Patent ID: 8758890

Claim:
A coated cutting tool comprising: a substrate and a PVD-coating, wherein the coating comprises an outermost zone C being a nitride, carbide, boride, or mixtures thereof, of Si and at least two additional elements selected from Al, Y, and groups 4, 5 or 6 of the periodic table, wherein zone C is free from a compositional gradient of an average content of Si, and wherein zone C has an aperiodic, multilayered structure of alternating individual layers X and Y having different compositions from each other, wherein the coating further comprises a zone A closest to the substrate and a transitional zone B between zone A and zone C where: zone A is essentially free from Si, zone B comprises a compositional gradient of the average content of Si, where the average content of Si is increasing towards zone C, and zone B has an aperiodic multilayer structure of alternating individual layers X and Y having different compositions from each other.