Patent ID: 11958782
Assignee: SUMITOMO ELECTRIC HARDMETAL CORP.
Field: Materials, metallurgy (Chemistry)
Classification: CPC C | IPC C

Claim 4:
5. The cubic boron nitride sintered material according to claim 1, wherein
the cubic boron nitride grains include first cubic boron nitride grains,
grain sizes of the first cubic boron nitride grains are each 5% or more and 50% or less of the average grain size of the aluminum oxide grains,
a percentage on a volume basis of the first cubic boron nitride grains relative to the binder phase is 1% or more and 30% or less,
the first cubic boron nitride grains include 30% or more and 100% or less of first A cubic boron nitride grains on a number basis, and
at least one portion of each of the first A cubic boron nitride grains is in contact with the aluminum oxide grains.