Optimization of Turning Process Parameters in Machining of Heat-Treated Ductile Iron Bar Using TiC/TiCN/Al₂O₃-Coated Tungsten Carbide Tool

Abstract

The main aim of this study is to find the optimum turning parameters on the machining of heat-treated ductile iron bar using TiC/TiCN/Al₂O₃-coated tungsten carbide insert as tool. The ductile iron bar is heat treated, and a three-layer coating is done on the tungsten carbide insert using chemical vapour deposition (CVD) method. Taguchi method is used to find the optimum turning parameters for material removal rate (MRR) and surface roughness. Process parameters such as cutting speed (500–1200 rpm), depth of cut (0.051–0.159 mm) and feed rate (0.5–1 mm/min) were analysed by Taguchi L9 orthogonal array table. The effect of turning parameters on material removal rate (MRR) and surface roughness was analysed by signal-to-noise ratio(S/N) and analysis of variance (ANOVA). The result shows that material removal rate (MRR) and surface roughness were highly influenced by cutting speed followed by depth of cut and feed rate. Regression equation was developed and was validated by confirmatory experiments.