CN-117004863-B - Refractory high-entropy alloy with high plasticity and high toughness and preparation method thereof

Abstract

The invention relates to the technical field of alloy materials, in particular to a refractory high-entropy alloy with high plasticity and high toughness and a preparation method thereof. The refractory high-entropy alloy comprises Hf, nb and Ti or comprises Hf, nb, ti and X, wherein X is one or more selected from Ta, zr, mo or V, and the refractory high-entropy alloy has a BCC structural crystal face. The invention aims to obtain refractory high-entropy alloy with high strength and high fracture toughness by adjusting the proportion of different refractory metals.

Inventors

• ZHOU LIHUA
• LI HONGYA
• CHEN JIANG
• NIU SHUTONG
• HUA QIANG
• JIANG YUEFENG
• LEI ZHEN
• LI WENTENG

Assignees

• 中核四0四有限公司

Dates

Publication Date

20260508

Application Date

20230630

Claims (8)

1. 1. The refractory high-entropy alloy with high plasticity and high toughness is characterized in that the constituent elements of the refractory high-entropy alloy are Hf, nb and Ti, or the constituent elements of the refractory high-entropy alloy are Hf, nb, ti and X, wherein X is one or more selected from Ta, zr, mo or V; The refractory high-entropy alloy is a BCC structure crystal face and a HCP structure crystal face; The refractory high-entropy alloy comprises 55-80% of Hf, 0-30% of Ta, 0-20% of Zr, 15-35% of Nb, 10-20% of Ti, 0-15% of Mo and 0-15% of V, wherein the sum of the atomic percentages of all elements in the refractory high-entropy alloy is 100%; The refractory high-entropy alloy with high plasticity and high toughness is prepared by the following method: (S1) placing the pretreated Hf, ta, zr, nb, ti, mo and V metal raw materials in the order from low melting point to high melting point to obtain a prefabricated raw material; And (S2) respectively placing the pure Ti and the prefabricated raw materials prepared in the step (S1) into a smelting furnace, pre-smelting the pure Ti after post-treatment to consume oxygen in the smelting furnace, and smelting the prefabricated raw materials to obtain the refractory high-entropy alloy with high plasticity and high toughness.
2. 2. The refractory high-entropy alloy with high plasticity and high toughness according to claim 1, wherein in step (S1), the pretreatment is an ultrasonic cleaning followed by a drying treatment.
3. 3. The refractory high-entropy alloy with high plasticity and toughness according to claim 1, wherein in step (S2), the post-treatment is to introduce high-purity argon after vacuumizing the melting furnace; Vacuumizing until the vacuum degree of the furnace chamber of the smelting furnace reaches below 9 multiplied by 10 -3 Pa; and introducing high-purity argon to the pressure of the furnace chamber of the smelting furnace to reach 0.01 Pa-0.1 Pa.
4. 4. A refractory high-entropy alloy with high plasticity and high toughness according to claim 3, wherein the introduction of high-purity argon is repeated for more than 3 times after the vacuum pumping, and the pressure of the first introduction of high-purity argon to the furnace chamber of the smelting furnace reaches 0.06Pa.
5. 5. The refractory high-entropy alloy with high plasticity and high toughness according to claim 1, wherein in step (S2), the number of times of pure Ti melting is 2 to 5.
6. 6. The refractory high-entropy alloy of claim 5, wherein the current is 300A and the voltage is 5V for 3min during pure Ti smelting.
7. 7. The refractory high-entropy alloy with high plasticity and high toughness according to claim 1, wherein in step (S3), the number of times of melting the preform is 3 or more; The prefabricated raw material smelting process comprises a non-magnetic stirring smelting process and a magnetic stirring smelting process.
8. 8. The refractory high-entropy alloy with high plasticity and high toughness according to claim 7, wherein the number of times of non-magnetic stirring smelting is 2 and the number of times of magnetic stirring smelting is more than 1; In the process of smelting the prefabricated raw materials, the current is 400-550A, the voltage is 10-18V, the magnetic separation stirring current is 0-5A, and the time is 3min.

Description

Refractory high-entropy alloy with high plasticity and high toughness and preparation method thereof Technical Field The invention relates to the technical field of alloy materials, in particular to a refractory high-entropy alloy with high plasticity and high toughness and a preparation method thereof. Background With the rapid development of high and new technologies, particularly in the fields of machinery, chemical industry, nuclear power and the like, service conditions of related parts are more severe, and the traditional alloy with single performance is difficult to meet application requirements in the related engineering field. Therefore, developing a novel alloy having high strength, high toughness, and high wear resistance is an effective approach to solve the above problems. Taiwan scholars She Junwei break the design concept of the traditional alloy, put forward the design concept of the high-entropy alloy, and the high-entropy alloy has high entropy effect, lattice distortion effect, delayed diffusion effect and cocktail effect, so that the high-entropy alloy has better mechanical property, wear resistance, corrosion resistance, high temperature resistance and irradiation resistance, and has extremely wide application prospect in the engineering field. The high-entropy alloy comprises FCC structure high-entropy alloy, BCC structure high-entropy alloy and HCP structure high-entropy alloy. The refractory high-entropy alloy with the BCC structure takes Ti, ta, nb, mo, hf, V, zr refractory metals such as W and the like as main components, and has the advantages of high melting point, high yield strength, good high-temperature performance and the like, thereby having great application potential in the field of high-temperature materials. However, the existing refractory high-entropy alloy generally has the defects of extremely poor room-temperature plasticity, extremely low fracture toughness and the like, so that the refractory high-entropy alloy is extremely easy to generate catastrophic consequences such as brittle fracture and the like when being used as a part under the working conditions of heavy load, impact and the like, and the application range of the refractory high-entropy alloy is extremely limited. Therefore, how to break through the technical bottleneck of poor room temperature plasticity and toughness of refractory high-entropy alloy, it has become an urgent need to develop refractory high-entropy alloy with higher strength, good plasticity and toughness. Disclosure of Invention In order to solve the above problems (the problem that the refractory high-entropy alloy has poor room temperature plasticity and extremely low fracture toughness), the object of the present invention is to provide a refractory high-entropy alloy having high plasticity and high toughness, and a method for producing the same. The invention mainly adjusts the proportion of different refractory metals to obtain the refractory high-entropy alloy with high strength and high fracture toughness. The aim of the invention can be achieved by the following technical scheme: The first object of the present invention is to provide a refractory high-entropy alloy having high plasticity and high toughness, wherein the constituent elements of the refractory high-entropy alloy are Hf, nb and Ti, or the constituent elements of the refractory high-entropy alloy are Hf, nb, ti and X, wherein X is one or more selected from Ta, zr, mo or V; The refractory high-entropy alloy has a BCC structural crystal plane. In one embodiment of the invention, the refractory high-entropy alloy comprises 45-80% of Hf, 0-30% of Ta, 0-35% of Zr, 3-35% of Nb, 0.5-20% of Ti, 0-15% of Mo and 0-15% of V. A second object of the present invention is to provide a method for preparing a refractory high-entropy alloy having high plasticity and high toughness, comprising the steps of: (S1) placing the pretreated Hf, ta, zr, nb, ti, mo and V metal raw materials in the order from low melting point to high melting point to obtain a prefabricated raw material; (S2) placing pure Ti (which is not a part of refractory high-entropy alloy and aims at consuming oxygen in a smelting furnace in the further smelting process) and the prefabricated raw materials prepared in the step (S1) into the smelting furnace respectively, pre-smelting the pure Ti after post-treatment, and smelting the prefabricated raw materials to obtain the refractory high-entropy alloy with high plasticity and high toughness. In one embodiment of the present invention, in the step (S1), the metal raw material is a rod-like, block-like, sheet-like, columnar or irregularly shaped particle other than powder. In one embodiment of the present invention, in step (S1), the pretreatment is an ultrasonic cleaning post-drying treatment. In one embodiment of the invention, in the ultrasonic cleaning process, cleaning is sequentially performed in acetone, ethanol and deionized water for 20-40 min; in the drying