OUTIL DE COUPE À REVÊTEMENT DE SURFACE DOTÉ D'UNE COUCHE DE REVÊTEMENT DUR PRÉSENTANT UNE EXCELLENTE RÉSISTANCE À L'ÉCAILLAGE ET UNE EXCELLENTE RÉSISTANCE DE PELAGE

摘要

Provided is a surface-coated cutting tool in which a hard coating layer has excellent chipping resistance and peeling resistance during high-speed intermittent cutting and exhibits excellent cutting performance during long-term use. In the surface-coated cutting tool in which the hard coating layer including at least three layers of an upper layer α, an adhesion layer β, and a lower layer γ is formed, the upper layer α is formed of an α-AlOlayer formed under low temperature conditions, the adhesion layer β includes at least a TiCN layer having a layer thickness of at least 0.5 µm or more in an outermost layer being in contact with an interface with the upper layer α and contains 0.5 to 3 µm only to a maximum depth of 0.5 µm toward the inside in a layer thickness direction of the TiCN layer from the interface between the TiCN layer and the upper layer α, and the lower layer γ is formed of (TiAl)(CN) of a single phase of a NaCl type face-centered cubic structure, in which an average content ratio Xof Al and an average content ratio Yof C in this composition formula satisfy 0.60 ≤ X≤ 0.95 and 0 ≤ Y≤ 0.005 (Xand Yare in atomic ratio).