# US 12,109,625 B2 · Surface-coated TiN-based cermet cutting tool in which hard coating layer exhibits excellent chipping resistance

> Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt

- Number: US 12,109,625 B2
- Document ID: US12109625B2
- Status: Granted
- Kind: B2
- Application number: 17/279,311
- Filed: 2019-09-25
- Published: 2022-02-24
- Granted: 2024-10-08
- Earliest claimed: 2018-09-28
- Assignees: Mitsubishi Materials Corporation
- Applicants: Mitsubishi Materials Corporation
- Inventors: Makoto Igarashi; Kazutaka Fujiwara
- Web page: https://patentgrep.com/patent/US12109625B2

## CPC

- B23B 27/148: {Composition of the cutting inserts}
- C22C 29/16: based on nitrides {(containing cubic BN or wurtzitic BN and diamond C22C26/00)}
- C23C 16/34: Nitrides {(C23C16/303 takes precedence)}
- B23B 2228/105: with specified thickness
- B23B: TURNING; BORING (arrangements for copying or controlling B23Q)
- C22C: ALLOYS (treatment of alloys C21D, C22F)
- C23C: COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL (making metal-coated products by extrusion B21C23/22; covering with metal by connecting pre-existing layers to articles, see the relevant places, e.g. B21D39/00, B23K; metallising of glass C03C; metallising mortars, concrete, artificial stone, ceramics or natural stone C04B41/00; enamelling of, or applying a vitreous layer to, metals C23D; treating metal surfaces or coating of metals by electrolysis or electrophoresis C25D; single-crystal film growth C30B; by metallising textiles D06M11/83; decorating textiles by locally metallising D06Q1/04)

## Abstract

A surface-coated TiN-based cermet cutting tool is a surface-coated TiN-based cermet cutting tool, in which a TiN-based cermet containing a TiN phase as a hard phase component is used as a body, and a hard coating layer including a titanium carbonitride layer and an aluminum oxide layer is formed on a surface, in which a linear expansion coefficient of the TiN-based cermet is set to 9.0×10−6 (/K) or more, a thermal conductivity is set to 30 (W/m·K) or more, and a residual compressive stress of the hard coating layer is set to 600 to 2,000 MPa, and particularly 600 to 2,000 MPa even in an as-deposited state by adjusting component composition and the like of the TiN-based cermet.

## Claims

### Claim 1

A surface-coated TiN-based cermet cutting tool, comprising:
a body; and
a hard coating layer formed on a surface of the body,
wherein a TiN-based cermet containing a TiN phase as a hard phase component is used as the body,
wherein the hard coating layer includes at least one layer of a titanium carbonitride layer and an aluminum oxide layer,
wherein the body has a linear expansion coefficient of 9.0×10−6 (/K) or more and a thermal conductivity of 30 (W/m·K) or more,
each of the titanium carbonitride layer and the aluminum oxide layer constituting the hard coating layer has a residual compressive stress of 600 to 2,000 MPa,
wherein the TiN-based cermet consists of 70 to 94 area % of the TiN phase, 1 to 25 area % of a Mo2C phase, and a remainder of a binder phase,
a component of the binder phase consists of Fe and Ni,
a total area ratio of Fe and Ni is 5 to 15 area %, and
an amount of Ni with respect to a total amount of Fe and Ni is 15 to 35 mass %.

### Claim 2 (depends on 1)

The surface-coated TiN-based cermet cutting tool according to claim 1,
wherein each of the titanium carbonitride layer and the aluminum oxide layer constituting the hard coating layer has a residual compressive stress of 600 to 2,000 MPa in an as-deposited state.