Effect of process parameters in the machining of Titanium alloy and high speed steel in powder mixed electrical discharge machining process

Abstract

Weight reduction is an everlasting challenge in automobile industry, which obviously results in CO2 emission and fuel economy in the vehicles. The quest drives the automobile industry to introduce Titanium in the car engines during 1990s. Among the newer materials used in the vehicle engine, Titanium have been traditionally used due to its strength-weight ratio, corrosion resistant, aesthetic surface appearance and luxurious feeling. But, it poses a stiff challenge in conventional machining due to its hardness and chemical reactivity at elevated temperature. HSS, extensively used in making cutting tool, is equally poses a challenge in its machinability due to its higher hardness. To machine such hardest materials like Titanium and HSS, Powder Mixed Electrical Discharge Machine (PMEDM) can be used. In this study, the EDM process parameters such as current, duty factor and concentration of the Alumina powder mixed dielectric were considered as input parameters and material removal rate (MRR) and tool wear index (TWI) were taken as responses. Taguchi’s L9 orthogonal array was used to optimise the process parameters and main effect plots was used to find the effect of various process parameters on MRR and TWI.