Predictive modeling of surface roughness in high speed machining of AISI 4340 steel using yttria stabilized zirconia toughened alumina turning insert

An attempt has been made to investigate the surface finish of AISI 4340 steel for high speed machining using indigenously prepared yttria stabilized zirconia toughened alumina (ZTA) cutting inserts. These inserts are prepared through wet chemical co-precipitation route followed by powder metallurgy process. Response surface methodology (RSM) has been used to study the effect of different machining parameters i.e. cutting speed, feed rate and depth of cut on surface roughness of the job. The machining experiments are performed based on standard RSMdesign called central composite design (CCD). Themathematicalmodel of surface roughness has been developed using second order regression analysis. The adequacy of the developed models and influence of each operating factors have been carried out based on analysis of variance (ANOVA) techniques. It can be concluded from the present study that for high speed machining this tool gives good surface finish. Key parameters and their interactive effect on each response have also been presented in graphical contours which may help for choosing the operating parameter preciously. Optimization of cutting parameters has also been carried out and 92.3% desirability level has been achieved using this optimal condition