Purification Of Refractory Metals

Jan 06, 2020

The existence of a large number of impurities in refractory metals greatly affects and determines the properties of materials, which severely restricts the development of science and technology and the engineering applications of materials.

The unique and excellent mechanical properties and physical properties of high-purity refractory metals make it a strategic metal material that is increasingly valued by countries around the world. The increasing demand for high-purity refractory metals by modern science and technology and basic theoretical research makes the purification of refractory metals of great significance.

1) Both electron beam region melting method and plasma arc melting method can effectively realize the purification of refractory metals and the growth of single crystal materials. The concentration of most impurity elements can be reduced by 2 to 4 orders of magnitude, and the gas impurity elements C, N, and O can be removed most thoroughly.

2) Improve the vacuum of the equipment workshop(Such as 10^-6~10^-8P orders of magnitude)Utilizing a controllable atmosphere (such as rationally controlling the gas components that generate plasma), using a vacuum system without oil pumps, introducing turbo molecular pumps, sputtering ion pumps, etc., using higher (energy) density heat sources such as light sources, continuous (laser) ) Or non-continuous energy sources (arc lamps, incandescent lamps, solar energy), the establishment of automatic control and feedback adjustment systems for electron beam or plasma arc heating power, temperature gradient and crystal interface shape control systems, plasma gun scanning systems, etc. Computer automatic control program systems are ideal for the purification of refractory metals and the growth of single crystals.

3) Combining the advantages of various purification methods, such as combining the electron beam region melting method, plasma arc melting method and other purification methods under certain process conditions, the deep purification of refractory metals is achieved more thoroughly.