Tungsten coils

Tungsten is a very hard, steel gray metal. Its melting point is the highest in pure metals, up to 3415 °C. Pure tungsten is very brittle, difficult to process. It should be softened by high temperature before processed by forging, stretching or impact.    
Tungsten is widely used in applications such as electro-optical materials, special alloys, medical technology, energy materials and even arms industry. Even if the amount is not large, it still plays an extremely important position. Tungsten is a rare metal, 70% of its output comes from China. Its price will fluctuate due to market monopolies, and may even adjust prices once a week. 
 

The tungsten coils used for headlights coating are similar to the evaporation boats—they both are the carrier for coating materials. The operation method is to insert pieces of aluminum coils onto tungsten filaments. The filaments are connected to electrical feedthroughs. When sufficient current is applied, the aluminum instantaneously (flash) evaporates. 
 

Although the tungsten coils can be reused during the coating process, they might contaminate by the residual aluminum after using for a period of time. That will cause the tungsten coils to be easily broken and need to be replaced. 

Sunda Optical Material offers different specifications of tungsten coils which can perfectly suit your needs.