Coated cutting tool and a method for coating the cutting tool

Patent metadata

Field	Value
Publication number	US-11292064-B2
Application number	US-201816642724-A
Country	US
Kind code	B2
Filing date	Aug 30, 2018
Priority date	Aug 30, 2017
Publication date	Apr 5, 2022
Grant date	Apr 5, 2022

Abstract

A coated cutting tool includes a substrate with a coating having a total thickness of 0.25-30 μm. The coating has a first layer and a second layer, the first layer being a wear resistant PVD deposited layer having a thickness of 0.2-15 μm arranged between the substrate and the second layer, and wherein the second layer is a Cr layer.

First claim

The invention claimed is:

1. A coated cutting tool comprising a substrate with a coating having a total thickness of 0.25-30 μm, wherein the coating includes a first layer and a second layer, and wherein the first layer is a wear resistant PVD deposited layer having a thickness of 0.2-15 μm, the first layer being arranged between the substrate and the second layer, the first layer being
a (Ti 1−x Al x )N y layer with 0.1<x<0.7 and 0.6<y<1.1, or
a NaCl structured (Ti 1−y Al y )N w /(Ti 1−a Si a )N b nanolaminate with sublayer thickness between 5 and 50 nm, where 0.1<v<0.7, 0.7<w<1.1, 0.02<a<0.25, and 0.7<b<1.1, or
a (Ti 1−m Si m )N n layer, where 0≤m<0.25, and 0.7<n<1.1, or
a (Cr 1−c Al c )N d layer, where 0.5<c<0.9, and 0.7<d<1.1, or
a (Cr 1−e Al e ) 2 O 3 layer, where 0.5<e<0.9, and wherein the second layer is a Cr layer, the Cr layer being an outermost layer of the coating.

2. The coated cutting tool according to claim 1 , wherein a thickness of the Cr layer is 0.05-5 μm.

3. The coated cutting tool according to claim 1 , wherein the Cr layer is a PVD deposited layer.

4. The coated cutting tool according to claim 1 , wherein the Cr layer has a body-centered cubic structure with a crystallographic orientation relation of 0.3<R1<1, where R 1 =I (110) /(I (110) +I (200) +I (211) , and where 1 (110) , 1 (200) , and 1 (211) are the XRD peak areas as extracted from the pseudo-Voigt peak profile fitting results of θ-2θ scans obtained with CuKα radiation for the bcc structure Cr layer diffraction peaks.

5. The coated cutting tool according to claim 1 , wherein the first layer is a (Ti 1−x Al x )N y layer with 0.1<x<0.7 and 0.7<y<1.1.

6. The coated cutting tool according to claim 1 , wherein the first layer is a NaCl structure c-(Ti 1−x Al x )N y layer, where 0.1<x<0.7, and 0.7<y<1.1.

7. The coated cutting tool according to claim 5 , wherein 0.5<x<0.6.

8. The coated cutting tool according to claim 1 , wherein the first layer is a NaCl structured (Ti 1−v Al v )N w /(Ti 1−a Si a )N b nanolaminate with a sublayer thickness between 5 and 50 nm, and wherein 0.4<v<0.7 , , 0.7<w<1.1,0.02<a<0.25, and 0.7<b<1.1.

9. The coated cutting tool according to claim 1 , wherein the first layer is a (Ti 1−m Si m )N n layer, where 0<m<0.15, and 0.7<n<1.1.

10. The coated cutting tool according to claim 1 , wherein the first layer is a (Cr 1−c Al c )N d layer, where 0.5<c<0.8, and 0.7<d<1.1.

11. The coated cutting tool according to claim 1 , wherein the first layer is a (Cr 1−e Al e ) 2 O 3 layer, where 0.5<e<0.8.

12. The coated cutting tool according to claim 1 , wherein a ratio between the Cr layer thickness and the total coating thickness is between 0.01 and 2.

13. The coated cutting tool according to claim 1 , wherein the first layer has a hardness H>20 GPa.

14. The coated cutting tool according to claim 1 , wherein the first layer has a NaCl type structure and the Cr layer has a body-centered cubic structure, the ratio, R4, between the XRD peak intensity of the body-centered cubic Cr peak and the XRD peak intensity of the NaCl structure peak originating from the first layer is 0.05<R4<30, where XRD peak intensity is evaluated as the peak area extracted from the pseudo-Voigt peak profile fitting results of θ-2θ scans obtained with CuKα radiation.

15. The coated cutting tool according to claim 1 , wherein the substrate comprises at least one of the following: cemented carbide, cermet, ceramics, steel and cubic boron nitride.

16. The coated cutting tool according to claim 15 , wherein the cemented carbide includes WC and 4-15 wt % Co.

17. A method for producing of a coated cutting tool comprising the steps of:
applying a substrate of cemented carbide, cermet, ceramic, steel or cubic boron nitride with a hard and wear resistant coating having a thickness of 0.25-30 μm by means of PVD (physical vapor deposition) techniques, such as cathodic arc deposition, wherein the coating includes a first layer, the first layer being
a (Ti 1−x Al x )N y layer with 0.1<x<0.7 and 0.6<y<1.1, or
a NaCl structured (Ti 1−y Al v )N w /(Ti 1−a Si a )N b nanolaminate with sublayer thickness between 5 and 50 nm, where 0.1<v<0.7, 0.7<w<1.1, 0.02<a<0.25, and 0.7<b<1.1, or
a (Ti 1−m Si m )N n layer, where 0≤m<0.25, and 0.7<n<1.1, or
a (Cr 1−c Al c )N d layer, where 0.5<c<0.9, and 0.7<d<1.1, or
a (Cr 1−e Al e ) 2 O 3 layer, where 0.5<e<0.9
and a second layer, the second layer being a Cr layer arranged as an outermost layer of the coating; and
growing the Cr layer by using pure Cr cathodes applying an evaporation current between 50 A and 200 A, a gas atmosphere containing pure Ar at a total gas pressure between 1.0 Pa and 7.0 Pa, and applying a deposition temperature between room temperature and 500° C.

18. The method according to claim 17 , further comprising growing a first layer being a (Ti 1−x Al x )N y -layer, with 0.1<x<0.7 and 0.7<y<1.1, between the substrate and the Cr layer, by cathodic arc evaporation with an evaporation current between 50 A and 200 A using composite and/or alloyed (Ti,Al) cathodes, and in a reactive gas atmosphere containing N 2 and optionally mixed with Ar, at a total gas pressure between 1.0 Pa and 7.0 Pa, with a negative substrate bias between 0 V and 300 V, at a temperature between 200° C. and 800° C.

19. A coated cutting tool comprising a substrate with a coating having a total thickness of 0.25-30 μm, wherein the coating includes a first layer and a second layer, and wherein the first layer is a wear resistant PVD deposited layer having a thickness of 0.2-15 μm, the first layer being arranged between the substrate and the second layer, and wherein the second layer is a Cr layer, the Cr layer being an outermost layer of the coating, wherein the Cr layer has a body-centered cubic structure with a crystallographic orientation relation of 0.3<R1<1, where R1=I (110) /(I (110) +I (200) +I (211) ), and where I (110) , 1 (200) , and 1 (211) are the XRD peak areas as extracted from the pseudo-Voigt peak profile fitting results of θ-2θ scans obtained with CuKα radiation for the bcc structure Cr layer diffraction peaks.

Assignees

• Seco Tools Ab

Inventors

• Fallqvist Mikael
• Andersson Jon

Classifications

• C23C14/18 Primary

  on other inorganic substrates · CPC title

• B23C5/16

  characterised by physical features other than shape · CPC title

• B23C2228/10

  Coating · CPC title

• C23C30/005

  on hard metal substrates · CPC title

• C23C14/325

  Electric arc evaporation · CPC title