Effect of cutting speed on the performance of Al2O3 based ceramic tools in turning nodular cast iron

This paper presents the results of an experimental investigation on the effect of cutting speed in turning nodular cast iron with alumina (Al2O3) based ceramic tools. Three different alumina based ceramic cutting tools were used, namely TiN coated Al2O3 + TiCN mixed ceramic, SiC whisker reinforced Al2O3 and uncoated Al2O3 + TiCN mixed ceramic tool. Turning experiments were carried out at four different cutting speeds, which were 300, 450, 600 and 750 m/min. Depth of cut and feed rate were kept constant at 1 mm and 0.1 mm/rev, respectively, throughout the experiments. Tool performance was evaluated with respect to tool wear, surface finish produced and cutting forces generated during turning. Uncoated Al2O3 + TiCN mixed ceramic was the worst performing tool with respect to tool wear and was the best with respect to surface finish. SiC whisker reinforced Al2O3 exhibited the worst performance with respect to cutting forces. If tool wear, surface finish and cutting force results are considered together, among the three tools studied, TiN coated Al2O3 + TiCN mixed ceramic tool is the most suitable one for turning nodular cast iron, especially at high cutting speeds (Vc > 600 m/min).