Cutting tool

Patent metadata

Field	Value
Publication number	US-12226836-B2
Application number	US-202318571264-A
Country	US
Kind code	B2
Filing date	Jun 22, 2023
Priority date	Jun 22, 2023
Publication date	Feb 18, 2025
Grant date	Feb 18, 2025

Abstract

A cutting tool including a substrate and a coated film arranged on the substrate, in which the coated film includes a first layer positioned on the substrate, a second layer positioned on the first layer, and a third layer positioned on the second layer, the first layer is composed of titanium carbonitride, the second layer is composed of aluminum oxide, the third layer is composed of titanium carbonitride, a residual stress X of the first layer, a residual stress Y of the second layer and a residual stress Z of the third layer satisfy a relationship of formula 1.

First claim

The invention claimed is:

1. A cutting tool comprising a substrate and a coated film arranged on the substrate,
wherein the coated film comprises a first layer positioned on the substrate, a second layer positioned on the first layer, and a third layer positioned on the second layer,
wherein the first layer is composed of titanium carbonitride,
wherein the second layer is composed of aluminum oxide,
wherein the third layer is composed of titanium carbonitride,
wherein a residual stress X of the first layer, a residual stress Y of the second layer and a residual stress Z of the third layer satisfy a relationship of formula 1:
X<Y<Z  formula 1,

wherein the residual stress X of the first layer is −1.0 GPa or more and −0.3 GPa or less,
wherein the residual stress Y of the second layer is −0.5 GPa or more and 0.1 GPa or less, and
wherein the residual stress Z of the third layer is −0.3 GPa or more and 0.4 GPa or less.

2. The cutting tool according to claim 1 , wherein a thickness of the first layer is 3 μm or more and 15 μm or less.

3. The cutting tool according to claim 2 , wherein the residual stress X of the first layer is −0.8 GPa or more and −0.5 GPa or less,
wherein the residual stress Y of the second layer is −0.3 GPa or more and −0.1 GPa or less, and
wherein the residual stress Z of the third layer is −0.1 GPa or more and 0.2 GPa or less.

4. The cutting tool according to claim 1 , wherein a thickness of the second layer is 3 μm or more and 15 μm or less.

5. The cutting tool according to claim 4 , wherein the residual stress X of the first layer is −0.8 GPa or more and −0.5 GPa or less,
wherein the residual stress Y of the second layer is −0.3 GPa or more and −0.1 GPa or less, and
wherein the residual stress Z of the third layer is −0.1 GPa or more and 0.2 GPa or less.

6. The cutting tool according to claim 1 , wherein a thickness of the third layer is 2 μm or more and 4 μm or less.

7. The cutting tool according to claim 6 , wherein the residual stress X of the first layer is −0.8 GPa or more and −0.5 GPa or less,
wherein the residual stress Y of the second layer is −0.3 GPa or more and −0.1 GPa or less, and
wherein the residual stress Z of the third layer is −0.1 GPa or more and 0.2 GPa or less.

8. The cutting tool according to claim 1 , wherein a thickness of the coated film is between 6 μm and 30 μm.

9. The cutting tool according to claim 1 , wherein Y-X is between 0.1 and 0.6.

10. The cutting tool according to claim 1 , wherein Y-Z is between −0.6 and −0.1.

11. The cutting tool according to claim 1 , wherein Y-X is between 0.1 and 0.6, and
wherein Y-Z is between −0.6 and −0.1.

12. The cutting tool according to claim 1 , wherein a thickness of the coated film is between 6 μm and 30 μm,
wherein Y-X is between 0.1 and 0.6, and
wherein Y-Z is between −0.6 and −0.1.

13. The cutting tool according to claim 1 , wherein the substrate is comprised of cemented carbides.

14. The cutting tool according to claim 1 , wherein the residual stress of the coated film is changed using blast processing.

15. The cutting tool according to claim 1 , wherein a thickness of the first layer is 3 μm or more and 15 μm or less, and
wherein a thickness of the second layer is 3 μm or more and 15 μm or less.

16. The cutting tool according to claim 15 , wherein a thickness of the third layer is 2 μm or more and 4 μm or less.

17. The cutting tool according to claim 16 , wherein a thickness of the coated film is between 6 μm and 30 μm.

18. The cutting tool according to claim 17 , wherein Y-X is between 0.1 and 0.6.

19. The cutting tool according to claim 18 , wherein Y-Z is between −0.6 and −0.1.

20. The cutting tool according to claim 19 , wherein the residual stress X of the first layer is −0.8 GPa or more and −0.5 GPa or less,
wherein the residual stress Y of the second layer is −0.3 GPa or more and −0.1 GPa or less, and
wherein the residual stress Z of the third layer is −0.1 GPa or more and 0.2 GPa or less.

Assignees

• Sumitomo Electric Hardmetal Corp

Inventors

• Hikiji Masahito
• Yamanishi Takato
• Yamakawa Takahiro

Classifications

• B23B2228/105

  with specified thickness · CPC title

• B23B2224/04

  Aluminium oxide · CPC title

• B23B2224/32

  Titanium carbide nitride (TiCN) · CPC title

• B23B27/148 Primary

  Composition of the cutting inserts · CPC title

• C23C28/42

  characterized by the composition of the alternating layers · CPC title