Surface treatment of fine grain cemented carbide by large-area electron beam irradiation

Cemented carbide has many excellent properties like high strength, high hardness and high wear-resistance. However, it is often difficult to apply conventional surface finishing or surface modification methods because of its excellent mechanical properties. The purpose of this research is to improve the surface characteristics of cemented carbide by large-area electron beam irradiation. The possibilities of surface smoothing and surface modification were discussed with varying the energy density of electron beam and the number of pulse. The following results were obtained from the experimental analysis. The frequency of surface roughness of surface irradiated by large-area electron beam became lower, and glossiness was higher than those of initial surface. The contact angle of water on electron beam irradiated surface was higher than that on initial surface, which means that the surface has high water repellency. Oil extension area investigated for evaluating lipophilicity was smaller than that of initial surface. The separation force of molded resin measured for releasability evaluation could be reduced by large-area electron beam irradiation. From these experimental results, it was made clear that the surface characteristics of cemented carbide can be improved by large-area electron beam irradiation.