Cubic boron nitride sintered body

Abstract

A cBN sintered body including cBN and a binder phase, wherein a content ratio of the cBN is 80 to 94 volume %, a content ratio of the binder phase is 6 to 20 volume %, the binder phase contains a metal phase, a V compound, and an Al compound, the metal phase contains one or more selected from the group consisting of Ni, and a Ni-containing alloy and solid solution, the Ni-containing alloy and solid solution each contain Ni and one or more elements selected from the group consisting of Al, Ti, V, Cr, Zr, Nb, Mo, Hf, Ta, W, and Co, the V compound contains one or more selected from the group consisting of VN, VCN, and VC, the Al compound contains one or more selected from the group consisting of Al 2 O 3 , AlN, and AlB 2 , a maximum peak position 2θ of a 200 plane of the metal phase is less than 51.60°, and I 1 /(I 1 +I 2 ) is 0.40 to 0.80, where I 1 denotes an X-ray diffraction peak intensity of a 220 plane of the V compound, and I 2 denotes an X-ray diffraction peak intensity of a 200 plane of the metal phase.

What is claimed is: 
     
         1 . A cubic boron nitride sintered body comprising cubic boron nitride and a binder phase, wherein
 a content ratio of the cubic boron nitride is 80 volume % or more and 94 volume % or less based on the total amount of the sintered body,   a content ratio of the binder phase is 6 volume % or more and 20 volume % or less based on the total amount of the sintered body,   the binder phase comprises a metal phase, a V compound, and an Al compound,   the metal phase comprises one or more selected from a group consisting of Ni metal, a Ni-containing alloy, and a Ni-containing solid solution,   the Ni-containing alloy and the Ni-containing solid solution each comprise Ni and one or more elements selected from a group consisting of Al, Ti, V, Cr, Zr, Nb, Mo, Hf, Ta, W, and Co,   the V compound comprises one or more selected from a group consisting of VN, VCN, and VC,   the Al compound comprises one or more selected from a group consisting of Al 2 O 3 , AlN, and AlB 2 ,   a maximum peak position 2θ (°) of a (200) plane of the metal phase in X-ray diffraction is less than 51.60°, and   I 1 /(I 1 +I 2 ) is 0.40 or more and 0.80 or less, where I 1  denotes an X-ray diffraction peak intensity of a (220) plane of the V compound, and I 2  denotes an X-ray diffraction peak intensity of the (200) plane of the metal phase.   
     
     
         2 . The cubic boron nitride sintered body according to  claim 1 , wherein a full width at half maximum (°) of a peak of the (200) plane of the metal phase in X-ray diffraction is 0.40° or more and 0.70° or less. 
     
     
         3 . The cubic boron nitride sintered body according to  claim 1 , wherein I 1 /I 3  is 0.70 or more and 1.50 or less, where I 3  denotes an X-ray diffraction peak intensity of the (220) plane of the cubic boron nitride. 
     
     
         4 . The cubic boron nitride sintered body according to  claim 1 , wherein a maximum peak position 2θ (°) of the (220) plane of the V compound in X-ray diffraction is less than 63.40°. 
     
     
         5 . The cubic boron nitride sintered body according to  claim 1 , wherein a maximum peak position 2θ (°) of the (200) plane of the metal phase in X-ray diffraction is less than 51.40°. 
     
     
         6 . The cubic boron nitride sintered body according to  claim 2 , wherein I 1 /I 3  is 0.70 or more and 1.50 or less, where I 3  denotes an X-ray diffraction peak intensity of the (220) plane of the cubic boron nitride. 
     
     
         7 . The cubic boron nitride sintered body according to  claim 2 , wherein a maximum peak position 2θ (°) of the (220) plane of the V compound in X-ray diffraction is less than 63.40°. 
     
     
         8 . The cubic boron nitride sintered body according to  claim 3 , wherein a maximum peak position 2θ (°) of the (220) plane of the V compound in X-ray diffraction is less than 63.40°. 
     
     
         9 . The cubic boron nitride sintered body according to  claim 6 , wherein a maximum peak position 2θ (°) of the (200) plane of the metal phase in X-ray diffraction is less than 51.40°. 
     
     
         10 . The cubic boron nitride sintered body according to  claim 2 , wherein a maximum peak position 2θ (°) of the (200) plane of the metal phase in X-ray diffraction is less than 51.40°. 
     
     
         11 . The cubic boron nitride sintered body according to  claim 3 , wherein a maximum peak position 2θ (°) of the (200) plane of the metal phase in X-ray diffraction is less than 51.40°. 
     
     
         12 . The cubic boron nitride sintered body according to  claim 4 , wherein a maximum peak position 2θ (°) of the (200) plane of the metal phase in X-ray diffraction is less than 51.40°. 
     
     
         13 . The cubic boron nitride sintered body according to  claim 6 , wherein a maximum peak position 2θ (°) of the (220) plane of the V compound in X-ray diffraction is less than 63.40°. 
     
     
         14 . The cubic boron nitride sintered body according to  claim 7 , wherein a maximum peak position 2θ (°) of the (200) plane of the metal phase in X-ray diffraction is less than 51.40°. 
     
     
         15 . The cubic boron nitride sintered body according to  claim 8 , wherein a maximum peak position 2θ (°) of the (200) plane of the metal phase in X-ray diffraction is less than 51.40°. 
     
     
         16 . The cubic boron nitride sintered body according to  claim 13 , wherein a maximum peak position 2θ (°) of the (200) plane of the metal phase in X-ray diffraction is less than 51.40°.