Tungsten Silicide
Introduction
Name: Tungsten Silicide
CAS: 12039-88-2
Formula: Si2W
Molecular weight: 240.01100
Exact Mass：239.90500
Density: 9.88 g/cm3
Melting Point: 900ºC
Property
Appearance: blue-gray tetragonal crystal, odorless
Tungsten silicide insoluble in water and aqua regia, but can be dissolved in a mixture of nitric and hydrofluoric acid, which can be used for antioxidant cover layer and resistance wire poultice.
Preparation
(1) Formulate the tungsten and silicon powder, titanium and graphite powder respectively at the molar ratio of 1:2, 1: 1, and then mixed uniformly;
(2) Place the W-Si mixed powder in the center of crucible, Ti-C mixed powder uniformly disposed between W-Si mixed powder and the crucible, Ti-C mixed powder layer is installed at the top of all the mixed powder, the weight ratio of W-Si and Ti-C mixed powder is (0.8~1.2): 1;
(3) Loading the crucible with mixed powder in a sealed reactor, tungsten wire energized to initiate the reaction of the mixture after evacuated and filled with argon gas;
(4) Remove the products and cool down, separate titanium carbide and tungsten disilicide and crushing respectively to obtain titanium carbide and tungsten disilicide powder.