Chemical properties of tungsten crucible
Tungsten crucible is one of the metal tungsten products, mainly divided into sintering molding (applied to powder metallurgy technology), stamping molding, spinning type. The use of tungsten rod turning forming (general size is relatively small), welding forming a variety of, the use of pure tungsten plate, tungsten and pure tungsten rod by the corresponding process. Tungsten crucible can be used in vacuum inert gases up to 2600 degrees. Tungsten has high melting and boiling point, high temperature strength, abrasion resistance and corrosion resistance, large thermal conductivity, small thermal expansion coefficient and good hardenability. Tungsten crucible is widely used in rare earth smelting, quartz glass, electronic spraying, crystal growth and other industries.
Chemical properties of tungsten crucible;
Tungsten is a rare metal with high melting point, which can improve the high temperature hardness of steel. It belongs to group ⅵ B of the sixth period (long period) in the periodic table of elements. Tungsten is a silver-white metal that looks like steel. Tungsten has a high melting point, low vapor pressure and low evaporation rate. The chemical properties of tungsten are very stable, at room temperature does not react with air and water, not heated, any concentration of hydrochloric acid, sulfuric acid, nitric acid, hydrofluoric acid and aqua regia have no effect on tungsten, when the temperature rises to 80° -100 °C, the above various acids, in addition to hydrofluoric acid, other acids have weak effect on tungsten. Tungsten dissolves rapidly in a mixture of hydrofluoric and concentrated nitric acids at room temperature, but does not act in alkaline solutions. In the presence of air, molten base can oxidize tungsten to tungstate, and in the presence of oxidants (NaNO3, NaNO2, KClO3, PbO2), the reaction to generate tungstate is more violent.
