Chemical Properties Of Tungsten Crucible

Oct 31, 2019

Tungsten crucible is one of the metal tungsten products, mainly divided into sintering forming (applied to powder metallurgy technology), stamping forming, spinning type. Tungsten bar turning processing molding (general size is relatively small), welding forming a variety of pure tungsten plate, tungsten sheet and pure tungsten bar through the corresponding process of processing. Tungsten crucible can be used in vacuum inert gases up to 2600 degrees. Tungsten melting point boiling point, high temperature strength, corrosion resistance, high heat conductivity, small coefficient of thermal expansion, hardenability.

Tungsten crucible is widely used in rare earth smelting, quartz glass, electronic spray, such as crystal growth industry. Tungsten crucible chemical properties of tungsten is rare high melting point metal, and can improve the high temperature hardness of steel, belongs to the periodic table 6 cycles Ⅵ group B (2) for a long period of time. Tungsten is a silver-white metal, shaped like steel. Tungsten has a high melting point, a low vapor pressure, and a low evaporation rate. Tungsten chemical property is very stable, normal temperature does not react with air and water, not heating, any concentration of hydrochloric acid, sulfuric acid, nitric acid, hydrofluoric acid and wang shui do not have an effect on tungsten, when the temperature rises to 80° -- 100°C, above all kinds of acid, except hydrofluoric acid, other acid weak effect on tungsten. At room temperature, tungsten can be quickly dissolved in a mixture of hydrofluoric acid and concentrated nitric acid, but not in alkaline solution.

In the presence of air, the molten alkali can oxidize tungsten to tungstate, which reacts more violently in the presence of oxidants (NaNO3, NaNO2, KClO3, PbO2). It can be combined with chlorine, bromine, iodine, carbon, nitrogen and sulfur at high temperature, but not hydrogenated.