ANALYSIS OF TOOL MATERIAL ON METAL REMOVAL RATE IN ELECTRICAL DISCHARGE MACHINING

Abstract

H11 tool steel is an exceptional class of alloy steel, also known as chromium tool steel. It found applications in forging and extrusion dies, helicopter rotor blades etc. Electrical discharge machining (EDM) is one of the alternative processes to shape this material. This study exhibits the effect of discharge current (Id) and gap voltage (Vg) on metal removal rate (MRR) during EDM of H11 tool steel by taking three different tool electrode materials. Experiments have been performed by varying Id in four steps (4 A, 8A, 12 A, 16 A) and Vg in (25 V, 30 V, 35 V, 40 V) while keeping the values of other variable fixed. On the basis of experimental findings, it is concluded that tool properties of the electrode play a crucial role in machining characteristics of EDM process. The results show that graphite electrode offers the higher MRR followed by aluminium and copper electrode in EDM of H11 tool steel.