Thermocouple and Infrared Sensor-Based Measurement of Temperature Distribution in Metal Cutting

TLDR

In metal cutting, tool‑chip interface temperature depends on cutting parameters and influences production, motivating research to improve machining operations. The study aimed to estimate tool temperature by simultaneously measuring it with a K‑type thermocouple and an infrared pyrometer. Tool temperature was measured in dry turning of heat‑treated AISI 4140 steel using a PVD TiAlN‑TiN coated carbide insert, with data from a thermocouple and IR pyrometer compared against ANSYS finite‑element simulations. Results showed that increasing cutting speed, feed rate, and depth of cut raised tool temperature, with cutting speed having the greatest effect, and the heat‑distribution data can guide optimization of orthogonal machining parameters.

Abstract

In metal cutting, the magnitude of the temperature at the tool-chip interface is a function of the cutting parameters. This temperature directly affects production; therefore, increased research on the role of cutting temperatures can lead to improved machining operations. In this study, tool temperature was estimated by simultaneous temperature measurement employing both a K-type thermocouple and an infrared radiation (IR) pyrometer to measure the tool-chip interface temperature. Due to the complexity of the machining processes, the integration of different measuring techniques was necessary in order to obtain consistent temperature data. The thermal analysis results were compared via the ANSYS finite element method. Experiments were carried out in dry machining using workpiece material of AISI 4140 alloy steel that was heat treated by an induction process to a hardness of 50 HRC. A PVD TiAlN-TiN-coated WNVG 080404-IC907 carbide insert was used during the turning process. The results showed that with increasing cutting speed, feed rate and depth of cut, the tool temperature increased; the cutting speed was found to be the most effective parameter in assessing the temperature rise. The heat distribution of the cutting tool, tool-chip interface and workpiece provided effective and useful data for the optimization of selected cutting parameters during orthogonal machining.