Brazing material for bonding; and composite part and cutting tool using same

Patent metadata

Field	Value
Publication number	US-10252379-B2
Application number	US-201415107632-A
Country	US
Kind code	B2
Filing date	Dec 22, 2014
Priority date	Dec 25, 2013
Publication date	Apr 9, 2019
Grant date	Apr 9, 2019

Abstract

A cutting tool including a cutting edge part made of cBN sintered material bonded through a brazing material for bonding and a cutting tool body made of WC-based cemented carbide is provided. In the cutting tool, the cutting edge part made of cBN sintered material and the cutting tool body made of WC-based cemented carbide are brazed by using a blazing material for bonding including: 35-40% of Ti in a mass ratio; 35-40% of Zr in a mass ratio; 5-15% of Ni in a mass ratio; and the Cu balance including inevitable impurities.

First claim

What is claimed is:

1. A composite part comprising:
a cemented carbide body; and
a cubic boron nitride sintered material bonded to the cemented carbide body through a bonding part, wherein
(a) the bonding part includes an interface layer having an average layer thickness of 0.5 μm to 5 μm, said interface layer being adjacent to the cubic boron nitride sintered material and containing 50 atomic % or more of Ti and 10 atomic % or more of N,
(b) the bonding part has needle crystal structure, which: contacts a cubic boron nitride grain constituting the cubic boron nitride sintered material; contains 50 atomic % or more of Ti, 10-30 atomic % of Zr, and 2-10 atomic % of B; and has 10-100 nm of an average width and 5 or more of an average aspect ratio, and
(c) the needle crystal structure has a length equal to or longer than a layer thickness of the interface layer, which is adjacent to the cubic boron nitride sintered material and contains at least Ti and N, and traverses the interface layer in a thickness direction.

2. A cutting tool with a cubic boron nitride sintered material comprising the composite part according to claim 1 , wherein the bonding part interposes between the cubic boron nitride material and a cutting tool body made of cemented carbide.

3. The composite part according to claim 1 , wherein
the bonding part further comprises a brazing material portion, which contains 35-40% of Ti in a mass ratio; 35-40% of Zr in a mass ratio; 5-15% of Ni in a mass ratio; and the Cu balance including inevitable impurities, and
the interface layer is formed between the cubic boron nitride sintered material and the brazing material portion.

Assignees

• Mitsubishi Materials Corp

Inventors

• Igarashi Makoto
• Ohashi Tadakazu
• Yumoto Kenji
• Shimizu Hiroyasu

Classifications

• C22C30/02

  containing copper · CPC title

• B23B2240/08

  Brazed connections · CPC title

• C22C14/00

  Alloys based on titanium · CPC title

• C22C2204/00

  End product comprising different layers, coatings or parts of cermet · CPC title

• B23B27/18

  with cutting bits or tips {or cutting inserts} rigidly mounted, e.g. by brazing · CPC title