Coated cutting tool

Patent metadata

Field	Value
Publication number	US-9725811-B2
Application number	US-201414772580-A
Country	US
Kind code	B2
Filing date	Mar 4, 2014
Priority date	Mar 4, 2013
Publication date	Aug 8, 2017
Grant date	Aug 8, 2017

Abstract

A coated cutting tool has a substrate and a coating layer. At least one layer of the coating layer is a coarse grain layer with an average layer thickness of 0.2 to 10 μm and an average grain diameter in excess of 200 nm measured at the direction parallel to the interface of the coating layer. A composition of the layer is represented by (Al a Ti b M c )X, wherein M represents at least one of Zr, Hf, V, Nb, Ta, Cr, Mo, W, Y, B and Si, X represents at least one of C, N and O, and a, b and c represents atomic ratios of Al, Ti and M relative to one another such that 0.30≦a≦0.65, 0.35≦0.70, 0≦c≦0.20 and a+b+c=1.

First claim

The invention claimed is:

1. A coated cutting tool which comprises
a substrate and a coating layer formed on a surface of the substrate,
at least one layer of the coating layer being a coarse grain layer having an average grain diameter Lx measured at a direction parallel to an interface of the coating layer and the substrate exceeding 200 nm, and a composition of which being represented by (Al a Ti b M c )X, wherein:
a grain diameter ratio (Ly/Lx) of an average grain diameter Ly of the coarse grain layer measured at a direction perpendicular to an interface between the coating layer and the substrate to said average grain diameter Lx of the coarse grain layer measured at a direction parallel to an interface between the coating layer and the substrate is 0.7 or more and less than 1.5,
M represents at least one kind of an element(s) selected from the group consisting of Zr, Hf, V, Nb, Ta, Cr, Mo, W, Y, B and Si,
X represents at least one kind of an element(s) selected from the group consisting of C, N and O,
a represents an atomic ratio of an Al element based on a total of the Al element, a Ti element and an M element,
b represents an atomic ratio of a Ti element based on a total of an Al element, the Ti element and an M element,
c represents an atomic ratio of an M element based on a total of an Al element, a Ti element and the M element,
a, b and c each satisfy 0.30≦a≦0.65, 0.35≦b≦0.70, 0≦c≦0.20 and a+b+c=1, and
an average layer thickness of the coarse grain layer being 0.2 to 10 μm.

2. The coated cutting tool according to claim 1 , wherein a, b and c each satisfy 0.30≦a≦0.50, 0.50≦b≦0.70, 0≦c≦0.20 and a+b+c=1.

3. The coated cutting tool according to claim 1 , wherein X of the coarse grain layer represents N.

4. The coated cutting tool according claim 1 , wherein an average grain diameter Lx of the coarse grain layer measured at a direction parallel to an interface of the coating layer and the substrate is in the range of 400 nm to 1,000 nm.

5. The coated cutting tool according to claim 1 , wherein the coarse grain layer is cubic.

6. The coated cutting tool according to claim 5 , wherein a full width at half maximum intensity (FWHM) of an X-ray diffraction peak of a ( 200 ) plane of the coarse grain layer is 0.6° or less.

7. The coated cutting tool according to claim 1 , wherein the coating layer contains a lower layer formed on a surface of the substrate and a coarse grain layer formed on a surface of the lower layer, and the lower layer is a single layer or a multilayer containing at least one kind of a material(s) selected from
a metal containing at least one kind of metallic elements selected from the group consisting of Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, W, Y, Al and Si, and
a compound containing at least one kind of these metallic elements and at least one kind of nonmetallic elements selected from the group consisting of carbon, nitrogen, oxygen and boron.

8. The coated cutting tool according to claim 1 , wherein the coarse grain layer is an uppermost layer.

9. A coated cutting tool which comprises
a substrate and a coating layer formed on a surface of the substrate,
at least one layer of the coating layer being a coarse grain layer having an average grain diameter Lx measured at a direction parallel to an interface between the coating layer and the substrate exceeding 200 nm, and a composition of which being represented by (Al d Cr e L f )Z, wherein:
a grain diameter ratio (Ly/Lx) of an average grain diameter Ly of the coarse grain layer measured at a direction perpendicular to an interface between the coating layer and the substrate to said average grain diameter Lx of the coarse grain layer measured at a direction parallel to an interface between the coating layer and the substrate is 0.7 or more and less than 1.5,
L represents at least one kind of an element(s) selected from the group consisting of Ti, Zr, Hf, V, Nb, Ta, Mo, W, Y, B and Si,
Z represents at least one kind of an element(s) selected from the group consisting of C, N and O,
d represents an atomic ratio of an Al element based on a total of the Al element, a Cr element and an L element,
e represents an atomic ratio of a Cr element based on a total of an Al element, the Cr element and an L element,
f represents an atomic ratio of an L element based on a total of an Al element, a Cr element and the L element,
d, e and f each satisfy 0.25≦d≦0.70, 0.30≦e≦0.75, 0≦f<0.20 and d+e+f=1, and
an average layer thickness of the coarse grain layer being 0.2 to 10 μm.

10. The coated cutting tool according to claim 9 , wherein d, e and f each satisfy 0.40≦d≦0.70, 0.30≦e≦0.50, 0≦f≦0.20, d≧e and d+e+f=1.

11. The coated cutting tool according to claim 9 , wherein Z of the coarse grain layer represents N.

12. The coated cutting tool according to claim 9 , wherein an average grain diameter Lx of the coarse grain layer measured at a direction parallel to an interface between the coating layer and the substrate is in the range of 400 nm to 1,000 nm.

13. The coated cutting tool according to claim 9 , wherein the coarse grain layer is cubic.

14. The coated cutting tool according to claim 13 , wherein a full width at half maximum intensity (FWHM) of an X-ray diffraction peak at a ( 200 ) plane of the coarse grain layer is 0.6° or less.

15. The coated cutting tool according to claim 9 , wherein the coating layer contains a lower layer formed on a surface of the substrate and a coarse grain layer formed on a surface of the lower layer, and the lower layer is a single layer or a multilayer containing at least one kind of a material(s) selected from
a metal containing at least one kind of metallic elements selected from the group consisting of Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, W, Y, Al and Si, and
a compound containing at least one kind of these metallic elements and at least one kind of nonmetallic elements selected from the group consisting of carbon, nitrogen, oxygen and boron.

16. The coated cutting tool according to claim 9 , wherein the coarse grain layer is an uppermost layer.

Assignees

• Tungaloy Corp

Inventors

• Kikuchi Masakazu

Classifications

• C01B33/00 Primary

  Silicon; Compounds thereof ({C01B6/00,} C01B21/00, C01B23/00 take precedence; persilicates C01B15/14; carbides C01B32/956) · CPC title

• C23C30/005

  on hard metal substrates · CPC title

• C23C30/00 Primary

  Coating with metallic material characterised only by the composition of the metallic material, i.e. not characterised by the coating process (C23C26/00, C23C28/00 take precedence) · CPC title

• C23C14/0664

  Carbonitrides · CPC title

• B23B2228/105

  with specified thickness · CPC title