alloy is not prone to producing coarsened grains. Its microstructure is mainly composed of dendrites that grow in a vertical direction. The high-entropy alloy prepared in this embodiment has a compressive strength of 947.1 MPa, an elongation of 10.1%, and a microhardness of 561.4 HV. It has high strength and hardness and good plasticity at room temperature.

[0083] Example 5

[0084] Step 1: Polish the surface of Ti, Zr, Cr, Cu and Ni elements with a purity of 99.99%. Ti, Zr and Cr are made of elemental particles, Ni is made of Ni blocks and Cu is made of Cu blocks. Remove surface impurities and oxides, then put them into industrial grade ethanol for ultrasonic cleaning for 30 minutes, blow dry, and weigh the raw materials Cu, Cr, Ni, Ti and Zr.

[0085] The atomic ratio of Cu, Cr, Ni, Ti, and Zr is 1:1:2:1:1;

[0086] Step 2: Place the raw materials weighed in Step 1 into the water-cooled copper crucible in the vacuum arc melting furnace in the order of Cu, Ni, Ti, Zr, Cr. Then place a separate pure Ti block in another crucible and close the furnace door.

[0087] Step 3: Turn on the vacuum pump to evacuate until the vacuum level is below 5.5 × 10⁻⁶. -3 MPa, open the charging valve to charge high-purity argon gas into the furnace of the vacuum arc melting furnace to 5×10 MPa. -2 MPa, then evacuate to 5.5 × 10 MPa again. -3 MPa, then refill with high-purity argon gas to 5×10. -2 MPa;

[0088] Step 4: Start arc ignition and melting, and cool with the furnace after melting to obtain CuCrNi2TiZr high-entropy alloy ingot;

[0089] The smelting process is as follows: First, pure Ti blocks are smelted to deplete the residual oxygen in the furnace. The smelting current is 300A and the smelting time is 8 minutes. Then, Cu, Ni, Ti, Zr and Cr elements in a water-cooled copper crucible are smelted to obtain a mixed liquid. The smelting current is 360A. The mixed liquid is smelted repeatedly 7 times, with each smelting time being 8 minutes. The sample must be turned over after each smelting.

[0090] Step 5: Place the CuCrNi2TiZr high-entropy alloy ingot obtained in Step 4 into a vacuum tube furnace for homogenization annealing treatment at a temperature of 700℃ for 26 hours. After furnace cooling, the CuCrNi2TiZr high-entropy alloy material is obtained.

[0091] Figure 7 The image shows the microstructure of the CuCrNi2TiZr high-entropy alloy prepared in Example 5. Figure 8These are high-magnification scanning electron microscope images. Due to the hysteresis diffusion effect of the high-entropy alloy, the alloy is not prone to producing coarsened grains, and its microstructure is mainly composed of dendrites that grow in a vertical direction. The high-entropy alloy prepared in this embodiment has a compressive strength of 1047.5 MPa, an elongation of 16.6%, and a microhardness of 544.8 HV, exhibiting high strength and hardness, and good plasticity at room temperature.

[0092] Example 6

[0093] Step 1: Polish the surface of Ti, Zr, Cr, Cu and Ni elements with a purity of 99.99%. Ti, Zr and Cr are made of elemental particles, Ni is made of Ni blocks and Cu is made of Cu blocks. Remove surface impurities and oxides, then put them into industrial grade ethanol for ultrasonic cleaning for 30 minutes, blow dry, and weigh the raw materials Cu, Cr, Ni, Ti and Zr.

[0094] The atomic ratio of Cu, Cr, Ni, Ti, and Zr is 1:1:10:1:1;

[0095] Step 2: Place the raw materials weighed in Step 1 into the water-cooled copper crucible in the vacuum arc melting furnace in the order of Cu, Ni, Ti, Zr, Cr. Then place a separate pure Ti block in another crucible and close the furnace door.

[0096] Step 3: Turn on the vacuum pump to evacuate until the vacuum level is below 5.5 × 10⁻⁶. -3 MPa, open the charging valve to charge high-purity argon gas into the furnace of the vacuum arc melting furnace to 5×10 MPa. -2 MPa, then evacuate to 5.5 × 10 MPa again. -3 MPa, then refill with high-purity argon gas to 5×10. -2 MPa;

[0097] Step 4: Begin arc ignition and melting. After melting, cool in the furnace to obtain CuCrNi. 10 TiZr high-entropy alloy ingots;

[0098] The smelting process is as follows: First, pure Ti blocks are smelted to deplete the residual oxygen in the furnace. The smelting current is 300A and the smelting time is 5min. Then, Cu, Ni, Ti, Zr and Cr elements in a water-cooled copper crucible are smelted to obtain a mixed liquid. The smelting current is 400A. The mixed liquid is smelted repeatedly 10 times, with each smelting time being 5min. The sample must be turned over after each smelting.

[0099] Step 5, the CuCrNi obtained in step 4 10 TiZr high-entropy alloy ingots were placed in a vacuum tube furnace for homogenization annealing at 400℃ for 26 hours. After furnace cooling, CuCrNi was obtained.10 TiZr high-entropy alloy materials.

[0100] Figure 9 The XRD patterns of the high-entropy alloys prepared in Examples 2 and 5 are shown. Figure 10 The figures show the compressive stress-strain curves of the high-entropy alloys prepared in Examples 2-5. (The last sentence appears to be incomplete and possibly refers to a different context.) x When the Ni content is low, the TiZr high-entropy alloy consists of FCC, BCC, and HCP structures. As the Ni content increases, the structure of the high-entropy alloy gradually transforms into FCC+BCC. With the increase of Ni content, the compressive strength and elongation of the high-entropy alloy both increase.

Claims

1. A method for preparing CuCrNixTiZr high-entropy alloy, characterized in that, The method is implemented according to the following steps: Step 1, cleaning Cu, Cr, Ni, Ti, Zr elements, weighing Cu, Cr, Ni, Ti, Zr elements, the atomic ratio of Cu, Cr, Ni, Ti, Zr is 1:1:x:1:1, wherein x = 0.1-10; Step 2, putting the weighed raw materials in step 1 into a water-cooled copper crucible in a vacuum arc melting furnace in the order of Cu, Ni, Ti, Zr, Cr, and then putting a pure Ti block into another crucible, and closing the furnace door; Step 3, open the vacuum pump to vacuum until the vacuum degree is lower than 5.5 x 10 -3 MPa, open the gas filling valve to fill high-purity argon into the hearth of the vacuum arc melting furnace to 5 x 10 -2 MPa, vacuum again to 5.5 x 10 -3 MPa, fill high-purity argon again to 5 x 10 -2 MPa; Step 4, starting arc melting, and cooling in the furnace after melting to obtain a CuCrNixTiZr high-entropy alloy ingot; In step 4, the melting process is as follows: first, melting the Ti element to consume the residual oxygen in the furnace, wherein the melting current is 200A-300A, and the melting time is 5min-15min; then, melting the Cu, Ni, Ti, Zr, Cr elements in the water-cooled copper crucible to obtain a mixed liquid, wherein the melting current is 280A-400A, the mixed liquid is repeatedly melted for 3-10 times, the melting time is 5min-15min each time, and the sample is turned over after each melting; Step 5, putting the CuCrNixTiZr high-entropy alloy ingot obtained in step 4 into a vacuum tube furnace for homogenization annealing treatment, and cooling in the furnace to obtain a CuCrNixTiZr high-entropy alloy material; The CuCrNixTiZr high-entropy alloy material is composed of FCC phase and BCC phase structures; In step 5, the homogenization annealing temperature is 400℃-1200℃, and the holding time is 2h-26h.

2. The method for preparing the CuCrNixTiZr high-entropy alloy according to claim 1, characterized in that, In step 1, the cleaning process is as follows: polishing the surface of Cu, Cr, Ni, Ti, Zr elements to remove surface impurities and oxides, and then putting them into industrial-grade ethanol for ultrasonic cleaning for 5min-30min, and then blowing dry.

3. The method for preparing the CuCrNixTiZr high-entropy alloy according to claim 1, characterized in that, The purity of Ti, Zr, Cr is 95%-99.99%, and the purity of Ni, Cu is 99.9%-99.99%.

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