Tungsten alloy is an alloy composed of tungsten as the base and other elements. It is a metal material with tungsten powder as the main raw material and nickel, iron, copper and other elements as auxiliary materials. It is a dense, ductile, and high-temperature corrosion resistant material.
Among metals, tungsten has the highest melting point, good high-temperature strength, creep resistance, thermal conductivity, conductivity, and electron emission characteristics, as well as a large specific gravity. In addition to a large amount of hard alloys and alloy additives, tungsten and its alloys are widely used in the electronic and electric light source industries, as well as in sectors such as aerospace, casting, and weapons. They are used in the manufacturing of rocket nozzles, die-casting molds, armor piercing bullet cores, contacts, heating elements, and heat shields.
The production of doped tungsten alloy usually uses Ammonium paratungstate as raw material. In addition to the traditional classical process, the international research has also carried out the extraction method and ion exchange method of preparing Ammonium paratungstate from tungsten concentrate. China has also adopted these processes, thereby simplifying the process flow and improving the recovery rate of tungsten. Many countries have adopted the blue tungsten oxide doping process to replace the Tungsten trioxide doping, thus improving the doping effect.
Qualified billets are one of the key factors in the production of tungsten materials, and the first step in preparing billets is to select qualified tungsten powder. The characteristics, mixing, forming, and sintering processes of powder directly affect the composition, density, and microstructure of the billet, and strongly affect the processing and usage performance of the product. Silicon, aluminum and potassium elements added in non sagging tungsten wire are added in the form of Tungsten trioxide or oxide in "blue tungsten". The mixture is often washed with hydrofluoric acid solution to remove impurities in the powder. The billets for producing silk and small sheets are mostly formed on a press, and can also be formed by isostatic pressing.
