Multilayer-coated cutting tool

Abstract

A multilayer-coated cutting tool comprising a cutting tool substrate, and a multilayer coating film comprising a first hard coating film formed on the substrate and a second hard coating film formed on the first hard coating film, the first hard coating film comprising one or more metallic elements selected from the group consisting of Ti, Al and Cr, and one or more non-metallic elements selected from the group consisting of N, B, C and O; and the second hard coating film comprising Si and one or more metallic elements selected from the group consisting of metallic elements of Groups 4a, 5a and 6a of the Periodic Table and Al, and one or more non-metallic elements selected from the group consisting of N, B, C and O; the second hard coating film being a composition-segregated polycrystalline film comprising a phase having a relatively high Si concentration and a phase having a relatively low Si concentration.

Dependencies are inferred from the claim text.