US 12,454,014 B1
Cemented carbide and cutting tool
Takahiro Yamakawa, Itami (JP); Takato Yamanishi, Itami (JP); and Masahito Hikiji, Itami (JP)
Assigned to SUMITOMO ELECTRIC HARDMETAL CORP., Itami (JP)
Appl. No. 19/100,942
Filed by SUMITOMO ELECTRIC HARDMETAL CORP., Itami (JP)
PCT Filed Jun. 18, 2024, PCT No. PCT/JP2024/022000
§ 371(c)(1), (2) Date Feb. 4, 2025,
.
Int. Cl. B23B 27/14 (2006.01); C22C 29/08 (2006.01)
CPC B23B 27/148 (2013.01) [C22C 29/08 (2013.01); B23B 2222/28 (2013.01); B23B 2222/92 (2013.01)] 6 Claims
OG exemplary drawing
 
1. A cemented carbide comprising a first phase and a second phase, wherein
the first phase consists of a plurality of tungsten carbide grains,
a content ratio of the first phase of the cemented carbide is 65 volume % or more and 85 volume % or less,
a content ratio of the second phase of the cemented carbide is 4 volume % or more and 25 volume % or less,
the second phase includes 50 mass % or more of cobalt,
the second phase includes zirconium,
a cobalt content ratio MCo of the cemented carbide is 3 mass % or more and 15 mass % or less,
a and b of the cemented carbide indicate a relation of the following formula I:
b<0.0485a+0.0001  Formula I, where
the a represents a percentage, (MZr/MCo)×100, of a zirconium content ratio MZr of the cemented carbide in mass % with respect to the cobalt content ratio MCo of the cemented carbide in mass %,
the a is more than 0 and 8 or less,
the b represents an area percentage of pore in a first region of a cross section of the cemented carbide, and
the first region is a region located within a distance of 50 μm from a surface of the cemented carbide in the cross section.