LOW-TEMPERATURE CHEMICAL-VAPOR-DEPOSITION OF DIAMOND ON TUNGSTEN CARBIDES USING CF4 GAS DOPING FOR MACHINE-TOOL APPLICATIONS

We report here the improvement of the adhesion of CVD diamond films on WC- Co (6%) tools and the enhancement in the cutting tool life- time by the introduction of CF4 in the CH4/H-2 gas mixture. By the use of t his halogen precursor it was possible to reduce the substrate temperat ure during the deposition without degradation in the diamond film qual ity. The low-temperature deposition improves the smoothness of the coa ting and minimizes the thermal stress induced by the CVD process.