Purity of Tungsten Powder

Purity of the tungsten powder is of particular importance in powder metallurgy manufacturing of tungsten metal and alloy, since the purity of subsequent products are mainly influenced by raw materials. Typical upper limits of foreign element concentrations by chinese national standard(GB) in µg/g are follow:

IMPURITIES OF TUNGSTEN POWDER

Since the remaining impurities after sintering significantly influencing the workability (grain boundary strenth, recrystallization temperature, grain size,etc.) and properties of the product, the impurities concentrations are strictly limitted in low level.

The purity of tungsten powder is mainly determined by the APT cleaness, since  the maximum purity at the stage of APT crystallization in production process is more or less reached. Sources of contaminations after APT processing

mainly contacts with metallic tubes or boats in the furnaces. Consequently the foreign elements such as Fe, Ni, Cr and Co, are slightly increasing.

 

 

微信公众号

タングステン知識

タングステン知識

 

絶縁ガラス用Cs 0.32 WO 3粒子

絶縁ガラス用Cs 0.32 WO 3粒子