Wear mechanisms of coated carbide tools

Abstract

AbstractCemented carbide inserts, both uncoated and coated with single or composite layers of TiC, TiN, or Al2O3, were used to cut En. 8 and En 24 steel at speeds between 183 and 305 min−1 Quick-stop specimens and tool-temperature estimates demonstrated that conditions at the tool/work interface were essentially similar for uncoated tools and for all types of coated tool tested. The flank and rake-face wear rates of coated tools were estimated to be respectively ∼ 10 and 100 times less than that of an uncoated carbide, smaller differences between the rates of flank and rake-face wear of TiC, TiN, and Al2O3 coatings being observed. On the rake face, wear of TiC coatings was by atomic diffusion and discrete plastic deformation, while TiN coatings and uncoated cemented carbide were worn by atomic diffusion. Al2O3 coatings were worn principally by discrete plastic deformation. Flank wear of both coated and uncoated tools was principally by atomic diffusion. Al2O3 and TiN coatings showed a greater resistance t...