Formation of Chromium Carbide on Carbon Tool Steel by EDM in Powder Mixed Working Fluid

抄録

Formation of chromium carbide on the tool steel surface by EDM with chromium powder mixed fluid was examined in this study in order to discuss the applicability of inexpensive carbon tool steel SK105 to metal mold. Experimental results showed that the surface hardness, corrosion resistance, and releasability of molded resin from the surface were significantly improved by this method, since chromium carbide containing layer could be formed on the EDM finished surface. Moreover, hybrid powder mixed fluid EDM with chromium and silicon powders was proposed for further reduction in surface roughness. As a result, it was made clear that the formation of high functional EDM finished surface with smaller surface roughness was possible under optimum mixture ratio of chromium and silicon powders and EDM conditions.