Friction Coefficient of the PVD-AlCrN Coated Cemented Carbide and Hardened Steel Tribo-Pair Under Dry Sliding

Can a simple tribometric experiment be used to estimate the tool-chip interface friction coefficient in high speed cutting (HSC) to provide a preliminary assessment of the effect of using a new tool coating on the tool-chip interface friction? Heat generated in the machining zone is a primary factor that governs the performance of machining operations, and tool-chip frictional heating is a primary cause of heat generation. There is no method available yet which makes it practically possible to measure the tool-chip interface friction coefficient directly. Additionally, machining experiments are expensive. In the work reported here, frictional conditions resembling those at the tool chip interface are experimentally simulated on a rotary pin-on-disc tribometer to estimate the interface frictional coefficient. Based on such experiments, the effect of applying physical vapour deposited (PVD) thin film AlCrN coatings on cemented tungsten carbide tools for HSC of hardened steels is investigated. The possibility of applying results obtained from simpler, less expensive tribological experiments to machining operations is discussed.