NbMoTaW high-entropy alloy, and preparation method thereof

Abstract

The invention belongs to the technical field of high-entropy alloy, and discloses a NbMoTaW high-entropy alloy, and a preparation method thereof. According to the preparation method, mechanical alloying and spark plasma sintering are combined for forming, alloying of Nb, Mo, Ta, and W which are high in melting points is realized at solid states, heating to the melting points is not necessary, block materials with excellent performance can be obtained via only one time of solid phase sintering ( the sintering temperature is 1600 DEG C or lower), a difficult problem that the melting temperature (>2900 DEG C) of smelting method is high is solved, processing temperature is reduced greatly, and technology is simplified. According to the microscopic structure of the NbMoTaW high-entropy alloy, dispersion distribution of a granular second phase in an isometric crystal substrate is observed, both the substrate phase and the second phase are BCC solid solution, the substrate average particle size is smaller than 6<mu>m, the second phase average particle size is smaller than 4<mu>m, the material crystal particles are small, the structure is uniform, no dendritic segregation is caused, and strength and hardness are high.

Description

technical field [0001] The invention belongs to the technical field of high-entropy alloys, in particular to a NbMoTaW high-entropy alloy and a preparation method thereof. Background technique [0002] High entropy alloy is a new type of alloy developed in recent years. Unlike traditional alloys that use one or two elements as the main components, high-entropy alloys contain multiple main components, which are generally defined as alloying of five or more elements in an equiatomic ratio or close to an equiatomic ratio Alloys, generalized high-entropy alloys often include alloys with four or three principal elements. Because this type of alloy has a high mixing entropy, it tends to form a high-entropy solid solution with a single-phase or multi-phase simple structure, rather than a complex structure such as an intermetallic compound. The existing research results show that high-entropy alloys have some properties superior to traditional alloys, such as: high strength, high ...

AI Technical Summary

Problems solved by technology

However, the problems of this method are: electrode pollution, poor arc stability, slow melting speed, low efficiency, difficult to control the proportion of alloy components, easy to produce component segregation, etc.

In order to make the elements in the alloy evenly distributed, the alloy ingot needs to be smelted several times, the process is complicated and the energy consumption is high