Regeneration of the WC-Co Hard Alloy with the Use of Gaseous Zinc

The technology of regeneration of the WC-Co hard alloy by gaseous zinc is developed. It is shown that the diffusion of Zn in the alloy proceeds mainly along phase boundaries between tungsten carbide and cobalt with a high rate comparable to that during the diffusion of Zn in aqueous solutions. The new technology provides a substantial decrease in the power consumption owing to a decrease in the duration of operations compared with the classic zinc process. The experimental values of the activation energy of the diffusion of Zn in the hard alloy and cobalt are found to be 1.74 and 13.97 kJ/mol, respectively.