粉末混入放電加工法を用いた表面改質

抄録

In this study, EDM with a powder suspended dielectric has been applied in order to improve the surface quality of workpieces. WC (tungsten carbide) as a suspended powder and DC53 (die steel for cold working) as workpieces were both adopted. Just after the WC powder was suspended into the dielectric, the surface of the workpiece was not modified but machined. As the discharge time for modification was accumulated, the surface became modified. After confirming that the surface was modified with the WC powder suspended dielectric, the effects of the discharge time per treatment on the characteristics of the modified layers were investigated. The longer the discharge time per treatment was, the harder the surface of the improved layer became. This is due to the increase of the produced amount of WC_1-x. Ohgoshi wearing-out test was performed to evaluate the wear resistance of the improved layers. It revealed that the worn volume of the improved layer was decreased maximally by about 10% as compared to that of the base steel.