Coated cutting tool

Patent metadata

Field	Value
Publication number	US-11224921-B2
Application number	US-201816630934-A
Country	US
Kind code	B2
Filing date	Sep 19, 2018
Priority date	Sep 27, 2017
Publication date	Jan 18, 2022
Grant date	Jan 18, 2022

Abstract

Provided is a coated cutting tool that has a nitride hard coating that contains Ti at 70 at % to 95 at % and Si at 5 at % to 30 at % with respect to the total amount of metallic elements, and Ar at 0.05 at % to 0.20 at % with respect to the total amount of metallic and non-metallic elements, has a NaCl-type crystalline structure, exhibits maximum diffraction peak intensity in the (200) plane, and has an average grain size of 5 nm to 30 nm. When 100 at % is defined as the total of content rates of the metallic elements, nitrogen, oxygen, and carbon in a composition at intervals of 20 nm from a depth of 20 nm to 200 nm from a surface of the hard coating, the content rate of nitrogen is 50.0 at % or more.

First claim

The invention claimed is:

1. A coated cutting tool having a hard coating on a surface thereof,
wherein the hard coating is a nitride, contains titanium (Ti) at 70 at % or more and 95 at % or less and silicon (Si) at 5 at % or more and 30 at % or less with respect to a total amount of metallic elements (including metalloid elements), and argon (Ar) at 0.05 at % or more and 0.20 at % or less with respect to a total amount of metallic elements (including metalloid elements) and non-metallic elements,
the hard coating has a NaCl type crystal structure, exhibits maximum diffraction peak intensity in the (200) plane due to the NaCl type crystal structure, and has an average grain size of 5 nm or more and 30 nm or less,
when 100 at % is defined as a total of content rates of metallic elements (including metalloid elements), nitrogen, oxygen, and carbon in a composition at intervals of 20 nm from a depth of 20 nm to a depth of 200 nm from the surface of the hard coating, the content rate of nitrogen is 50.0 at % or more, and
a flank of the coated cutting tool has an arithmetic mean height (Sa) of 0.1 μm or less, a maximum height (Sz) of 2.0 μm or less, and an arithmetic mean peak curvature (Spc) (1/mm) value of 5,000 or less, all of which are as defined by ISO 25178.

2. The coated cutting tool according to claim 1 , wherein the flank does not have nearly parallel grinding marks formed in a constant direction.

3. The coated cutting tool according to claim 1 , wherein an intermediate coating is provided between the tool and the hard coating.

4. The coated cutting tool according to claim 1 , wherein a value of skewness (Ssk) as defined by ISO 25178 is 4.0 or more and 0 or less in the flank.

5. The coated cutting tool according to claim 2 , wherein an intermediate coating is provided between the tool and the hard coating.

6. The coated cutting tool according to claim 2 , wherein a value of skewness (Ssk) as defined by ISO 25178 is 4.0 or more and 0 or less in the flank.

7. The coated cutting tool according to claim 3 , wherein a value of skewness (Ssk) as defined by ISO 25178 is −4.0 or more and 0 or less in the flank.

8. The coated cutting tool according to claim 5 , wherein a value of skewness (Ssk) as defined by ISO 25178 is −4.0 or more and 0 or less in the flank.

Assignees

• Mitsubishi Hitachi Tool Eng Ltd
• Moldino Tool Engineering Ltd

Inventors

• Sasaki Tomoya

Classifications

• C23C28/042

  including a refractory ceramic layer, e.g. refractory metal oxides, ZrO2, rare earth oxides · CPC title

• C23C14/34

  Sputtering · CPC title

• B23B2228/10

  Coatings · CPC title

• B23B27/14 Primary

  Cutting tools of which the bits or tips {or cutting inserts} are of special material · CPC title

• B23D43/00

  Broaching tools (for cutting gear teeth B23F21/26) · CPC title