CN-121976107-A - High-entropy alloy with strength of more than 980MPa at 1200 ℃ and preparation method and application thereof

Abstract

The invention relates to the technical field of metal materials, and particularly discloses a high-entropy alloy with strength of more than 980MPa at 1200 ℃ and a preparation method and application thereof. The high-entropy alloy composition provided by the invention is WMoTaTi x Nb y B z , wherein the value of x is 0-1, the value of y is 0-1, and the value of z is 0-0.1. The high-entropy alloy material is prepared by adopting a laser/electron beam selective melting additive manufacturing method, so that the application requirements of high temperature resistance and oxidation resistance of the high-entropy alloy material are met, the stable use temperature of the developed high-entropy alloy material reaches 1200 ℃, and the compression strength of the developed high-entropy alloy material reaches over 980 MPa.

Inventors

• CHEN WEI
• Wan Hongyuan
• YANG YANG
• ZHANG ZEXIN
• ZHANG ZHIBO

Assignees

• 中国航空制造技术研究院

Dates

Publication Date

20260505

Application Date

20260105

Claims (10)

1. 1. A high-entropy alloy with the strength of over 980MPa at 1200 ℃ is characterized by comprising WMoTaTi x Nb y B z , wherein the value of x is 0-1, the value of y is 0-1, and the value of z is 0-0.1.
2. 2. The high-entropy alloy according to claim 1, wherein x is 0.1 to 1, y is 0.1 to 1, and z is 0.01 to 0.05.
3. 3. The high-entropy alloy according to claim 2, wherein x is 0.4 to 0.6, y is 0.4 to 0.6, and z is 0.01 to 0.03.
4. 4. The high-entropy alloy of claim 3, wherein x is 0.5, y is 0.5, and z is 0.02.
5. 5. A method of preparing a high entropy alloy according to any one of claims 1 to 4, wherein an additive manufacturing method is employed, comprising the steps of: S1, pre-placing high-entropy alloy powder materials in a material cylinder in a forming cabin, wherein the high-entropy alloy powder materials are prepared according to the composition of the prepared high-entropy alloy materials; s2, placing the formed substrate into a sealed forming cabin; s3, filling argon into the forming cabin, or vacuumizing the forming cabin; S4, preheating the forming substrate; s5, starting beam current to form, wherein a beam source for additive manufacturing is laser or electron beam; S6, cooling to below 100 ℃ after forming is completed, and obtaining the high-entropy alloy with the strength of more than 980MPa at 1200 ℃.
6. 6. The method according to claim 5, wherein in the step S3, the argon gas is high purity argon gas with purity not less than 99.99%.
7. 7. The method according to claim 5, wherein the vacuum degree of the vacuum in step S3 is 1X 10 -3 Pa~3×10 -3 Pa.
8. 8. The method according to claim 5, wherein the preheating temperature in step S4 is 80-850 ℃.
9. 9. The method according to any one of claims 5 to 8, wherein in step S1, the powder particle size of the high-entropy alloy powder material is 10 to 105 μm.
10. 10. Use of the high-entropy alloy according to any one of claims 1-4 in aeroengines.

Description

High-entropy alloy with strength of more than 980MPa at 1200 ℃ and preparation method and application thereof Technical Field The invention relates to the technical field of metal materials, in particular to a high-entropy alloy material with strength of more than 980MPa at 1200 ℃, and also relates to a preparation method and application thereof. Background Along with the continuous improvement of the thrust-weight ratio of the aeroengine, the hot end components such as the combustion chamber and the like provide higher requirements on the light weight, high temperature resistance and durability of structural materials, and the traditional nickel-based superalloy has developed to the limit, and the complex structure also provides great challenges for the traditional manufacturing technology. The high-entropy alloy material is a novel material with excellent high-temperature specific strength and can be used for a long time above 1000 ℃, and the high-entropy alloy material is expected to replace nickel-based superalloy to be applied to a new generation of aeroengines by means of additive manufacturing technology. The high-entropy alloy self-concept is proposed for only less than 20 years so far, and is still in the early stage of basic research and application exploration. Among them, refractory high-entropy alloy represented by NbMoTaW, nbMoTaWV, tiZrHfNbTa, WTaVCr, nbMoTiAl, moNbHfZrTi has very excellent high-temperature mechanical properties and is considered as the most potential high-temperature alloy substitute material. In particular, the yield strength of two refractory high-entropy alloys, namely NbMoTaW and NbMoTaWV, is still as high as 405MPa and 477MPa respectively at 1600 ℃, and is superior to that of the most advanced Japanese fifth-generation single-crystal superalloy TMS-196, but the room-temperature elongation of the two refractory high-entropy alloys is only 2.6%, and the high-plasticity matching is poor. Except the two types of alloys, the strength of the rest high-entropy alloys is sharply reduced at the temperature higher than 800 ℃, the oxidation weight gain phenomenon of the alloys is very serious, the oxidation resistance is extremely poor, and the diffusion of oxygen impurities into the matrix cannot be prevented. Therefore, how to prepare refractory high-entropy alloy with excellent formability and high-temperature performance is one of the most challenging research subjects in the current metal material manufacturing field. Disclosure of Invention First, the technical problem to be solved The invention aims to solve the technical problem of providing a high-entropy alloy with high temperature resistance and high strength, and a preparation method thereof. (II) technical scheme In order to solve the technical problems, the invention designs a novel high Wen Gaoshang alloy, and adopts a laser/electron beam selective melting additive manufacturing method to form the high-entropy alloy material, so that the application requirements of high temperature resistance and oxidation resistance of the high-entropy alloy material are met, the developed high-entropy alloy material can be stably used in a high-temperature environment of 1200 ℃, and the high-temperature compression strength reaches 980MPa or above. In the first aspect, the invention provides a component design scheme of a high-entropy alloy with the strength of more than 980MPa at 1200 ℃, wherein the component composition of the high-entropy alloy is WMoTaTi xNbyBz, the value of x is 0-1, the value of y is 0-1, and the value of z is 0-0.1. Specifically, in the high-entropy alloy, W (tungsten, melting point 3410 ℃) is used as a high-melting point element to provide high-temperature strength and creep resistance of the alloy to form a stable BCC solid solution matrix, and Mo (molybdenum, melting point 2620 ℃) is used for further enhancing the high-temperature strength of the alloy, improving oxidation resistance and strengthening the matrix in a synergistic effect with W. Ta (tantalum, melting point 3017 ℃ C.) improves the high temperature strength and corrosion resistance of the alloy, particularly oxidation resistance. Ti (titanium) with melting point of 1668 ℃ and proper amount of titanium can improve the plasticity and oxidation resistance of alloy and promote the formation of compact oxide layer. Nb (niobium, melting point 2477 ℃) is similar to Ti, and can improve the plasticity and oxidation resistance of the alloy while maintaining high-temperature strength. B (boron) is used as trace additive element, and is biased to grain boundary, so that the grain boundary strength is improved, the creep resistance is improved, and meanwhile, the formation of a compact oxide layer is promoted, and the oxidation resistance is enhanced. As one embodiment of the invention, the value of x is 0.1-1, the value of y is 0.1-1, and the value of z is 0.01-0.05. The component range can improve the plasticity and oxidation resistance of the alloy wh