Tungsten Oxide

The performance of tungsten oxide materials will directly affect the reduction behavior of tungsten powder and the final product performance. Therefore, on which material is most suitable for the production of ultrafine tungsten powder has been the subject of much attention in material science workers. Blue tungsten oxide and purple tungsten oxide is the main raw material for production of ultrafine tungsten powder, blue tungsten oxide originated in the last century 70's, mainly WO 2.90 , W 20 O 58  and ammonium tungsten bronze (ATB) mixture. Purple Tungsten oxide is a kind of tungsten oxide product developed in recent years in China. Its phase composition is WO 2.72  or W 18 O 49 . Blue tungsten is present through hydrogen reduction of raw materials prepared by tungsten powder is the most widely used, as long as the conditions of low temperature, dry hydrogen, high hydrogen flow, thin material layer, producing ultrafine tungsten powder method can restore t...

The performance of tungsten oxide materials will directly affect the reduction behavior of tungsten powder and the final product performance. Therefore, on which material is most suitable for the production of ultrafine tungsten powder has been the subject of much attention in material science workers. Blue tungsten oxide and purple tungsten oxide is the main raw material for production of ultrafine tungsten powder, blue tungsten oxide originated in the last century 70's, mainly WO 2.90 , W 20 O 58  and ammonium tungsten bronze (ATB) mixture. Purple Tungsten oxide is a kind of tungsten oxide product developed in recent years in China. Its phase composition is WO 2.72  or W 18 O 49 . Blue tungsten oxide is present through hydrogen reduction of raw materials prepared by tungsten powder is the most widely used, as long as the conditions of low temperature, dry hydrogen, high hydrogen flow, thin material layer, producing ultrafine tungsten powder method can ...

Purple tungsten oxide using the APT as raw materials,which is during at the closed furnace in the industry. Under certain conditions, adding NH3 during calcination, and the NH3 will decompose H2 and N2, it will form a wet hydrogen atmosphere furnace in the stove, so that APT under mild reducing atmosphere, gradually decompose, generating purple oxide reduction. There are many factors in the process of preparing purple tungsten, one by the hydrogen reduction of tungsten oxide mechanisms apparent hydrogen greater humidity, the temperature required to obtain the higher tungsten purple, so choose the calcination temperature should be 770 ~ 815 ℃, Second, in the calcination process feed speed, tube speed, NH3 traffic and others factors affect the production of tungsten purple in varying degrees. In the preparation of tungsten purple we should to coordinate various relationships in order to produce a single phase purple tungsten. Its chemical equations are: 3 [5 (NH4) 2O · 12WO3 · 5H2O] = ...