An alloy produced by exposing tungsten, heated to high temperatures, to carbon monoxide or other hydro-carbon gases. Tungsten carbide is almost as hard as the diamond, registering between 9 and 10 on the Mohs Scale. It is crushed and graded into various sizes; it is furnished in irregular fragments for hardfacing, and is also molded into shapes to be used in place of black diamonds in cutting tools.
A number of welding rods and electrodes are made to deposit small particles of this very hard alloy on the cutting faces of tools, bits, and other parts on which it is embedded in a matrix of softer welded deposit. There are several methods for accomplishing this purpose by using various types of rods. See HARDFACING.