Characterization of machining of AISI 1045 steel over a wide range of cutting speeds. Part 1: investigation of contact phenomena

Friction conditions at the tool-chip interface are one of the most important inputs for modelling and simulation of the machining process. However, the nature of the tool-chip contact is often assumed in developing finite element models, thereby seriously affecting their reliability. In this paper, results of an investigation into the tool-chip contact interface using uncoated tungsten-based cemented carbide tools in dry high-speed turning of AISI 1045 steel are presented. The tests were conducted at cutting speeds ranging between 198 and 879 m/min with a feed rate of 0.1 mm/rev and a constant depth of cut of 2.5 mm. The effects of cutting speed on tool rake face contact length, contact area, friction, element mapping, and surface roughness are studied and discussed. It is shown that the quantitative methods, used here to characterize the tool-chip contact region, can provide valuable data for accurate and reliable modelling of the metal machining process over a wide range of cutting speeds.