Increasing productivity in hard turning of steels using CVD-coated carbide

Abstract

Productivity is the essence of hard machining concept. Many aspects studied in hard machining but still were not dealing directly with productivity. In this study, the strategy dealing with an effort to increase productivity in cutting of hardened steel by utilising a triple-layer TiN/Al2O3/TiCN CVD-coated carbide tool has been developed. The selection of cutting condition, tool life criteria, cutting tool performance, and the quality of surface finish are considered in order to define the productivity parameters material removal rate (MRR) and volume of material removal (VMR). The study shows that the highest VMR of 1,050 cm3 when cutting AISI 1045 (42±1 HRC) and 433.88 cm3 for AISI 4340 (48±1 HRC) are achieved at flank wear (VB) 0.2 mm and surface finish (Ra) at smooth quality (N7-N8). The study also concludes that better tribological behaviour of coating layer(s) provides longer tool life, better surface quality, and higher productivity.