Sintered compact and cutting tool

Patent metadata

Field	Value
Publication number	US-9988314-B2
Application number	US-201615327214-A
Country	US
Kind code	B2
Filing date	Feb 24, 2016
Priority date	May 29, 2015
Publication date	Jun 5, 2018
Grant date	Jun 5, 2018

Abstract

A sintered compact has a first material, a second material, and a third material. The first material is cubic boron nitride. The second material is a compound including zirconium. The third material is an aluminum oxide and the aluminum oxide includes a fine-particle aluminum oxide. The sintered compact has a first region in which not less than 5 volume % and not more than 50 volume % of the fine-particle aluminum oxide is dispersed in the second material. On arbitrary straight lines in the first region, an average value of continuous distances occupied by the fine-particle aluminum oxide is not more than 0.08 μm and a standard deviation of the continuous distances occupied by the fine-particle aluminum oxide is not more than 0.1 μm.

First claim

The invention claimed is:

1. A sintered compact comprising a first material, a second material, and a third material,
the first material being cubic boron nitride,
the second material being a compound including zirconium,
the third material being an aluminum oxide,
the aluminum oxide including a fine-particle aluminum oxide,
the sintered compact having a first region in which not less than 5 volume % and not more than 50 volume % of the fine-particle aluminum oxide is dispersed in the second material,
on arbitrary straight lines in the first region, an average value of continuous distances occupied by the fine-particle aluminum oxide being not more than 0.08 μm and a standard deviation of the continuous distances occupied by the fine-particle aluminum oxide being not more than 0.1 μm.

2. The sintered compact according to claim 1 , wherein on the arbitrary straight lines in the first region, the average value of continuous distances occupied by the fine-particle aluminum oxide is not less than 0.01 μm and not more than 0.05 μm and the standard deviation of the continuous distances occupied by the fine-particle aluminum oxide is not less than 0.01 μm and not more than 0.05 μm.

3. The sintered compact according to claim 1 , wherein in the first region, not less than 15 volume % and not more than 40 volume % of the fine-particle aluminum oxide is dispersed in the second material.

4. The sintered compact according to claim 1 , wherein not less than 20 volume % and not more than 80 volume % of the first material is included in the sintered compact.

5. The sintered compact according to claim 1 , wherein not less than 30 volume % and not more than 60 volume % of the first material is included in the sintered compact.

6. The sintered compact according to claim 1 , further comprising a fourth material, wherein the fourth material is at least one selected from a group consisting of magnesium oxide, cerium oxide, yttrium oxide, and hafnium oxide.

7. The sintered compact according to claim 1 , further comprising a fifth material, wherein the fifth material is at least one compound composed of (i) at least one element selected from a group consisting of a group 4 element, a group 5 element, a group 6 element in a periodic table, Al, and Si, and (ii) at least one element selected from a group consisting of carbon, nitrogen, and boron.

8. A cutting tool comprising the sintered compact recited in claim 1 .

Assignees

• Sumitomo Electric Hardmetal Corp
• Sumitomo Electric Industries

Inventors

• Danda Mayu
• Okamura Katsumi
• Kukino Satoru

Classifications

• C04B35/5831 Primary

  based on cubic boron nitrides {or Wurtzitic boron nitrides, including crystal structure transformation of powder} · CPC title

• B23C5/20

  with removable cutter bits or teeth {or cutting inserts} · CPC title

• C04B2235/3217

  Aluminum oxide or oxide forming salts thereof, e.g. bauxite, alpha-alumina · CPC title

• C04B2235/5436

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

• C04B2235/3225

  Yttrium oxide or oxide-forming salts thereof · CPC title