A Study on Dry Electrical Discharge Machining Process

This study investigates the characteristics of the dry electrical discharge machining (EDM) process. Dry wire EDM experiments of thin workpieces were conducted in air, which was used as the dielectric fluid. The relationships among spark cycle (T), spark on-time (T
on
), air flow, thickness of workpieces and work material were studied in the cases of wet and dry EDM conditions. The material removal rate (MRR), in general, in dry EDM was much lower than that in wet EDM, and the effects of various EDM parameters on MRR were comparatively investigated in the cases of dry and wet wire EDM processes. The thickness of workpiece and work-material were critical ones to influence on the MRR. Die-sinking dry EDM process was also investigated by developing the miniaturized desktop dry EDM machine tool. The aluminum workpiece was dry-EDMed with the copper tubular electrode under the conditions of no air, air blowing and suction, and the machined results were compared.