Cutting tool

Abstract

A cutting tool includes a substrate and a coating film provided on the substrate, wherein the coating film includes a first layer, the first layer consists of a multilayer structure in which a first unit layer and a second unit layer are alternately layered, an average thickness of the first unit layer is 2 nm or more and 50 nm or less, an average thickness of the second unit layer is 2 nm or more and 50 nm or less, an average thickness of the first layer is 1.0 μm or more and 20 μm or less, the first unit layer consists of TiaAl1-a-bBbN, where 0.30≤a≤0.50, and 0≤b≤0.10, the second unit layer consists of TicAl1-cN, where 0.70≤c≤1.00, and in the first layer, a percentage (T2/T1)×100 of T2, the number of atoms of titanium, to T1, a total of the numbers of atoms of titanium and aluminum, is 60% or more.

Dependencies are inferred from the claim text.