Comparative Assessment on Machinability Aspects of AISI 4340 Alloy Steel Using Uncoated Carbide and Coated Cermet Inserts During Hard Turning

This paper compares the performances of uncoated carbide and coated cermet inserts for varied machinability aspects throughout the machining of hardened steel (AISI 4340, 48 HRC) in the dry cutting surroundings. Cutting speed, feed, and depth of cut were thought of as major governing parameters. Workpiece surface temperature, machining forces, and tool flank wear were taken as measures to check the performance estimation of various cutting inserts during this work. All the three input variables were ascertained to possess influence over workpiece surface temperature, feed, and radial force in case of uncoated carbide and cermet. Cermets exceeded the performance of carbides for flank wear, cutting force, and workpiece surface temperature, although carbides outperformed cermets concerning feed and radial force. The depth of cut was found to be the most vital, once feed and cutting forces were involved, whereas it had been true for radial force using carbides. Cutting speed affected workpiece surface temperature and flank wear for carbides the most; in the meantime, this was the same once considering the radial force with cermets. The feed was the foremost vital parameter, while the flank wear of cermets was taken into account. ANOVA, regression analysis, and main effect plots were accomplished using the MINITAB-16 software.