Optimization of Machining Parameters in Hard Turning Process Using Taguchi Orthogonal Array

Hard turning is one of the key process in advanced machining technology for machining of hardened steels such as tool steel, titanium, nickel alloy, Inconel etc. Hard turning process has various benefits such as increase productivity, achieve mirrorsurface finish, reduce machining time, reduction of processing costs, and improve material properties. This paper focused on optimizing of surface roughness and cutting forces in hard turning of AISI S7 tool steel using Taguchi method. The main objective of experiment was correlation between cutting parameters such as cutting environment, cutting speed, feed rate, depth of cut with surface roughness and cutting force. Four cutting parameters such as cutting environment, cutting speed, feed rate, and depth of cut, each at three levels except the cutting environment at two levels were considered. Taguchi L₁₈ orthogonal array was used as design of experiment. The S/N ratio, analysis of variance (ANOVA), main effect plots, interaction plots, and residual plots are used to find the optimal level and to analyze the effects of process parameters on surface roughness and cutting forces. The result showed that the feed rate and cutting speed are significantly affects on surface roughness; the depth of cut is significantly affects on cutting forces. The range for optimal cutting condition is proposed for various production industries.