US 12,410,102 B2
CBN sintered body and cutting tool
Masashi Momma, Tokyo (JP); Shiro Oguchi, Tokyo (JP); Ryota Takei, Yashio (JP); and Kenji Yumoto, Tokyo (JP)
Assigned to MITSUBISHI MATERIALS CORPORATION, Tokyo (JP)
Appl. No. 17/433,275
Filed by MITSUBISHI MATERIALS CORPORATION, Tokyo (JP)
PCT Filed Feb. 27, 2020, PCT No. PCT/JP2020/007904
§ 371(c)(1), (2) Date Aug. 24, 2021,
PCT Pub. No. WO2020/175598, PCT Pub. Date Sep. 3, 2020.
Claims priority of application No. 2019-034794 (JP), filed on Feb. 27, 2019.
Prior Publication US 2022/0144709 A1, May 12, 2022
Int. Cl. C04B 35/5831 (2006.01); B23B 27/14 (2006.01)
CPC C04B 35/5831 (2013.01) [B23B 27/148 (2013.01); B23B 2226/125 (2013.01); C04B 2235/3843 (2013.01); C04B 2235/3856 (2013.01); C04B 2235/386 (2013.01); C04B 2235/3886 (2013.01); C04B 2235/404 (2013.01)] 5 Claims
OG exemplary drawing
 
1. A cBN-based ultra-high pressure sintered body comprising:
cBN particles; and
a binder phase,
wherein the binder phase contains at least one of a nitride or oxide of Al or a nitride, carbide, or carbonitride of Ti, and includes a metal boride having an average particle diameter of 20 to 300 nm, and the metal boride is dispersed in an amount of 0.1 to 5.0 vol % with respect to the whole cBN sintered body,
the metal boride includes a metal boride (B) containing at least one of Nb, Ta, Cr, Mo, and W as a metal component and containing no Ti and a metal boride (A) containing only Ti as a metal component,
in a case where a ratio (vol %) of the metal boride (A) containing only Ti as a metal component is represented by Va and a ratio (vol %) of the metal boride (B) containing at least one of Nb, Ta, Cr, Mo, and W as a metal component and containing no Ti is represented by Vb, a ratio of Vb/Va is 0.1 to 1.0, and
a content ratio of the cBN particles in the cBN-based ultra-high pressure sintered body is 40 to 80 vol %, and assuming that a content ratio of all the cBN particles is 100 vol %, a content ratio of the cBN particles having an average particle diameter of less than 2 μm is 5 to 40 vol %, and a content ratio of the cBN particles having an average particle diameter of 2 μm or greater and less than 8 μm is 60 to 95 vol %.