Lightweight refractory multi-component alloy material with high processing forming capacity and preparation method of lightweight refractory multi-component alloy material

Abstract

The invention belongs to the technical field of light refractory multi-component alloy materials, and particularly relates to a light refractory multi-component alloy material with high machining forming capacity and a preparation method of the light refractory multi-component alloy material. % of V: 8.9 to 11.5 at. % of Zr: 13.2 to 17 at. % of Nb: 8.9 to 11.5 at. % of Al, and the grain size of the alloy material is 39.3 to 62.1 [mu] m. The alloy disclosed by the invention is uniform in structure, is of a single centered cubic structure, is low in density and excellent in comprehensive mechanical property and has excellent processability, and when the rolling pressing rate is 90%, the elongation reaches 409%. According to the preparation method, cold rolling and recrystallization heat treatment are added, the grain size is refined, the smaller the grain size is within the micron-level range, the better the mechanical property is, hardness can be improved, and strength and plasticity are further improved.

Description

Technical Field

[0001] The present invention belongs to the technical field of lightweight refractory multi-component alloy materials, and in particular relates to a lightweight refractory multi-component alloy material with high processing and forming capability and a preparation method thereof. Background Art

[0002] In order to meet the growing challenges brought by the environmental and energy crises, the development of innovative lightweight materials has become a key research area across various fields, including energy, transportation, military and aerospace industries. Traditional lightweight alloys are usually based on one or two dominant elements, such as titanium alloys, magnesium alloys, aluminum alloys, etc., and their mechanical properties are changed or optimized by adding small amounts of other elements.

[0003] In the past decade, the emergence of high entropy alloys has provided a new direction for the design of high-performance metal materials. It was originally defined as an alloy composed of 5 or more elements, usually with equimolar or nearly equimolar composition, and each main component ranges from 5% to 35%. With the deepening of research, a new way has emerged, which is to use mixed entropy to define high entropy and medium entropy alloys. In some high entropy alloys under the traditional definition, one component is the main component, and the remaining four components also exceed the minimum content, but according to the definition of mixed entropy, it belongs to a medium entropy alloy. Whether it is a high entropy alloy or a medium entropy alloy, it can be called a multi-component alloy. In order to reduce controversy, the high / medium entropy alloy material of the present invention is called a multi-component alloy material.

[0004] Refractory multi-component alloys composed of refractory metal elements have attracted widespread attention due to their excellent mechanical properties at high temperatures. However, refractory multi-component alloys face challenges, including high brittleness and high density, which is particularly worrying in the aerospace field. In addition, the raw material prices of refractory metal elements V, Zr, and Nb are relatively expensive compared to Ti. The addition of too many refractory metal elements not only increases the cost, but also increases the material preparation and processing costs. The low cost-effectiveness and limited processing capabilities further hinder its practical application. Developing materials with excellent comprehensive mechanical properties and reducing production costs has always been the pursuit of metallurgical workers. Summary of the invention

[0005] One of the purposes of the present invention is to provide a lightweight refractory multi-component alloy material with high processing and forming capability, which has uniform alloy structure, low density, excellent comprehensive mechanical properties and excellent processing performance.

[0006] The second object of the present invention is to provide a method for preparing a lightweight refractory multi-component alloy material with high processing and forming ability, the preparation process is simple and easy to adjust.

[0007] The solution adopted by the present invention to achieve one of the purposes is: a lightweight refractory multi-component alloy material with high processing and forming ability, which includes the following components in atomic percentage: Ti: 60at.%; V: 8.9-11.5at.%; Zr: 13.2-17at.%; Nb: 8.9-11.5at.%; Al: 0-9at.%, and the grain size of the alloy material is 39.3-62.1μm.

[0008] The present invention adjusts the content of elements through component design, reduces the amount of metal elements with high cost, high density and high melting point, reduces raw material cost, preparation cost and density, and increases tensile yield strength and room temperature tensile plasticity.

[0009] Preferably, the following components are included in atomic percentage: Ti: 60 at. %; V: 8.9-10.6 at. %; Zr: 13.2-15.8 at. %; Nb: 8.9-10.6 at. %; Al: 3-9 at. %.

[0010] Preferably, the atomic percentages of V, Zr and Nb are 0.9-1.1:1.4-1.6:0.9-1.1.

[0011] Preferably, the density of the alloy material is 5.11-5.50 g / cm 3 , the tensile yield strength is 638.3-853.4MPa, and the room temperature tensile plasticity is 24.3%-33.5%.

[0012] Preferably, the alloy material is a single body-centered cubic structure.

[0013] The solution adopted by the present invention to achieve the second purpose is: a method for preparing the lightweight refractory multi-component alloy material with high processing and forming ability, comprising the following steps:

[0014] (1) Remove impurities and oxide scale from the surface of the raw material block and clean it, and weigh the required raw material mass;

[0015] (2) Melting the raw materials;

[0016] (3) The smelted material is subjected to homogenization heat treatment and then cooled;

[0017] (4) cold rolling the cooled material;

[0018] (5) The cold-rolled material is subjected to recrystallization heat treatment, and the alloy material is obtained after cooling.

[0019] In the preparation method of the present invention, the two processes of rolling and recrystallization annealing can greatly refine the grains (originally more than one hundred microns in size). The grain size is related to the mechanical properties. The finer the grains, the better the strength and plasticity.

[0020] Preferably, in step (2), an arc melting furnace is used for melting, and the vacuum degree is drawn to 5×10 3 Pa, then fill with high-purity argon gas to a pressure of 0.02 to 0.05 MPa, and then evacuate to a vacuum of 5×10 3 Pa, repeat several times, fill with high-purity argon gas to the pressure of 0.02 to 0.05MPa and start smelting. The current during smelting is 200-300A; turn over after each smelting, and repeat the smelting for at least 10 times.

[0021] Preferably, in step (3), the smelted material is vacuum sealed and then heat treated at a temperature of 990-1010° C. for 1-3 hours, followed by water quenching.

[0022] Preferably, in step (4), the rolling pressure is 80%-90%, and multiple passes are used, with each pass pressing 0.1-0.3 mm.

[0023] Preferably, in step (5), the temperature of the recrystallization heat treatment is 740-760° C., the time is 25-35 min, and the water quenching is performed.

[0024] The alloy material of the present invention forms a single body-centered cubic structure by combining Al with other metal elements, and since Al and Zr have the most negative mixing enthalpy, a local chemical ordered structure is formed at the nanoscale. The local chemical order can improve the strength and plasticity of the material by affecting dislocation movement.

[0025] The present invention has the following advantages and beneficial effects:

[0026] In response to the challenges of current refractory multi-component alloys such as high density, poor room temperature plasticity and high cost, the present invention proposes a lightweight refractory multi-component alloy material with high processing and forming capability. The alloy has uniform microstructure, a single body-centered cubic structure, low density, excellent comprehensive mechanical properties and excellent processing performance. When the rolling reduction rate is 90%, the elongation reaches 409%.

[0027] The alloy material of the present invention has Ti as the main component, and the content of 60 at.% is kept unchanged, the content of Al light / cheap elements is increased, and the content of V, Zr and Nb heavy / expensive elements is reduced, which reduces the cost of raw materials while reducing the density, but improves the strength and plasticity. The theoretical density is 5.11-5.50g / cm 3, the tensile yield strength is 638.3-853.4MPa, and the room temperature tensile plasticity is 24.3-33.5%, which can meet the growing challenges brought by the environmental and energy crises.

[0028] The invention provides a material with light weight, high processing and forming capability and excellent comprehensive mechanical properties for the energy, transportation, military and aerospace industries.

[0029] The preparation method of the present invention refines the grain size by adding cold rolling and recrystallization heat treatment. The smaller the grain size is within the micrometer range, the better the mechanical properties are, and the hardness can be improved, further improving the strength and plasticity at the same time. Through the recrystallization of the alloy structure, the number of large-sized grains and columnar grains can be reduced, and the uniformity of strain when the material is subjected to force in all directions can be promoted, so that the prepared alloy material. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 XRD diffraction analysis diagram of the recrystallized light-weight refractory multi-component alloy with high processing and forming capability according to Example 1-4;

[0031] Figure 2 The tensile engineering stress-strain curve of the recrystallized light-weight refractory multi-component alloy with high processing and forming ability measured at room temperature in Example 1-4;

[0032] Figure 3 The hardness diagrams of the lightweight refractory multi-component alloys with high processing and forming ability in Examples 1-4 were measured in the homogenized state, the rolled state and the recrystallized state respectively;

[0033] Figure 4 The recrystallized Ti in Example 1 60 V 11.5 Zr 17 Nb 11.5 Microscopic morphology of lightweight refractory multi-component alloy with high processing and forming capability;

[0034] Figure 5 The recrystallized Ti in Example 1 60 V 11.5 Zr 17 Nb 11.5 Electron backscatter diffraction pattern of lightweight refractory multi-component alloy with high processing and forming capability;

[0035] Figure 6 The recrystallized Ti in Example 1 60 V 11.5 Zr 17 Nb 11.5 High-resolution transmission electron microscope images of lightweight refractory multi-component alloys with high processing and forming capabilities;

[0036] Figure 7Example 2 is the homogenized Ti 60 V 10.6 Zr 15.8 Nb 10.6 Al 3 Microscopic morphology of lightweight refractory multi-component alloy with high processing and forming capability;

[0037] Figure 8 The recrystallized Ti in Example 2 60 V 10.6 Zr 15.8 Nb 10.6 Al 3 Microscopic morphology of lightweight refractory multi-component alloy with high processing and forming capability;

[0038] Fig. 9 The recrystallized Ti in Example 2 60 V 10.6 Zr 15.8 Nb 10.6 Al 3 Electron backscatter diffraction pattern of lightweight refractory multi-component alloy with high processing and forming capability;

[0039] Fig.10 For the recrystallized Ti in Example 3 60 V 9.7 Zr 14.6 Nb 9.7 Al 6 Microscopic morphology of lightweight refractory multi-component alloy with high processing and forming capability;

[0040] Fig.11 For the recrystallized Ti in Example 3 60 V 9.7 Zr 14.6 Nb 9.7 Al 6 Electron backscatter diffraction pattern of lightweight refractory multi-component alloy with high processing and forming capability;

[0041] Fig.12 For the recrystallized Ti in Example 3 60 V 9.7 Zr 14.6 Nb 9.7 Al 6 High-resolution transmission electron microscope images of lightweight refractory multi-component alloys with high processing and forming capabilities;

[0042] Fig.13 For the recrystallized Ti in Example 3 60 V 9.7 Zr 14.6 Nb 9.7 Al 6 Transmission electron microscope inverse Fourier transform image of lightweight refractory multi-component alloy with high processing and forming capability;

[0043] Fig.14 Example 4 is the homogenized Ti 60 V 8.9 Zr 13.2 Nb 8.9 Al 9 Microscopic morphology of lightweight refractory multi-component alloy with high processing and forming capability;

[0044] Fig.15 The recrystallized Ti in Example 4 60 V 8.9 Zr 13.2 Nb 8.9 Al 9 Microscopic morphology of lightweight refractory multi-component alloy with high processing and forming capability;

[0045] Fig.16 The recrystallized Ti in Example 4 60 V 8.9 Zr 13.2 Nb 8.9 Al 9 Electron backscatter diffraction pattern of lightweight refractory multi-component alloy with high processing and forming capability;

[0046] Fig.17 This is a processing diagram of the lightweight refractory multi-component alloy material with high processing and forming ability of Example 1-4, in which the rolling reduction amount is 80%;

[0047] Fig.18 Example 3 is a lightweight refractory multi-component alloy Ti with high processing and forming ability 60 V 9.7 Zr 14.6 Nb 9.7 Al 6 Processing diagram for different rolling reduction amounts. DETAILED DESCRIPTION

[0048] In order to better understand the technical solution of the present invention, the content of the present invention includes but is not limited to the specific implementation methods below, and similar technologies and methods should be considered within the scope of protection of the present invention. In order to make the technical problems, technical solutions and advantages to be solved by the present invention clearer, the following will be described in detail with reference to the accompanying drawings and specific embodiments.

[0049] It should be clear that the embodiments described in the present invention are only part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0050] The terms used in the embodiments of the present invention are only for the purpose of describing specific embodiments, and are not intended to limit the present invention. The singular forms "a", "said" and "the" used in the embodiments of the present invention and the appended claims are also intended to include plural forms, unless the context clearly indicates other meanings.

[0051] A light and refractory multi-component alloy material with high processing and forming ability, wherein the light and refractory multi-component alloy material with high processing and forming ability has the following atomic ratios: Ti: 60 at.%, V: 8.9-11.5 at.%, Zr: 13.2-17 at.%, Nb: 8.9-11.5 at.%, and Al: 0-9 at.%.

[0052] Specifically, the high processing and forming ability lightweight refractory multi-component alloy includes the following components in atomic percentage: Ti: 60at.%; V: 8.9-11.5at.% (for example, 8.9at.%, 9.7at.%, 10.6at.%, 11.5at.%, etc.); Zr: 13.2-17at.% (for example, 13.2at.%, 14.6at.%, 15.8at.%, 17at.%, etc.); Nb: 8.9-11.5at.% (for example, 8.9at.%, 9.7at.%, 10.6at.%, 11.5at.%, etc.); Al: 0-9at.% (for example, 0at.%, 3at.%, 6at.%, 9at.%, etc.)

[0053] Preparation steps of a lightweight refractory multi-component alloy with high processing and forming capability:

[0054] (1) Remove impurities and oxide scale from the surface of the raw material block and clean it, then accurately weigh the required mass of the raw material;

[0055] (2) Use an arc melting furnace for melting. Before melting, the vacuum degree should be reduced to 5×10 3 Pa, then fill with high-purity argon gas to a pressure of 0.02 to 0.05 MPa, and then evacuate to a vacuum of 5×10 3 Pa, it is considered as one purge. After three purges, high-purity argon is filled to a pressure of 0.02 to 0.05 MPa to start smelting. The current during smelting is 200-300A; each time the smelting is completed, it needs to be turned over, and the smelting must be repeated at least 10 times;

[0056] (3) After homogenization heat treatment, the ingot is placed in a quartz glass tube and the vacuum degree of the glass tube is evacuated to 2×10 3 Pa, use hydrogen flame to seal the tube, and then perform heat treatment. The specific process is: temperature 990℃-1010℃, time 1-3 hours, water quenching cooling;

[0057] (4) cold rolling with a rolling reduction of 80% and multiple passes with a reduction of 0.1-0.3 mm per pass;

[0058] (5) Finally, recrystallization heat treatment is performed, and the specific process is: temperature 740℃-760℃, time 25-35min, and water quenching cooling.

[0059] Example 1

[0060] This embodiment provides a lightweight, high-strength, high-entropy alloy containing Ti, V, Zr, and Nb elements, the chemical formula of which is Ti 60 V 11.5 Zr 17 Nb 11.5 , its theoretical density is 5.50g / cm 3 The specific preparation method is as follows:

[0061] Step 1, raw material selection and batching: Select short rod-shaped Ti particles with a purity of 99.9%, short rod-shaped V particles with a purity of 99.9%, short rod-shaped Zr particles with a purity of 99.9%, and short rod-shaped Nb particles with a purity of 99.9%. The selected high-purity Ti, V, Zr, and Nb metal single substances are polished with 240-mesh coarse sandpaper to remove the oxide skin on the surface of the single substance. The raw materials are cleaned by ultrasonic oscillation of anhydrous ethanol solution and set aside. Based on the total mass of 40g of each element raw material, the weighed masses of the metal particle raw materials Ti, V, Zr, and Nb are 18.907g (47.26wt.%), 3.855g (9.64wt.%), 10.206g (25.52wt.%), and 7.032g (17.58wt.%), respectively, with an error value of ±0.001g.

[0062] Step 2: Melting: Place the raw materials prepared in step 1 into an arc melting furnace for melting. Before melting, draw the vacuum degree to 5×10 3 Pa, then fill with high-purity argon gas to a pressure of 0.02 to 0.05 MPa, and then evacuate to a vacuum of 5×10 3 Pa is considered as one purge. After three purges, high-purity argon is filled to a pressure of 0.02 to 0.05 MPa to start smelting. The current during smelting is 200-300A. After each smelting, the ingot needs to be turned over, and the smelting is repeated at least 10 times to obtain an ingot.

[0063] Step 3: Homogenization heat treatment: Place the ingot into a quartz glass tube and evacuate the glass tube to a vacuum degree of 2×10 3 Pa, use hydrogen flame to seal the tube, and then perform homogenization heat treatment. The specific process is: temperature 990℃-1010℃, time 2 hours, water quenching cooling.

[0064] Step 4: Use 240-mesh and 600-mesh coarse sandpaper to grind the surface of the sample after the homogenization heat treatment in step 3 to remove the oxide scale. Then cold rolling is performed, with a rolling pressure of 80%, multiple passes, and each pass has a pressure of 0.1-0.3 mm.

[0065] Step 5: Pre-cut the sample cold-rolled in step 4 to the required size, polish it with 240-mesh and 600-mesh coarse sandpaper to remove the oxide scale, put the polished sample into a quartz glass tube, and draw the vacuum degree of the glass tube to 2×10 3 Pa, use hydrogen flame to seal the tube, and then perform recrystallization heat treatment. The specific process is: temperature 740℃-760℃, time 30min, water quenching cooling.

[0066] Figure 1 The recrystallized Ti in Example 1 60 V 11.5 Zr 17 Nb 11.5 The XRD diffraction analysis diagram of the lightweight refractory multi-component alloy with high processing and forming ability proves that the alloy exhibits a single body-centered cubic structure in the recrystallized state. Figure 2 The recrystallized Ti in Example 1 60 V 11.5 Zr 17 Nb 11.5 The tensile engineering stress-strain curve of the lightweight refractory multi-component alloy with high processing and forming ability measured at room temperature shows that the tensile yield strength of Example 1 is 650.0 MPa and the tensile plasticity is 28.5%. Figure 3 The hardness diagrams of Example 1 are measured in the homogenized state, rolled state and recrystallized state respectively. Figure 3 It can be seen that after the rolling process, the hardness of the material increases. At this time, due to the extremely large internal stress caused by plastic processing, recrystallization annealing is required to eliminate the internal stress. Because the regrown grains are finer than the homogenized state, the hardness of the recrystallized state is higher than that of the homogenized state. Figure 4 The recrystallized Ti in Example 1 60 V 11.5 Zr 17 Nb 11.5 Microstructure of the lightweight refractory multi-component alloy with high processing and forming capability. In Example 1, no precipitation phase was found at the grain boundary. Figure 5 The recrystallized Ti in Example 1 60 V 11.5 Zr 17 Nb 11.5 The electron backscattered diffraction pattern of the lightweight refractory multi-component alloy with high processing and forming ability shows that the average grain size is 40.5μm. Figure 6 The recrystallized Ti in Example 1 60 V 11.5Zr 17 Nb 11.5 High-resolution transmission electron microscopy image of a lightweight refractory multi-component alloy with high processing and forming capability. The thumbnail is a Fourier transformed lattice. It can be seen that Example 1 is a single body-centered cubic structure, but no diffuse scattering disk appears and no local chemically ordered structure is observed. Fig.17 This is a processing diagram of a lightweight refractory multi-component alloy material with high processing and forming ability, with a rolling pressure of 80%. From top to bottom, the workpiece is the rolling result of Example 1. Fig.17 It can be seen that after 80% rolling, the workpiece has a full contour, a complete surface with few defects, and has excellent ductility and processing capabilities. It can facilitate metal plastic processing (such as forging and extrusion) into the desired shape, thereby improving material utilization.

[0067] Example 2

[0068] This embodiment provides a lightweight, high-strength, high-entropy alloy containing Ti, V, Zr, Nb, and Al elements, the chemical formula of which is Ti 60 V 10.6 Zr 15.8 Nb 10.6 Al 3 , its theoretical density is 5.37g / cm 3 The specific preparation method is as follows:

[0069] Step 1, raw material selection and batching: Select short rod-shaped Ti particles with a purity of 99.9%, short rod-shaped V particles with a purity of 99.9%, short rod-shaped Zr particles with a purity of 99.9%, short rod-shaped Nb particles with a purity of 99.9%, and short rod-shaped Al particles with a purity of 99.9%. Select high-purity Ti, V, Zr, Nb, and Al metal single substances, and use 240-mesh coarse sandpaper to grind the particle surface to remove the oxide skin on the surface of the single substance. Use anhydrous ethanol solution ultrasonic oscillation to clean the raw materials and set them aside. Based on the total mass of 40g of each element's raw materials, the weighed masses of the metal particle raw materials Ti, V, Zr, Nb and Al are 19.411g (48.53wt.%), 3.649g (9.12wt.%), 9.739g (24.35wt.%), 6.654g (16.63wt.%) and 0.547g (1.37wt.%), respectively, with an error value of ±0.001g. In addition, due to the low melting point of Al and its boiling point close to the melting point of Nb, 0.027g (5%) of Al element is weighed more.

[0070] Step 2: Melting: Place the raw materials prepared in step 1 into an arc melting furnace for melting. Before melting, draw the vacuum degree to 5×10 3 Pa, then fill with high-purity argon gas to a pressure of 0.02 to 0.05 MPa, and then evacuate to a vacuum of 5×10 3Pa is considered as one purge. After three purges, high-purity argon is filled to a pressure of 0.02 to 0.05 MPa to start smelting. The current during smelting is 200-300A. After each smelting, the ingot needs to be turned over, and the smelting is repeated at least 10 times to obtain an ingot.

[0071] Step 3: Homogenization heat treatment: Place the ingot into a quartz glass tube and evacuate the glass tube to a vacuum degree of 2×10 3 Pa, use hydrogen flame to seal the tube, and then perform homogenization heat treatment. The specific process is: temperature 990℃-1010℃, time 2 hours, water quenching cooling.

[0072] Step 4: Use 240-mesh and 600-mesh coarse sandpaper to grind the surface of the sample after the homogenization heat treatment in step 3 to remove the oxide scale. Then cold rolling is performed, with a rolling pressure of 80%, multiple passes, and each pass has a pressure of 0.1-0.3 mm.

[0073] Step 5: Pre-cut the sample cold-rolled in step 4 to the required size, polish it with 240-mesh and 600-mesh coarse sandpaper to remove the oxide scale, put the polished sample into a quartz glass tube, and draw the vacuum degree of the glass tube to 2×10 3 Pa, use hydrogen flame to seal the tube, and then perform recrystallization heat treatment. The specific process is: temperature 740℃-760℃, time 30min, water quenching cooling.

[0074] Figure 1 The recrystallized Ti in Example 2 60 V 10.6 Zr 15.8 Nb 10.6 Al 3 The XRD diffraction analysis diagram of the lightweight refractory multi-component alloy with high processing and forming ability proves that the alloy exhibits a single body-centered cubic structure in the recrystallized state. Figure 2 The recrystallized Ti in Example 2 60 V 10.6 Zr 15.8 Nb 10.6 Al 3 The tensile engineering stress-strain curve of the lightweight refractory multi-component alloy with high processing and forming ability measured at room temperature shows that the tensile yield strength of Example 2 is 714.1 MPa and the tensile plasticity is 32.4%. Figure 3 The hardness diagrams of Example 2 are measured in the homogenized state, rolled state and recrystallized state respectively. Figure 3 It can be seen that after the rolling process, the hardness of the material increases. At this time, due to the extremely large internal stress caused by plastic processing, recrystallization annealing is required to eliminate the internal stress. Because the regrown grains are finer than the homogenized state, the hardness of the recrystallized state is higher than that of the homogenized state. Figure 7Example 2 is the homogenized Ti 60 V 10.6 Zr 15.8 Nb 10.6 Al 3 Microstructure of a lightweight refractory multi-component alloy with high processing capability, where the grains are very coarse. Figure 8 The recrystallized Ti in Example 2 60 V 10.6 Zr 15.8 Nb 10.6 Al 3 Microstructure picture of lightweight refractory multi-component alloy with high processing and forming capability. No precipitation phase was found at the grain boundary in Example 2. Fig. 9 The recrystallized Ti in Example 2 60 V 10.6 Zr 15.8 Nb 10.6 Al 3 The electron backscattered diffraction pattern of the lightweight refractory multi-component alloy with high processing and forming capability shows that the average grain size is 39.3μm and the grain structure is fully refined. Fig.17 This is a processing diagram of a lightweight refractory multi-component alloy material with high processing and forming ability, with a rolling pressure of 80%. The two workpieces from top to bottom are the rolling results of Example 2. Fig.17 It can be seen that after 80% rolling, the workpiece has a full contour, a complete surface with few defects, and has excellent ductility and processing capabilities. It can facilitate metal plastic processing (such as forging and extrusion) into the desired shape, thereby improving material utilization.

[0075] Example 3

[0076] This embodiment provides a lightweight, high-strength, high-entropy alloy containing Ti, V, Zr, Nb, and Al elements, the chemical formula of which is Ti 60 V 9.7 Zr 14.6 Nb 9.7 Al 6 , its theoretical density is 5.24g / cm 3 The specific preparation method is as follows:

[0077] Step 1, raw material selection and batching: Select short rod-shaped Ti particles with a purity of 99.9%, short rod-shaped V particles with a purity of 99.9%, short rod-shaped Zr particles with a purity of 99.9%, short rod-shaped Nb particles with a purity of 99.9%, and short rod-shaped Al particles with a purity of 99.9%. Select high-purity Ti, V, Zr, Nb, and Al metal single substances, and use 240-mesh coarse sandpaper to grind the particle surface to remove the oxide skin on the surface of the single substance. Use anhydrous ethanol solution ultrasonic oscillation to clean the raw materials and set them aside. Based on the total mass of 40g of each element's raw materials, the weighed masses of the metal particle raw materials Ti, V, Zr, Nb and Al are 19.943g (49.86wt.%), 3.430g (8.58wt.%), 9.246g (23.12wt.%), 6.256g (15.64wt.%) and 1.124g (2.81wt.%), respectively, with an error value of ±0.001g. In addition, due to the low melting point of Al and its boiling point close to the melting point of Nb, 0.056g (5at.%) of Al element is weighed more.

[0078] Step 2: Melting: Place the raw materials prepared in step 1 into an arc melting furnace for melting. Before melting, draw the vacuum degree to 5×10 3 Pa, then fill with high-purity argon gas to a pressure of 0.02 to 0.05 MPa, and then evacuate to a vacuum of 5×10 3 Pa is considered as one purge. After three purges, high-purity argon is filled to a pressure of 0.02 to 0.05 MPa to start smelting. The current during smelting is 200-300A. After each smelting, the ingot needs to be turned over, and the smelting is repeated at least 10 times to obtain an ingot.

[0079] Step 3: Homogenization heat treatment: Place the ingot into a quartz glass tube and evacuate the glass tube to a vacuum degree of 2×10 3 Pa, use hydrogen flame to seal the tube, and then perform homogenization heat treatment. The specific process is: temperature 990℃-1010℃, time 2 hours, water quenching cooling.

[0080] Step 4: Use 240-mesh and 600-mesh coarse sandpaper to polish the surface of the sample after homogenization heat treatment in step 3 to remove the oxide scale, and then perform cold rolling, with a rolling pressure of 80% and 90%, using multiple passes, and each pass has a pressure of 0.1-0.3 mm.

[0081] Step 5: Pre-cut the sample cold-rolled in step 4 to the required size, polish it with 240-mesh and 600-mesh coarse sandpaper to remove the oxide scale, put the polished sample into a quartz glass tube, and draw the vacuum degree of the glass tube to 2×10 3Pa, use hydrogen flame to seal the tube, and then perform recrystallization heat treatment. The specific process is: temperature 740℃-760℃, time 30min, water quenching cooling.

[0082] Figure 1 For the recrystallized Ti in Example 3 60 V 9.7 Zr 14.6 Nb 9.7 Al 6 The XRD diffraction analysis diagram of the lightweight refractory multi-component alloy with high processing and forming ability proves that the alloy exhibits a single body-centered cubic structure in the recrystallized state. Figure 2 For the recrystallized Ti in Example 3 60 V 9.7 Zr 14.6 Nb 9.7 Al 6 The tensile engineering stress-strain curve of the lightweight refractory multi-component alloy with high processing forming ability measured at room temperature shows that the tensile yield strength of Example 3 in the rolling 80% recrystallization process is 717.1 MPa, and the tensile plasticity is 33.5%. The tensile yield strength in the rolling 90% recrystallization process is 812.0 MPa, and the tensile plasticity is 30.2%. Figure 3 The hardness diagrams of Example 3 are measured in the homogenized state, rolled state and recrystallized state respectively. Figure 3 It can be seen that after the rolling process, the hardness of the material increases. At this time, due to the extremely large internal stress caused by plastic processing, recrystallization annealing is required to eliminate the internal stress. Because the regrown grains are finer than the homogenized state, the hardness of the recrystallized state is higher than that of the homogenized state. Fig.10 For the recrystallized Ti in Example 3 60 V 9.7 Zr 14.6 Nb 9.7 Al 6 Microstructure of the lightweight refractory multi-component alloy with high processing and forming capability. In Example 3, no precipitation phase was found at the grain boundary. Fig.11 For the recrystallized Ti in Example 3 60 V 9.7 Zr 14.6 Nb 9.7 Al 6 The electron backscattered diffraction pattern of the lightweight refractory multi-component alloy with high processing and forming ability shows that the average grain size is 48.0μm. Fig.12 For the recrystallized Ti in Example 3 60 V 9.7 Zr 14.6 Nb 9.7 Al 6High-resolution transmission electron microscopy image of a lightweight refractory multi-component alloy with high processing and forming capability. The thumbnail is a Fourier transformed lattice. It can be seen that Example 1 is a single body-centered cubic structure with a relatively obvious diffuse scattering disk (marked with a yellow circle), and a local chemically ordered structure is observed. Fig.13 For the recrystallized Ti in Example 3 60 V 9.7 Zr 14.6 Nb 9.7 Al 6 Inverse Fourier transform diagram of lightweight refractory multi-component alloy with high processing capability, through Fig.12 The yellow circle marked in the thumbnail is inverse Fourier transformed, and the circled lattice in the figure is a local chemical ordered structure. When the material is deformed by force, the generated slip dislocation passes through the local chemical ordered structure, and the dislocation cuts through the structure, which plays a role in hindering the dislocation, so the strength of the material is improved. The dislocation passes through the local chemical ordered structure and then transfers to other atomic planes to complete the proliferation of dislocations and the increase of slip systems, so the plasticity of the material is improved. Fig.17 This is a processing diagram of a lightweight refractory multi-component alloy material with high processing and forming ability, with a rolling pressure of 80%. The three workpieces from top to bottom are the rolling results of Example 3. Fig.17 It can be seen that after 80% rolling, the workpiece has a full contour, a complete surface with few defects, and has excellent ductility and processing capabilities. It can facilitate metal plastic processing (such as forging and extrusion) into the desired shape, thereby improving material utilization. Fig.18 Example 3 homogenized annealed Ti 60 V 9.7 Zr 14.6 Nb 9.7 Al 6 Processing diagram of lightweight refractory multi-component alloy with high processing capability at different rolling reductions, by Fig.13 It can be seen that with the increase of rolling amount, the workpiece is fully extended, and when the rolling reduction ratio is 90%, the elongation reaches 409%.

[0083] Example 4

[0084] This embodiment provides a lightweight, high-strength, high-entropy alloy containing Ti, V, Zr, Nb, and Al elements, the chemical formula of which is Ti 60 V 8.9 Zr 13.2 Nb 8.9 Al 9 , its theoretical density is 5.11g / cm 3 The specific preparation method is as follows:

[0085] Step 1, raw material selection and batching: Select short rod-shaped Ti particles with a purity of 99.9%, short rod-shaped V particles with a purity of 99.9%, short rod-shaped Zr particles with a purity of 99.9%, short rod-shaped Nb particles with a purity of 99.9%, and short rod-shaped Al particles with a purity of 99.9%. Select high-purity Ti, V, Zr, Nb, and Al metal single substances, and use 240-mesh coarse sandpaper to grind the particle surface to remove the oxide skin on the surface of the single substance. Use anhydrous ethanol solution ultrasonic oscillation to clean the raw materials and set them aside. Based on the total mass of 40g of each element's raw materials, the weighed masses of the metal particle raw materials Ti, V, Zr, Nb and Al are 20.520g (51.3wt.%), 3.238g (8.1wt.%), 8.601g (21.5wt.%), 5.906g (14.77wt.%) and 1.735g (4.34wt.%), respectively, with an error value of ±0.001g. In addition, due to the low melting point of Al and its boiling point close to the melting point of Nb, 0.086g (5at.%) of Al element is weighed more.

[0086] Step 2: Melting: Place the raw materials prepared in step 1 into an arc melting furnace for melting. Before melting, draw the vacuum degree to 5×10 3 Pa, then fill with high-purity argon gas to a pressure of 0.02 to 0.05 MPa, and then evacuate to a vacuum of 5×10 3 Pa is considered as one purge. After three purges, high-purity argon is filled to a pressure of 0.02 to 0.05 MPa to start smelting. The current during smelting is 200-300A. After each smelting, the ingot needs to be turned over, and the smelting is repeated at least 10 times to obtain an ingot.

[0087] Step 3: Homogenization heat treatment: Place the ingot into a quartz glass tube and evacuate the glass tube to a vacuum degree of 2×10 3 Pa, use hydrogen flame to seal the tube, and then perform homogenization heat treatment. The specific process is: temperature 990℃-1010℃, time 2 hours, water quenching cooling.

[0088] Step 4: Use 240-mesh and 600-mesh coarse sandpaper to grind the surface of the sample after the homogenization heat treatment in step 3 to remove the oxide scale. Then cold rolling is performed, with a rolling pressure of 80%, multiple passes, and each pass has a pressure of 0.1-0.3 mm.

[0089] Step 5: Pre-cut the sample cold-rolled in step 4 to the required size, polish it with 240-mesh and 600-mesh coarse sandpaper to remove the oxide scale, put the polished sample into a quartz glass tube, and draw the vacuum degree of the glass tube to 2×10 3 Pa, use hydrogen flame to seal the tube, and then perform recrystallization heat treatment. The specific process is: temperature 740℃-760℃, time 30min, water quenching cooling.

[0090] Figure 1 The recrystallized Ti in Example 4 60 V 8.9 Zr 13.2 Nb 8.9 Al 9 The XRD diffraction analysis diagram of the lightweight refractory multi-component alloy with high processing and forming ability proves that the alloy exhibits a single body-centered cubic structure in the recrystallized state. Figure 2 The recrystallized Ti in Example 4 60 V 8.9 Zr 13.2 Nb 8.9 Al 9 The tensile engineering stress-strain curve of the lightweight refractory multi-component alloy with high processing and forming ability measured at room temperature shows that the tensile yield strength of Example 4 is 804.9 MPa and the tensile plasticity is 26.5%. Figure 3 The hardness diagrams of Example 1 are measured in the homogenized state, rolled state and recrystallized state respectively. Figure 3 It can be seen that after the rolling process, the hardness of the material increases. At this time, due to the extremely large internal stress caused by plastic processing, recrystallization annealing is required to eliminate the internal stress. Because the regrown grains are finer than the homogenized state, the hardness of the recrystallized state is higher than that of the homogenized state. Fig.14 Example 4 is the homogenized Ti 60 V 8.9 Zr 13.2 Nb 8.9 Al 9 Microstructure of a lightweight refractory multi-component alloy with high processing capability, where the grains are very coarse. Fig.15 The recrystallized Ti in Example 4 60 V 8.9 Zr 13.2 Nb 8.9 Al 9 Microstructure picture of lightweight refractory multi-component alloy with high processing and forming capability. No precipitation phase was found at the grain boundary in Example 4. Fig.16 The recrystallized Ti in Example 4 60 V 8.9 Zr 13.2 Nb 8.9 Al 9 The electron backscattered diffraction pattern of the lightweight refractory multi-component alloy with high processing and forming capability shows that the average grain size is 62.1μm and the grain structure is fully refined. Fig.17 This is a processing diagram of a lightweight refractory multi-component alloy material with high processing and forming ability, with a rolling pressure of 80%. The four workpieces from top to bottom are the rolling results of Example 4. Fig.17It can be seen that after 80% rolling, the workpiece has a full contour, a complete surface with few defects, and has excellent ductility and processing capabilities. It can facilitate metal plastic processing (such as forging and extrusion) into the desired shape, thereby improving material utilization.

[0091] The above is only a preferred embodiment of the present invention, which certainly cannot be used to limit the scope of rights of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and changes can be made without departing from the principle of the present invention, and these improvements and changes are also regarded as the protection scope of the present invention.

Claims

1. A lightweight refractory multi-component alloy material with high processing and forming capability, characterized in that: The alloy material comprises the following components in atomic percentage: Ti: 60 at.%, V: 8.9-11.5 at.%, Zr: 13.2-17 at.%, Nb: 8.9-11.5 at.%, Al: 0-9 at.%, and the grain size of the alloy material is 39.3-62.1 μm.

2. The lightweight refractory multi-component alloy material with high processing and forming capability according to claim 1, characterized in that: The following components are included in atomic percentage: Ti: 60 at.%, V: 8.9-10.6 at.%, Zr: 13.2-15.8 at.%, Nb: 8.9-10.6 at.%, Al: 3-9 at.%.

3. The lightweight refractory multi-component alloy material with high processing and forming capability according to claim 1, characterized in that: The atomic percentages of V, Zr and Nb are 0.9-1.1:1.4-1.6:0.9-1.

1.

4. The lightweight refractory multi-component alloy material with high processing and forming capability according to claim 1, characterized in that: The density of the alloy material is 5.11-5.50 g / cm 3 , the tensile yield strength is 638.3-853.4MPa, and the room temperature tensile plasticity is 24.3%-33.5%.

5. The lightweight refractory multi-component alloy material with high processing and forming capability according to claim 1, characterized in that: The alloy material is a single body-centered cubic structure.

6. A method for preparing a lightweight refractory multi-component alloy material with high processing and forming capability as claimed in any one of claims 1 to 5, characterized in that: The following steps are involved: (1) Remove impurities and oxide scale from the surface of the raw material block and clean it, and weigh the required raw material mass; (2) Melting the raw materials; (3) The smelted material is subjected to homogenization heat treatment and then cooled; (4) cold rolling the cooled material; (5) The cold-rolled material is subjected to recrystallization heat treatment, and the alloy material is obtained after cooling.

7. The method for preparing a lightweight refractory multi-component alloy material with high processing and forming capability according to claim 6, characterized in that: In step (2), an arc melting furnace is used for melting, and the vacuum degree is drawn to 5×10 3 Pa, then fill with high-purity argon gas to a pressure of 0.02 to 0.05 MPa, and then evacuate to a vacuum of 5×10 3 Pa, repeat several times, fill with high-purity argon gas to the pressure of 0.02 to 0.05MPa and start smelting. The current during smelting is 200-300A; turn over after each smelting, and repeat the smelting for at least 10 times.

8. The method for preparing a lightweight refractory multi-component alloy material with high processing and forming capability according to claim 6, characterized in that: In step (3), the smelted material is vacuum sealed and then heat treated at a temperature of 990-1010° C. for 1-3 hours, followed by water quenching.

9. The method for preparing a lightweight refractory multi-component alloy material with high processing and forming capability according to claim 6, characterized in that: In step (4), the rolling pressure is 80%-90%, and multiple passes are used, with each pass pressing 0.1-0.3 mm.

10. The method for preparing a lightweight refractory multi-component alloy material with high processing and forming capability according to claim 6, characterized in that: In step (5), the temperature of the recrystallization heat treatment is 740-760° C., the time is 25-35 min, and the water quenching is performed.

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