Surface-coated cutting tool

Abstract

A surface-coated cutting tool includes a substrate and a coating film. The coating film includes an alternate layer. The alternate layer includes a first layer having a first composition and a second layer having a second composition. The alternate layer is formed by alternately stacking at least one first layer and at least one second layer. The first layer and the second layer each have a thickness not smaller than 2 nm and not greater than 100 nm. The first composition is expressed as TiaAlbSicN (0.25≤a≤0.45, 0.55≤b≤0.75, 0≤c≤0.1, a+b+c=1). The second composition is expressed as TidAleSifN (0.35≤d≤0.55, 0.45≤e≤0.65, 0≤f≤0.1, d+e+f=1). The first composition and the second composition satisfy a condition of 0.05≤d−a≤0.2 and 0.05≤b−e≤0.2.

Dependencies are inferred from the claim text.