The tungsten switch contact is made of metal tungsten, which has good heat resistance, lower resistance, good chemical stability and other advantages, and can be very good circuit connection or break, thereby reducing the probability of electrical equipment failure.

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.

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.