Patent ID: 7960015

Claim:
A workpiece having a surface whereas at least parts of said surface are coated with a wear resistant multilayered hard coating deposited by a PVD process, whereas the hard coating comprises at least a first supporting layer and a second layer, which exhibits a nanocrystalline growth structure in the SEM cross-section, whereas the first layer is interposed between the workpiece and the second layer, whereas the first layer comprises a coating material of the following composition (Ti a Al 1-a )N 1-x-y C x O y whereas 0.4<a<0.6, and 0≦x and y<0.3, or (Al b Cr 1-b )N 1-x-y C x O y whereas 0.5<b<0.7, and 0≦x and y<0.3; the second layer comprises a coating material of the following composition (Al 1-c-d-e Cr c Si d M e )N 1-x-y C x O y whereas M stands for at least one element of the transition metals of group 4, 5, 6 of the periodic system except Chromium and 0.2<c≦0.35,0<d≦0.20,0<e≦0.04.