Patent ID: 8545997

Claim:
A coated cutting tool comprising a substrate and a coating; wherein: the coating comprises at least one multi-nano-layer, comprising a plurality of nano-composite nano-layers with at least one second nano-layer having a thickness of from 1 nm to 100 nm between the nano-composite nano-layers; wherein: the second nano-layer is crystalline; the nano-composite nano-layers consist of crystalline (Ti x Al y Cr z )N embedded in an amorphous Si 3 N 4 matrix, wherein 0.25≦x ≦0.75, 0.25≦y ≦0.75, 0.05≦z ≦0.2, 0.85≦x+y+z ≦0.97, and 1-x-z <0.75; the atomic ratio of silicon is 1-x-y-z; and a thickness of the nano-composite nano-layers is from 1 nm to 100 nm.