Frictional Interactions between chip and rake face of PVD coated high speed steel cutting tools in relation with high temperature distribution in the tool and tool life

Tribological interactions in the vicinity of the cutting edge are always an interesting topic for researchers in the field of metal cutting. However, the role of frictional interactions between work and tool materials in determination of high temperature generated in the cutting tools leads to shorten tool life is not really understood. It is evident in this study that TiN-PVD coating layers on the rake face of high speed cutting tools using to machine medium carbon steels change the nature of frictional interactions between chip and rake face of the tool causing a reduction of contact length and an increase of shear angle (Ф). This affects directly on high temperature distribution in the tool, particularly sharper temperature gradient and smaller heat affected zone (HAZ) resulting in much longer tool life in compared with un-coated tools.