High Bandwidth Thermal Microscopy of Machining AISI 1045 Steel

A custom thermal microscope was constructed using a high-bandwidth thermal imaging system (40 megapixels/sec). The microscope was attached to a high-speed machining centre (20 thousand RPM/18.5 kW spindle) that was operated as a high-speed lathe to measure temperature distributions during orthogonal cutting of AISI 1045 steel at surface speeds of up to 605 m/min. Measurements were made for a wide range of cutting parameters and compared with finite element analysis. While the ultimate goal is to produce improved tool design, the results emphasize the need for predictive rather than interpretive simulation of the temperature fields in machining.