Tool rake face temperature distribution by near infrared thermography

Abstract

This thesis is concerned with experimentally obtained full field temperature distributions at the interface between chip and tool - the tool rake face - for the machining of Ti6Al4V and Inconel 718. As part of the work presented herein, temperature distributions at the chip-tool interface were obtained using a novel technique, near infrared thermography, which provides high accuracy for the target temperature range above 1250 K. During the study, transparent yttrium aluminum garnet (YAG) tools were used to provide an optical path to the chip-tool interface. The YAG tool wear behavior was characterized using optical profilometry. Additionally, the YAG tools were coated with a nanometric layer of an anti-friction material, titanium nitride (TiN). The performance of the coated tool was evaluated in terms of temperature and wear characteristics. Modeling was performed to justify the methodology adopted to infer chip-tool temperature distribution from the temperature directly measured at the interface between the TiN coating and the YAG tool.