The use of SiC powder in water as dielectric for micro-slit EDM machining

Green manufacturing technology has recently become very important to all manufacturing industries. Pure water and the SiC powder produce a good post-process treatment without any environmental pollution. Micro-slit EDM process along with small discharge energy and SiC powder in pure water was investigated in this study. SiC powder was added to pure water as a working fluid to verify the micro-slit EDM process performance. Results indicated that the addition of SiC powder would increase working fluid electrical conductivity, enlarge the electrode and workpiece gap, and also extrude debris easily, therefore increasing the material removal rate. Furthermore, the use of SiC powder helped bridge the electrode and workpiece gap and disperse discharge energy, thus creating two discrete discharging pulses from a single discharging period that could effectively disperse discharging energy into several increments. The discharging results could then generate a minor crater and debris since minor debris would ease gap exhaust and accelerate material removal rate. The minor crater could simultaneously refine the surface roughness.