# US 7,410,707 B2 · Surface-coated cutting tool

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

- Number: US 7,410,707 B2
- Document ID: US7410707B2
- Status: Granted
- Kind: B2
- Application number: 10/560,400
- Filed: 2004-12-02
- Published: 2006-07-13
- Granted: 2008-08-12
- Earliest claimed: 2003-12-05
- Assignees: Sumitomo Electric Hardmetal Corp.
- Inventors: Haruyo Fukui; Naoya Omori
- Web page: https://patentgrep.com/patent/US7410707B2

## CPC

- C23C 30/005: {on hard metal substrates}
- Y10T 428/24975: No layer or component greater than 5 mils thick
- 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)
- Y10T: TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION

## Abstract

The present invention provides a surface-coated cutting tool comprising a coating film on a base, while the coating film comprises a hard layer constituted of a compound selected from a nitride, a carbonitride, an oxynitride and a carboxynitride of at least one primary element selected from a group consisting of the metals belonging to the groups 4a, 5a and 6a of the periodic table as well as B, Al and Si, and the hard layer satisfies the following: (a) (hmax−hf)/hmax is at least 0.2 and not more than 0.7, assuming that hmax represents the maximum indentation depth and hf represents the indentation depth (dent depth) after unloading in a hardness test according to nanoindentation, (b) the thickness of the hard layer is at least 0.5 μm and not more than 15 μm, and (c) the hardness according to nanoindentation is at least 20 GPa and not more than 80 GPa.

## Claims

### Claim 1

A surface-coated cutting tool comprising a coating film on a base, wherein
said coating film comprises a hard layer constituted of a compound selected from a nitride, a carbonitride, an oxynitride and a carboxynitride of at least one primary element selected from a group consisting of the metals belonging to the groups 4a, 5a and 6a of the periodic table as well as B, Al and Si, and
said hard layer satisfies the following:
(a) (hmax−hf)/hmax is at least 0.2 and not more than 0.7, assuming that hmax represents the maximum indentation depth and hf represents the indentation depth (dent depth) after unloading, in a hardness test according to nanoindentation,
(b) the thickness of the hard layer is at least 0.5 μm and not more than 15 μm, and
(c) the hardness according to nanoindentation is at least 20 GPa and not more than 80 GPa.

### Claim 2 (depends on 1)

The surface-coated cutting tool according to claim 1, wherein
the hard layer is composed of a compound selected from a nitride, a carbonitride, an oxynitride and a carboxynitride of Ti, Al and Si.

### Claim 3 (depends on 1)

The surface-coated cutting tool according to claim 1, wherein
the hard layer is composed of a compound selected from a nitride, a carbonitride, an oxynitride and a carboxynitride of (Ti1-x-yAlxSiy) (0≦x≦0.7, 0≦y≦0.2).

### Claim 4 (depends on 1)

The surface-coated cutting tool according to claim 1, wherein
the primary element contains at least one addition element selected from a group consisting of Mg, Ca, V, Zn and Zr, and
the primary element contains less than 10 atomic % of said addition element.

### Claim 5 (depends on 1)

The surface-coated cutting tool according to claim 1, wherein
the hard layer is composed of a compound selected from a nitride, a carbonitride, an oxynitride and a carboxynitride of (Al1-a-b-cCraVbSic) (0≦a≦0.4, 0<b≦0.4, 0≦c≦0.2, a+b≠0, 0<a+b+c<1).

### Claim 6 (depends on 1)

The surface-coated cutting tool according to claim 1, wherein
the coating film further comprises an intermediate layer formed between the base surface and the hard layer, and
said intermediate layer is constituted of any of a nitride of Ti, a nitride of Cr, Ti and Cr.

### Claim 7 (depends on 6)

The surface-coated cutting tool according to claim 6, wherein
the thickness of the intermediate layer is at least 0.005 μm and not more than 0.5 μm.

### Claim 8 (depends on 1)

The surface-coated cutting tool according to claim 1, wherein
the base is constituted of any of cemented carbide comprising WC, cermet, high-speed steel, ceramics, a cubic boron nitride sintered body, a diamond sintered body, a silicon nitride sintered body and a sintered body containing aluminum oxide and titanium carbide.

### Claim 9 (depends on 1)

The surface-coated cutting tool according to claim 1, wherein
the surface-coated cutting tool is any of a drill, an end mill, a cutting edge-replaceable insert for milling, a cutting edge-replaceable insert for turning, a metal saw, a gear cutting tool, a reamer and a tap.

### Claim 10 (depends on 1)

The surface-coated cutting tool according to claim 1, wherein
the coating film is applied by physical vapor deposition.

### Claim 11 (depends on 10)

The surface-coated cutting tool according to claim 10, wherein
the physical vapor deposition is arc ion plating or magnetron sputtering.

### Claim 12 (depends on 1)

The surface-coated cutting tool according to claim 1, wherein said hard layer is made up of crystal grains having an average particle diameter in a range from 2 nm to 100 nm.

### Claim 13 (depends on 1)

The surface-coated cutting tool according to claim 1, wherein said hardness is at least 55 GPa.

### Claim 14 (depends on 1)

The surface-coated cutting tool according to claim 1, wherein said (hmax−hf)/hmax is less than 0.28.

### Claim 15 (depends on 1)

The surface-coated cutting tool according to claim 1, wherein said (hmax−hf)/hmax is at least 0.43.

### Claim 16 (depends on 1)

The surface-coated cutting tool according to claim 1, wherein said (hmax−hf)/hmax is at least 0.48.

### Claim 17 (depends on 1)

The surface-coated cutting tool according to claim 1, wherein said (hmax−hf)/hmax is at least 0.54.

### Claim 18 (depends on 1)

The surface-coated cutting tool according to claim 1, having such characteristics as result from fabricating said surface-coated cutting tool by mounting said base on a base holder, performing a film forming process in a chamber to deposit said hard layer on said base, stopping said film forming process and filling helium gas into said chamber, and quenching by water-cooling said base holder.