Tungsten silicide is an odorless blue-gray tetragonal crystal that dissolves in a mixture of nitric acid and hydrofluoric acid. But, it is insoluble in water and aqua regia. Its CAS No. is 12039-88-2, and molecular formula is Si2W, molecular weight is 240.01100, the melting point is 900°C, and the density is 9.88g/cm3.
Tungsten silicide can be applied to produce anti-oxidation coating layer and the resistance wire poultice.
Producing Method
1. Mix W powder and Si powder under mole ratio 1:2, Ti powder and graphite powder under mole ratio 1:1, then stir it evenly.
2. Input W-Si powder in the middle of crucible and Ti-C powder between W-Si and crucible. Then, pour Ti-C mixed powder on the top.
3. Input the crucible into a sealed reactor, after vacuumizing, inflate with argon, and energize the W wire to bring up reaction.
4. After cooling down, seperate carbon titanium and tungsten silicide. Carbon titanium and tungsten silicide powder is obtained after crushing.
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