EFFECT OF ANNEALING ON MACHINABILITY OF GREY CAST IRON

Abstract

This study investigates the influence of process parameter on machined cast iron under varying material strength and cutting conditions. The three process parameters considered in this study are spindle speed (75-135 rpm), feed rate (0.05-0.4 mm/min) and depth of cut (0.01-0.08 mm). The cast iron bars wereannealed and machined under wet and dry cutting conditions. Taguchi design of Minitab 18 was employed to optimize and analyze results. The signal-to-noise (S/N) ratio was used to analyze results generated, identify optimal process parameters (factors) and analyze the effect of these parameters on tool-tip temperature. Results shows that the spindle speed was the most significant factor affecting tool-tip temperature reduction, followed by feed rate, while the depth of cut has least role to play on tool-tip temperature. Depth of cut and spindle speed both significantly influenced increment in material removal rate. The annealed cast iron bar had a better surface integrity than the unannealed sample bars. Conclusively, the preferred condition for machining grey cast iron bar was annealed and wet machining condition.