HIGH TEMPERATURE REACTION BETWEEN WC TOOLS AND FERROUS METALS.

Interdiffusion in cobalt bonded WC tool-workpiece system in the temperature range 1100 degree -1300 degree C has been studied with special emphasis on the effects of cobalt and carbon contents in tool and workpiece respectively. Techniques employed for analyzing the obtained diffusion layers are electron probe microanalysis, microscopy and microhardness measurement. It is shown that for the tool-low carbon steel system, carbon in the tool diffuses into the workpiece resulting in the formation of M//6C-type carbide layer, but that no carbon migration occurs for tool-cast iron system. A tentative mechanism of the interdiffusion has been proposed based on the experimental results.