Experimental analysis and optimization of electrical discharge machining parameters with various shapes of tool electrodes and materials

Abstract

In recent times, demands for the high tech engineering ceramic newlinecomponents are increasing because of its excellent properties such as low newlinedensity, high hardness, high strength at high temperature, wear resistance, newlinethermal shock resistance. Ceramic components are widely used in various newlineapplications like heat exchangers, non-ferrous molten metal handling, gas newlineturbine components, wear-resistant components, aircraft engines, welding newlinenozzle, engine nozzle, and automobile parts. Hence, in this research work newlineSi3N4-TiN ceramic composite material has been selected as a work material. newlineOwing to the high hardness, of ceramics, conventional mechanical machining newlineis not viable and hence unconventional machining processes are widely used newlineby many researchers to machine the materials with high hardness. newlineIn this research work Electrical Discharge Machining (EDM) is newlineemployed and Pulse current, Pulse-on time, Pulse-off time, Method of EDM newline(rotary and sinking) and Tool shape are selected as highly influencing input newlineparameters among other factors. newlineThe objective of this research is, to maximize the MRR, minimize newlinethe over cut and taper ratio. Copper electrode is selected as tool electrode. newlineTaguchi L9 and L18 orthogonal array designs were used to conduct the newlineexperiments. newlineIn the EDM, various shapes of tool such as cylindrical, triangular, newlinesquare, rectangular, conical edge shape, taper edge shape, and helical tools newlinehave been employed by researchers for improving its performances. newlineHence, in this research, new shapes of tool electrodes such as newlinestepped diameter tool and cylindrical taper tool are employed as tool newlineelectrodes to increase material removal rate and to reduce overcut and taper newlineratio. newline