US Patent 11084103 Coated cutting tool

A coated cutting tool comprising a substrate and a coating layer formed on a surface of the substrate, the coating layer including an alternating laminate structure in which two or more compound layers of each of two or three or more kinds, each kind having a different composition, are laminated in an alternating manner, wherein:the alternating laminate structure is constituted by:a compound layer containing a compound having a composition represented by formula (1) below:(TixMySiz)N  (1)[wherein M denotes an element of at least one kind selected from the group consisting of Zr, Hf, V, Nb, Ta, Cr, Mo, W and Al, x denotes an atomic ratio of Ti based on a total of Ti, an element denoted by M and Si, y denotes an atomic ratio of the element denoted by M based on a total of Ti, the element denoted by M and Si, z denotes an atomic ratio of Si based on a total of Ti, the element denoted by M and Si, x satisfies 0.20≤x≤0.50, y satisfies 0.20≤y≤0.50, z satisfies 0.03≤z≤0.30, and x, y and z satisfy x+y+z=1]; anda compound layer containing a compound having a composition represented by formula (2) below:(TiaMbSic)N  (2)[wherein M denotes an element of at least one kind selected from the group consisting of Zr, Hf, V, Nb, Ta, Cr, Mo, W and Al, a denotes an atomic ratio of Ti based on a total of Ti, an element denoted by M and Si, b denotes an atomic ratio of the element denoted by M based on a total of Ti, the element denoted by M and Si, c denotes an atomic ratio of Si based on a total of Ti, the element denoted by M and Si, a satisfies 0.20≤a≤0.49, b satisfies 0.21≤b≤0.50, c satisfies 0.04≤c≤0.30, and a, b and c satisfy a+b+c=1];an absolute value of a difference between an amount of a specific metal element contained in a compound layer which constitutes the alternating laminate structure based on an amount of all the metal elements contained therein and an amount of the specific metal element contained in another compound layer which is adjacent to the compound layer and which constitutes the alternating laminate structure based on an amount of all the metal elements contained therein, is more than 0 atom % and less than 5 atom %; and an average thickness of each of the compound layers is from 1 nm or more to 50 nm or less, and an average thickness of the alternating laminate structure is from 1.0 μm or more to 15.0 μm or less.