IMPROVING SURFACE ROUGHNESS BY ELECTRICAL DISCHARGE MACHINING WITH TUNGSTEN POWDER

Abstract

Electrical discharge machining (EDM) process is widely used to process hard materials in the industry. The process of electrical discharge is changed and called PMEDM when alloy powder is added in the oil dielectric. Studies show that the surface roughness (Ra) obtained by PMEDM is generally better than that by normal EDM. In the current study, the effect of tungsten carbide alloy powder added to the dielectric on the surface roughness status of the workpiece SKD61 after machining is investigated. The experiment shows that at the selected process window, adding the powder has resulted in an improvement of the surface roughness up to 57.98% as compared to the high surface roughness Ra of 0.471 μm by normal EDM.