EFFECT OF POWDER MIXED DIELECTRIC ON MACHINING PERFORMANCE IN ELECTRIC DISCHARGE MACHINING (EDM)

ABSTRACT In this study, the variations of machining performance outputs, namely, workpiece surface roughness, workpiece removal rate, electrode wear rate, relative wear, workpiece surface hardness, and workpiece surface microstructure were experimentally investigated with the varying machining parameters for metal powder mixed dielectric liquid in electrical discharge machining (EDM). The machining tests were conducted by using prismatic steel workpiece and copper electrodes with graphite and boric acid powders (H 3 BO 3 ) mixed kerosene dielectric at different powder concentrations and pulse time settings. The experiments have shown that the type and concentration of the powders mixed into the dielectric and the pulse time were effective on machining performance outputs in EDM.