Patent ID: 11931811
Assignee: TUNGALOY CORPORATION
Field: Surface technology, coating (Chemistry)
Classification: CPC B  C | IPC B  C

Claim 0:
1. A coated cutting tool comprising a substrate containing a cubic boron nitride-containing sintered body, and a coating layer formed on the substrate,
wherein the coating layer comprises a lowermost layer and an alternating laminate structure in this order from the substrate side toward a surface side of the coating layer,
the lowermost layer contains a compound having a composition represented by the following formula (1),

(Al1-xCrx)N  (1), [where in the formula (1), x represents an atomic ratio of a Cr element relative to a total ratio of an Al element and the Cr element, and satisfies 0.20≤x≤0.50],
an average thickness of the lowermost layer is 0.01 μm or more and 0.2 μm or less,
the alternating laminate structure is an alternating laminate structure including a first compound layer containing a compound having a composition represented by the following formula (2) and a second compound layer containing a compound having a composition represented by the following formula (3) alternately laminated repeatedly twice or more,

(Al1-y1Cry1)N  (2), [where in the formula (2), y1 represents an atomic ratio of a Cr element relative to a total ratio of an Al element and the Cr element, and satisfies 0.10≤y1≤0.60],

(Al1-y2Cry2)N  (3), [where in the formula (3), y2 represents an atomic ratio of a Cr element relative to a total ratio of an Al element and the Cr element, and satisfies 0.10≤y2≤0.60],
in the alternating laminate structure, the first compound layer and the second compound layer are two kinds of compound layers having mutually different atomic ratios y1 and y2,
an average thickness of the entire alternating laminate structure is 0.1 μm or more and 1.2 μm or less,
an average thickness of the entire coating layer is 0.2 μm or more and 1.3 μm or less, and
the coating layer comprises a crystal of a cubic system, and a compressive residual stress at the cubic crystal (111) plane is 3.0 GPa or less.