High performance tools that exhibit reduced crater wear particularly in dry machining operations

摘要

Coating system deposited on a surface of a substrate comprising at least one multilayer film formed of alternating nano-layers A and B deposited on top of each other, in which nano-layers A contain aluminum and chromium boron nitride and nano-layers B contain nitride of aluminum and chromium, but do not contain boron, characterized in that nanocaps A have a region with the highest boron content and a region with a lower boron content, in which the region that has the lowest boron content is the region adjacent to nanolayers B, in which the sum of the thickness of a nanolayer A and the thickness of a nanolayer B deposited on top of each other in the multilayer film is not more than 200 nm, and the ratio between the thickness of a nanolayer B and the thickness of a nanolayer A deposited on top of one another in the multilayer film is not greater than 2, and in which the composition of the element of the nanolayers A, or if it occurs in the region of the nanolayers A which has a higher boron content, is defined by the formula (AlxCr1-x-zBz) N with xyz being respectively the concentration of Al and the concentration of B in atomic percentage when only the elements Al, Cr and B are considered for the calculation , with x = 50 - 80% atomic and z = 3 - 30% atomic and x + z = 90% atomic, and in which the composition of the element of nanocaps B is defined by the formula (AlyCr1-y) N with y the concentration of Al being atomic percentage when only the elements Al and Cr are considered for the calculation, with y = 50 - 80% atomic.