The role of coatings in controlling the cutting process when turning with coated indexable inserts

This paper is concerned with the variations in the specific cutting pressure and the tool-chip interface temperature that occur when machining a medium carbon steel and an austenitic stainless steel with TiC-, TiC/TiN- and TiC/Al2O3/TiN- coated inserts. Extensive experimental studies involving the cutting force and the interface temperature were performed. A standard thermocouple embedded in the workpiece was used to determine the cutting temperature. Two new parameters were introduced in order to compare both the mechanical and thermal loadings of the tool-chip contact for coated flat-faced and grooved inserts. Some optimal coating structures for high speed machining of these steels corresponding to the minimum interface temperature and power consumption were selected. This new methodology for assessing both mechanical and thermal loads of the primary land in comparison to the natural tool-chip contact provides comprehensive data for designing coated grooved inserts. (C) 1998 Elsevier Science S.A. All rights reserved.