Cubic boron nitride sintered body and cutting tool

Patent metadata

Field	Value
Publication number	US-10124413-B2
Application number	US-201515313815-A
Country	US
Kind code	B2
Filing date	Jun 26, 2015
Priority date	Jun 27, 2014
Publication date	Nov 13, 2018
Grant date	Nov 13, 2018

Abstract

A cBN sintered body contains cBN particles whose proportion is 85-97% by volume, and a binding phase whose proportion is 3-15% by volume. The cBN sintered body contains Al whose ratio to the entirety of the cBN sintered body is 0.1-5% by mass, and Co whose mass ratio to the Al is 3 to 40, and includes Al 3 B 6 Co 20 .

First claim

The invention claimed is:

1. A cBN sintered body, comprising:
cBN particles whose proportion is 85-97% by volume; and
a binding phase whose proportion is 3-15% by volume,
wherein an Al content in the cBN sintered body is 0.1-5% by mass,
wherein a ratio of a Co content to the Al content (Co/Al) is 3 to 40 in terms of mass ratio, and
wherein the cBN sintered body includes Al 3 B 6 Co 20 .

2. The cBN sintered body according to claim 1 , wherein a ratio of peak strength of a strongest peak of the Al 3 B 6 Co 20 to peak strength of cBN (111) is 0.02-0.25 in an X-ray diffraction measurement.

3. The cBN sintered body according to claim 1 , wherein a ratio of peak strength of a strongest peak of the Al 3 B 6 Co 20 to peak strength of Co (200) is 0.01-0.25 in an X-ray diffraction measurement.

4. The cBN sintered body according to claim 1 , wherein a ratio of peak strength of the Co (200) to peak strength of cBN (111) is 0.5-3 in an X-ray diffraction measurement.

5. The cBN sintered body according to claim 1 , wherein no peak of AlN exists, or a ratio of peak strength of a strongest peak of AlN to peak strength of cBN (111) is 0.05 or less in an X-ray diffraction measurement.

6. The cBN sintered body according to claim 1 , wherein no peak of BCo exists, or a ratio of peak strength of a strongest peak of BCo to peak strength of cBN (111) is 0.05 or less in an X-ray diffraction measurement.

7. The cBN sintered body according to claim 1 , wherein a mean particle size of the cBN particles is 1.5-2.5 μm and a mean particle size of Al 3 B 6 Co 20 particles is 0.02-0.5 μm.

8. A cutting tool, comprising a cutting edge part composed of the cBN sintered body according to claim 1 .

Assignees

• Kyocera Corp

Inventors

• Hirosaki Kouji

Classifications

• C04B2235/405

  Iron group metals · CPC title

• C04B2235/6567

  Treatment time · CPC title

• C04B2235/786

  Micrometer sized grains, i.e. from 1 to 100 micron · CPC title

• C04B35/6303 Primary

  Inorganic additives · CPC title

• C04B2235/6022

  Injection moulding · CPC title