Study on cutting performance of cermet tool in turning of hardened alloy steel

Abstract

The intention on finding the alternative tool material to support the usage of Coated Cemented Carbide for increasing the productivity in turning of hardened steel is the rationality of this study. Study on the mechanical properties of hardmetals and the advantages of modern Cermet cutting tools lead to nominate this tool to be applied for turning of hardened steel. The Uncoated Cermet tool made of titanium carbonitride (TiCN) as core particles, (Ti, Nb, W) (C, N) for the second hard phase, and a W-rich Co binder and the PVD-Coated (TiCN/TiN) were assigned to turning of high strength low alloy AISI 4340 with hardness of 50 HRC. The results of study show that both Cermet tools can be recommended to support the work of Coated Cemented Carbide, in particular for finish turning of the hardened steel. The optimum cutting condition at cutting speed (v) of 120 m/min, feed (f) of 0.1 mm/rev, and depth of cut (a) of 0.2 mm gives the best result in term of productivity. The Uncoated Cermet is preferred when productivity (Q) is in the amount of material removal (Q 81.60 cm3 per cutting edge at Ra 1.773 μm), while the PVD-Coated Cermet is the choice when productivity is more on quality of surface finish (Ra 0.891 μm) but the amount of material removal (Q 43.20 cm3 per cutting edge) is still concerned. Among those Cermet cutting tools reviewed, both Cermet cutting tools in this study are superior and worthy.