High-toughness refractory multi-component alloy and preparation method thereof
Through the chemical composition of Ti25(Zr, Nb)75-xTax and vacuum arc smelting technology, a high-strength and tough refractory multi-component alloy was prepared, which solved the problems of high density, irreconcilability and toughness in the prior art, and realized The effect of superior performance and reduced cost has wide application prospects.
Patent Information
- Application Number
- CN202411421273.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-10-12
- Publication Date
- 2024-12-24
AI Technical Summary
The existing refractory multi-component alloys have high density, difficult to harmonize strength and toughness, high material cost and difficult processing, and cannot be widely promoted and used.
Using the chemical composition of Ti25(Zr, Nb)75-xTax, it is prepared in a high vacuum environment through vacuum arc smelting technology, and the melting current and vacuum degree are regulated, and multiple remelting is carried out to ensure the uniformity of components and tissue uniformity. It is prepared. High-strength and tough refractory multi-component alloy.
It realizes relatively lightweight, high strength, high hardness and high plasticity refractory alloys, with better performance than most refractory multi-component alloys, reduces cost requirements, and is suitable for the preparation of high-purity materials, with broad application prospects .
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Figure CN119177369A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the technical field of alloy materials, and in particular to a high-strength and tough refractory multi-component alloy and a preparation method thereof. Background Art
[0002] Multi-principal-element multi-component alloy is an emerging alloy material that has developed rapidly and has become a research hotspot in the field of metal materials. Its design concept breaks the traditional alloy design concept based on mixing enthalpy and opens up a new research field for metal materials.
[0003] The inherent high entropy effect of multi-component alloys can inhibit the appearance of the second phase between metals and form a simple solid solution, thus having many excellent properties and characteristics. The type and content of alloying elements in multi-component alloys have a significant effect on the phase stability, composition uniformity and microstructure of multi-component alloys, thereby affecting the comprehensive performance of multi-component alloys, and it is expected to achieve a "cocktail effect". At the same time, due to the inherent "lattice distortion effect" of multi-component alloys, the addition of alloying elements will affect the original lattice of multi-component alloys. These effects will change the toughening mechanism of multi-component alloys. Therefore, through reasonable composition design, multi-component alloys can have excellent properties, such as high strength, high hardness, high temperature oxidation resistance, corrosion resistance, etc., which can meet the needs of many special environments. For example, in aerospace, materials need to have characteristics such as high strength and high hardness; the hazardous chemicals transportation industry has the need for high corrosion resistance as a transportation or storage carrier; the rail transportation industry requires high wear resistance and high stiffness materials as rail load-bearing. The excellent mechanical properties enable multi-component alloys to play a unique role in special service environments.
[0004] The application of metal materials tends to be more lightweight. Military, industrial, aerospace, transportation and other fields are in urgent need of lightweight alloy materials with superior performance. However, traditional refractory multi-component alloys are mostly composed of high-melting-point metal elements. However, these multi-component alloys have the characteristics of high density, high melting point, difficulty in balancing strength and plasticity, and difficulty in smelting. For example, refractory high-temperature alloys with single-phase BCC structure such as MoNbTaW and MoNbTaVW often have high compressive strength. The compressive yield strength at 1600°C is 405MPa and 477MPa, respectively, which is significantly higher than traditional high-temperature alloys such as Inconel718 and Haynes230. However, the single-phase BCC structure makes the room temperature plasticity of such alloys often poor and difficult to process. For example, the room temperature plasticity of the above two alloys is 2.6% and 1.7%, respectively, which is poorer than other engineering alloys. Although the alloy has excellent high temperature resistance, it still has problems such as poor plasticity, high density, expensive composition, and difficult preparation.
[0005] At present, the refractory multi-component alloys in the existing technology still have problems such as high density, difficulty in reconciling strength and toughness, high material cost and great processing difficulty, and cannot be widely promoted and used; therefore, in view of the shortcomings in the performance and smelting methods of the existing refractory multi-component alloys, it is very urgent to develop a multi-component alloy with superior performance in strength, plasticity, hardness and cost and its manufacturing method. Summary of the invention
[0006] In order to solve the above technical problems, the present invention provides a high-strength and high-toughness refractory multi-component alloy and a preparation method thereof.
[0007] A method for preparing a high-strength and high-toughness refractory multi-component alloy comprises the following steps: (1) The multi-component alloy includes the following components: Ti 25 (Zr, Nb) 75-x Ta x ; Weigh Ti particles, Zr particles, Nb particles, and Ta particles with a purity exceeding 99.95% by atomic percentage; (2) Using Ti / Zr balls as oxygen absorbers, the raw material particles are respectively prepared into TiZr and NbTa master alloys, and are loaded into a vacuum arc melting furnace in order from low to high melting points; (3) Fill in inert gas argon for gas washing and adjust the vacuum degree of the vacuum arc melting furnace; (4) Adjust the melting current to 40A to start the arc, adjust the melting current, and remelt the two intermediate alloys at least 6 times under argon protection to ensure uniform structure. The ingot must be turned upside down each time. During the remelting process, the current must be gradually increased from small to large for 3-5 minutes until it is completely molten. During this period, the melting state of the ingot must be paid attention to at all times to avoid explosion. Then the current can be increased quickly to a flowing molten drop state. (5) Under the furnace chamber environment mentioned in step (3), according to the operating procedures in step (4), the two master alloys are sequentially charged into a vacuum arc melting furnace in order of melting point from low to high to melt them together, remelted 8 to 10 times and then cooled under vacuum to obtain the multi-component alloy.
[0008] Furthermore, in step (3), the vacuum degree of the vacuum arc melting furnace is adjusted to 10 -4 Argon is used as protective gas.
[0009] Furthermore, in step (4), the smelting current is regulated by increasing the current from low to high to melt the granular raw material to prevent splashing. The current is 80-120 A, which should be based on the melting of the raw material. After the raw material is melted into a droplet state without splashing, the current is increased to 280-320 A, based on the observation of flowing molten droplets (TiZr master alloy has a lower melting point, so the current parameter can be slightly reduced).
[0010] Furthermore, in step (5), after the two intermediate alloys are fused, the two intermediate alloys must be turned upside down each time during the remelting process, and the current must be gradually increased from small to large for 3-5 minutes until it is completely molten. Then the current can be increased quickly to a flowing molten droplet state. During this period, attention must be paid to whether the melting state of the ingot is stable to avoid explosion.
[0011] Furthermore, the remelting time of steps (4) and (5) is as follows: each time the two master alloys are fused and remelted, the sample needs to be kept in a flowing molten droplet state for 2-3 minutes to promote uniform composition.
[0012] A high-strength and tough refractory multi-component alloy is prepared by the above-mentioned preparation method of the high-strength and tough refractory multi-component alloy, wherein the chemical composition of the multi-component alloy is Ti 25 (Zr, Nb) 75-x Ta x , wherein the value of x ranges from 6 to 8, and the high-strength and tough refractory multi-component alloy is composed of four high-melting-point elements, Ti, Zr, Nb, and Ta, and the four elements are all in atomic percentage, and the sum of the elements is 100.
[0013] Further, in terms of atomic percentage, the x is 6, Ti 25 (Zr, Nb) 69 Ta6, the sum of the elements is 100.
[0014] Furthermore, the refractory multi-component alloy has a melting point of 2092° C., a single BCC crystal structure, a yield strength of 1220 MPa, an ultimate compressive strength of 1500 MPa, a compression strain rate greater than 50%, and a Vickers hardness of 363 HV.
[0015] Further, in terms of atomic percentage, the x is 8, Ti 25 (Zr, Nb) 67 Ta8, the sum of the elements is 100.
[0016] Furthermore, the refractory multi-component alloy has a melting point of 2109° C., a single BCC crystal structure, a yield strength of 1130 MPa, an ultimate compressive strength of 1340 MPa, a compression strain rate greater than 50%, and a Vickers hardness of 338 HV.
[0017] Compared with the prior art, the advantages of the present invention are: (1) Compared with the existing refractory multi-component alloy system, the present invention adopts relatively light TiZr elements and NbTa elements with higher melting points, and through composition control, it maintains a relatively light refractory alloy with high strength and toughness, and its performance exceeds the mechanical properties of most refractory multi-component alloys (see the comparative data in Table 1); the higher TiZrNb elements and certain Ta elements reduce its cost requirements and ensure its excellent performance, and has broad application prospects; (2) Compared with the existing smelting technology, the present invention adopts vacuum arc melting and performs preparation in a high vacuum environment, which is suitable for the preparation of high-purity materials, and the equipment is widely used and is one of the contemporary advanced material preparation methods; the present invention selects appropriate process parameters and applies them to prepare this high-strength and toughness refractory multi-component alloy; (3) Compared with the refractory multi-component alloy of the Ti-Zr-Nb-Ta system, the present invention has higher strength and hardness, and has broader prospects in future practical applications. BRIEF DESCRIPTION OF THE DRAWINGS
[0018] Figure 1 This is the XRD pattern of the alloy prepared in Example 1 of the present invention.
[0019] Figure 2 This is a microstructure diagram of the alloy prepared in Example 1 of the present invention.
[0020] Figure 3 This is the room temperature compressive stress-strain curve of the alloy prepared in Example 1 of the present invention.
[0021] Figure 4 This is the XRD pattern of the alloy prepared in Example 2 of the present invention.
[0022] Figure 5 This is a microstructure diagram of the alloy prepared in Example 2 of the present invention.
[0023] Figure 6 This is the room temperature compressive stress-strain curve of the alloy prepared in Example 2 of the present invention. DETAILED DESCRIPTION
[0024] In order to make the purpose, technical means and advantages of the present invention more clear, the following drawings and embodiments further illustrate the present invention in detail. It should be noted that the following embodiments are only used to explain the present invention and are not used to limit the present invention. Example 1
[0025] A method for preparing a high-strength and high-toughness refractory multi-component alloy comprises the following steps: (1) After the surface oxide scale of Ti particles, Zr particles, Nb particles, and Ta particles with a purity exceeding 99.95% is polished, they are cleaned by ultrasonic vibration and then dried, and weighed according to the atomic ratio of 25:34.5:34.5:6.
[0026] (2) The raw material particles are respectively prepared into TiZr and NbTa master alloys, and are loaded into a water-cooled copper crucible of a vacuum arc melting furnace in order from low to high melting points, with Ti / Zr balls used as oxygen absorbers, and the furnace chamber is closed.
[0027] (3) Fill the furnace chamber with argon gas for gas washing, and then evacuate the vacuum arc melting furnace to a vacuum degree of 10 -4 , filled with argon as protective gas.
[0028] (4) Adjust the current to 40A for arc striking, and increase the current from low to high to melt the granular material to prevent splashing. The current size is 80-120A, which should be based on the melting of the raw materials; after the melting is in droplet state and there is no splashing, start to increase the current to 230-320A, based on the observation of flowing molten droplets (TiZr intermediate alloy has a lower melting point, so the current parameter can be slightly reduced), so that the metal droplets remain in a flowing molten state; use argon as a protective gas to remelt the two intermediate alloys at least 6 times to ensure uniform structure (each remelting requires the sample to remain in a flowing molten droplet state for 2-3 minutes), and the ingot must be turned upside down for each remelting; during the remelting process, the current must be gradually increased from small to large, and the time is 3-5 minutes until it is completely molten. Then the current can be increased faster to a flowing molten droplet state. During this period, attention must be paid to the melting state of the ingot to avoid explosion.
[0029] (5) Ensure the furnace chamber environment required in step (3), and according to the operating procedures in step (4), load the two master alloys into the vacuum arc melting furnace in order of melting point from low to high to melt them. After the two master alloys are melted, they are turned over during each remelting process. Special attention must be paid to the turning remelting process. The current must be gradually increased from small to large for 3-5 minutes until it is completely molten. Then the current can be increased to a flowing molten droplet state. During this period, the melting state of the ingot must be paid attention to at all times to avoid explosion. After 8-10 remelting times, the ingot is cooled under vacuum (the sample must be kept in a flowing molten droplet state for 2-3 minutes each time it is remelted) to obtain the multi-component alloy.
[0030] like Figure 1-3 As shown, XRD phase analysis was performed on the multi-component alloy ingot, and it was determined that it had a single BCC crystal structure. The mechanical properties test results showed that the high-strength and toughness refractory multi-component alloy had a room temperature yield strength of 1220 MPa, an ultimate compressive strength of 1500 MPa, a compressive strain rate greater than 50%, and a Vickers hardness of 363 HV.
[0031] Example 2 A method for preparing a high-strength and high-toughness refractory multi-component alloy comprises the following steps: (1) After the surface oxide scale of Ti particles, Zr particles, Nb particles, and Ta particles with a purity exceeding 99.95% is polished, they are cleaned by ultrasonic vibration and then dried, and weighed according to the atomic ratio of 25:33.5:33.5:8.
[0032] (2) The raw material particles are respectively prepared into TiZr and NbTa master alloys, and are loaded into a water-cooled copper crucible of a vacuum arc melting furnace in order from low to high melting points, with Ti / Zr balls used as oxygen absorbers, and the furnace chamber is closed.
[0033] (3) Fill the furnace chamber with argon gas for gas washing, and then evacuate the vacuum arc melting furnace to a vacuum degree of 10 -4 , filled with argon as protective gas.
[0034] (4) Adjust the current to 40A for arc striking, and increase the current from low to high to melt the granular material to prevent splashing. The current size is 80-120A, which should be based on the melting of the raw materials; after the melting is in droplet state and there is no splashing, start to increase the current to 230-320A, based on the observation of flowing molten droplets (TiZr intermediate alloy has a lower melting point, so the current parameter can be slightly reduced), so that the metal droplets remain in a flowing molten state; use argon as a protective gas to remelt the two intermediate alloys at least 6 times to ensure uniform structure (each remelting requires the sample to remain in a flowing molten droplet state for 2-3 minutes), and the ingot must be turned upside down for each remelting; during the remelting process, the current must be gradually increased from small to large, and the time is 3-5 minutes until it is completely molten. Then the current can be increased faster to a flowing molten droplet state. During this period, attention must be paid to the melting state of the ingot to avoid explosion.
[0035] (5) Ensure the furnace chamber environment required in step (3), and according to the operating procedures in step (4), load the two master alloys into the vacuum arc melting furnace in order of melting point from low to high to melt them. After the two master alloys are melted, they are turned over during each remelting process. Special attention must be paid to the turning remelting process. The current must be gradually increased from small to large for 3-5 minutes until it is completely molten. Then the current can be increased to a flowing molten droplet state. During this period, the melting state of the ingot must be paid attention to at all times to avoid explosion. After 8-10 remelting times, the ingot is cooled under vacuum (the sample must be kept in a flowing molten droplet state for 2-3 minutes each time it is remelted) to obtain the multi-component alloy.
[0036] like Figure 4-6 As shown, XRD phase analysis of the ingot confirmed that it was a single BCC crystal structure. The mechanical properties test results show that the room temperature yield strength of the high-strength and tough refractory multi-component alloy is 1130MPa, the ultimate compressive strength is 1340MPa, the compression strain rate is greater than 50%, and the Vickers hardness is 338HV.
[0037]
[0038] Table 1 compares the performance of the Ti-Zr-Nb-Ta alloy of the present invention with that of a typical high temperature resistant alloy system.
Claims
1. A method for preparing a high-strength and tough refractory multi-component alloy, characterized in that: The following steps are involved: (1) The multi-component alloy includes the following components: Ti 25 (Zr, Nb) 75-x Ta x ; Weigh Ti particles, Zr particles, Nb particles, and Ta particles with a purity exceeding 99.95% by atomic percentage; (2) Using Ti / Zr balls as oxygen absorbers, the raw material particles are respectively prepared into TiZr and NbTa master alloys, and are loaded into a vacuum arc melting furnace in order from low to high melting points; (3) Filling argon gas for washing and adjusting the vacuum degree of the vacuum arc melting furnace; (4) The current is adjusted to 40A for arc initiation, and the melting current is adjusted. Under the protection of argon, the two intermediate alloys are remelted at least 6 times to ensure uniform structure. The ingot must be turned upside down each time. During the remelting process, the current must be gradually increased from small to large for 3-5 minutes until it is completely molten. During this period, the melting state of the ingot must be paid attention to at all times to avoid explosion. Then the current can be increased quickly to a flowing molten drop state. (5) Under the furnace chamber environment mentioned in step (3), according to the operating procedures in step (4), the two master alloys are sequentially charged into a vacuum arc melting furnace in order of melting point from low to high to be melted and fused, and then remelted 8 to 10 times and cooled under vacuum to obtain the multi-component alloy.
2. The method for preparing a high-strength and tough refractory multi-component alloy according to claim 1, characterized in that: Step (3) adjusts the vacuum degree of the vacuum arc melting furnace to 10 -4 Argon is used as protective gas.
3. The method for preparing a high-strength and tough refractory multi-component alloy according to claim 1, characterized in that: Step (4) regulating the smelting current: increasing the current from low to high to melt the granular raw materials to prevent splashing, the current size is 80-120A, which should be based on the melting condition of the raw materials; When the melt is in droplet state and there is no splashing, start to increase the current to 280-320A, based on the observation of flowing melt droplets.
4. The method for preparing a high-strength and tough refractory multi-component alloy according to claim 1, characterized in that: Step (5) Fusion of the two master alloys: After the two master alloys are fused, they must be turned upside down during each remelting process. The current must be gradually increased from small to large for 3-5 minutes until they are completely molten. The current can then be increased to a flowing molten droplet state. During this period, attention must be paid to whether the ingot melting state is stable to avoid explosion.
5. The method for preparing a high-strength and tough refractory multi-component alloy according to claim 1, characterized in that: Remelting time of steps (4) and (5): Each time the two master alloys are melted, the sample must be kept in a flowing molten droplet state for 2-3 minutes to promote uniform composition.
6. A high-strength and tough refractory multi-component alloy, prepared by the method for preparing a high-strength and tough refractory multi-component alloy according to any one of claims 1 to 5, characterized in that: The chemical composition of the multi-component alloy is Ti 25 (Zr, Nb) 75-x Ta x , wherein the value of x ranges from 6 to 8, and the high-strength and tough refractory multi-component alloy is composed of four high-melting-point elements, Ti, Zr, Nb, and Ta, wherein the four elements are all in atomic percentages, and the sum of the elements is 100.
7. The high-strength and tough refractory multi-component alloy according to claim 6, characterized in that: In terms of atomic percentage, the x is 6, Ti 25 (Zr, Nb) 69 Ta6, the sum of the elements is 100.
8. The high-strength and tough refractory multi-component alloy according to claim 7, characterized in that: The refractory multi-component alloy has a melting point of 2092° C., a single BCC crystal structure, a yield strength of 1220 MPa, an ultimate compressive strength of 1500 MPa, a compression strain rate greater than 50%, and a Vickers hardness of 363 HV.
9. The high-strength and tough refractory multi-component alloy according to claim 6, characterized in that: In terms of atomic percentage, the x is 8, Ti 25 (Zr, Nb) 67 Ta8, the sum of the elements is 100.
10. The high-strength and tough refractory multi-component alloy according to claim 8, characterized in that: The refractory multi-component alloy has a melting point of 2109° C., a single BCC crystal structure, a yield strength of 1130 MPa, an ultimate compressive strength of 1340 MPa, a compression strain rate greater than 50%, and a Vickers hardness of 338 HV.