1. Nano Tungstic Acid
Nano tungstic acid has a large specific surface area and significant surface effect. 

Tungsten heater is used in vacuum coating furnace, which is widely used to coat the surface of bottle lid.

1. Overall Review of Tungsten Trioxide Produced by Extraction Method 

2. The main production process is using tungsten scheelite as raw material: roasting, grinding, alkaline pressure cooking to prepare sodium tungstate solution, purification and impurity removal, filtration of solid-liquid separation, sulfurization, acid adjustment filtration, extraction and back extraction, the ammonium tungstate solution is evaporated and crystallized, dried and sieved to obtain ammonium paratungstate (APT) product. After calcining APT, tungsten trioxide is obtained.

Tungsten alloy application in military industry is mainly for aerospace, weapon and nuclear industry. Tungsten alloy (WHA) is heavy metal with main content of tungsten 90~97%, and other elements, such as copper, nickel, iron, manganese, and molybdenum.