Cryogenic Hard Turning of Alloy Steel with Multilayer Hard Surface Coatings (TiN/TiCN/Al O /TiN) insert using RSM. 2 3

Abstract

This paper investigates the effect of different cutting parameters (cutting speed, feed rate, and depth of cut) on cutting forces in cryogenic hard turning processes. The workpiece material, hardened alloy steel AISI 52100, was machined on a CNC lathe with multilayer hard surface coatings (TiN/TiCN/Al O /TiN) insert under different settings of cutting 2 3 parameters. Three cutting parameters each at three levels were considered in the study. Central composite design (CCD) of experiment was used to collect experimental data for cutting forces. The results were analyzed using an effective procedure of response surface methodology (RSM) to determine optimal values of cutting parameters. Statistical analysis of variance (ANOVA) was performed to determine significance of the cutting parameters. The results indicated that cutting forces are influenced principally by the cutting speed, feed rate and depth of cut. The ranges for best cutting parameters and model equations to predict the cutting forces were proposed. Confirmation experiments were performed to verify the pertinence of the developed empirical models. Finally, the optimum machining conditions to produce the minimum cutting forces under these experimental conditions were searched using desirability function approach for response factors optimization