CPC C04B 35/5831 (2013.01) [C04B 2235/3217 (2013.01); C04B 2235/386 (2013.01); C04B 2235/762 (2013.01); C04B 2235/781 (2013.01); C04B 2235/785 (2013.01)] | 5 Claims |
1. A cubic boron nitride sintered material comprising cubic boron nitride grains, a binder phase, and one or more first voids, wherein
a percentage on a volume basis of the cubic boron nitride grains based on the total of the cubic boron nitride grains and the binder phase is 40% by volume or more and 70% by volume or less,
a percentage on a volume basis of the binder phase based on the total of the cubic boron nitride grains and the binder phase is 30% by volume or more and 60% by volume or less,
the binder phase includes 10% by volume or more and 100% by volume or less of aluminum oxide grains based on the entire binder phase,
an average grain size of the aluminum oxide grains is 50 nm or more and 250 nm or less,
the cubic boron nitride sintered material comprises 0.001% by volume or more and 0.100% by volume or less of the one or more first voids, and
at least one portion of each of the one or more first voids is in contact with the aluminum oxide grains.
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