Cubic boron nitride complex polycrystal and manufacturing method therefor, and cutting tool, wire-drawing die and grinding tool

Patent metadata

Field	Value
Publication number	US-9416304-B2
Application number	US-201214241362-A
Country	US
Kind code	B2
Filing date	Aug 24, 2012
Priority date	Aug 30, 2011
Publication date	Aug 16, 2016
Grant date	Aug 16, 2016

Abstract

A cubic boron nitride complex polycrystal contains granular cubic boron nitride and tabular cubic boron nitride. The average grain size of the granular cubic boron nitride is 500 nm or less. The maximum value of a short side of the tabular cubic boron nitride is 10 nm or more to 10000 nm or less. Thereby, it is possible to provide a cubic boron nitride complex polycrystal having high hardness and a manufacturing method therefor, a cutting tool, a wire-drawing die and a grinding tool including the same.

First claim

The invention claimed is:

1. A cubic boron nitride complex polycrystal comprising:
granular cubic boron nitride; and
tabular cubic boron nitride;
the average grain size of said granular cubic boron nitride being 500 nm or less, and
the maximum value of a short side of said tabular cubic boron nitride being 10 nm or more to 10000 nm or less.

2. The cubic boron nitride complex polycrystal according to claim 1 , wherein the average grain size of said granular cubic boron nitride is 300 nm or less.

3. The cubic boron nitride complex polycrystal according to claim 1 , wherein the maximum value of said short side of said tabular cubic boron nitride is 10 nm or more to 1000 nm or less.

4. The cubic boron nitride complex polycrystal according to claim 1 , further comprising wurtzite-type boron nitride and unavoidable impurities as the remainder, wherein
the content of said wurtzite-type boron nitride is 0.1 to 95 v/v %.

5. The cubic boron nitride complex polycrystal according to claim 4 , wherein said content of said wurtzite-type boron nitride is 0.1 to 10 v/v %.

6. The cubic boron nitride complex polycrystal according to claim 4 , wherein the average grain size of said granular cubic boron nitride is 200 nm or less.

7. The cubic boron nitride complex polycrystal according to claim 1 , further comprising wurtzite-type boron nitride, pressurized hexagonal boron nitride and unavoidable impurities as the remainder, wherein
the content of said wurtzite-type boron nitride is 0.1 to 3 v/v %, and
the content of said pressurized hexagonal boron nitride is 0.01 to 0.5 v/v %.

8. A cutting tool including the cubic boron nitride complex polycrystal according to claim 1 .

9. A wire-drawing die including the cubic boron nitride complex polycrystal according to claim 1 .

10. A grinding tool including the cubic boron nitride complex polycrystal according to claim 1 .

11. The cubic boron nitride complex polycrystal according to claim 1 , wherein the tabular cubic boron nitride is stacked in layers.

Assignees

• Ishida Yuh
• Sumiya Hitoshi
• Sumitomo Electric Industries

Inventors

• Ishida Yuh
• Sumiya Hitoshi

Classifications

• C04B2235/72

  Products characterised by the absence or the low content of specific components, e.g. alkali metal free alumina ceramics · CPC title

• C04B35/5831 Primary

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

• C04B2235/767

  Hexagonal symmetry, e.g. beta-Si3N4, beta-Sialon, alpha-SiC or hexa-ferrites · CPC title

• C04B2235/781

  Nanograined materials, i.e. having grain sizes below 100 nm · CPC title

• C09K3/1418 Primary

  obtained by division of a mass agglomerated by sintering · CPC title