Tungsten metallurgy and recycling. Products and safety

The effect of tungsten on the properties of steel, suggested by R.E. Raspe (1785) and H.L. Duhamel du Monceau (1786), was put into practice by Jacob and Köller in 1855; but tungsten steels only really took off at the end of the 19th century. The first tungsten filaments for electric lamps did not appear until 1909 (W.D. Coolidge: General Electric Co.). After the development of high-speed steels in 1900 (Bethlehem Steel Co.), of WC-Co "cemented carbides" in 1927 (Krupp) and then of heavy metals (W-Ni-Fe(Cu) alloys) in 1935, the importance of tungsten outlets continued to grow. This development paralleled that of powder metallurgy, the only method of consolidating this refractory metal and its compounds.

WC tungsten carbide currently accounts for around 65% of the world's tungsten production. It is the basic material for "cemented carbides" (WC-Co cermets) with a wide range of applications: machining tools (cutting, drilling, milling) for metals, wood and plastics; drilling tools (mining, oil, public works, DIY, etc.); wear parts (materials and punches; cutting, forming and striking tools; anvils for diamond synthesis; pen balls; anti-slip studs, etc.).

Figure 1 is an overview of the tungsten industry and its main derivatives.

The complete study of the subject includes the articles :

• M 2 378 Tungsten metallurgy and recycling. Processes ;

• M 2 379 Tungsten metallurgy and recycling. Products and safety (this article) ;

• Doc. M 2 380 Metallurgy and recycling of tungsten.