Ceramic sintered body
A ceramic sintered body containing aluminum oxide, tungsten carbide and zirconium oxide, wherein: the zirconium oxide contains ZrO and ZrO 2 ; the ZrO 2 has a crystal structure or structures of one or two kinds selected from the group consisting of a tetragonal crystal structure and a cubic crystal structure; and when, in X-ray diffraction, regarding a peak intensity for a (111) plane of the ZrO as being denoted by I 1 , regarding a peak intensity for a (101) plane of ZrO 2 having a tetragonal crystal structure as being denoted by I 2t , and also regarding a peak intensity for a (111) plane of ZrO 2 having a cubic crystal structure as being denoted by I 2c , a ratio of I 1 based on a total of I 1 , I 2t and I 2c [I 1 /(I 1 +I 2t +I 2c )] is from 0.05 or more to 0.90 or less.
1. A ceramic sintered body containing aluminum oxide, tungsten carbide and zirconium oxide, wherein:
the zirconium oxide contains ZrO and ZrO 2 ;
the ZrO 2 has a crystal structure or structures of one or two kinds selected from the group consisting of a tetragonal crystal structure and a cubic crystal structure;
based on a total content of the ceramic sintered body:
a content of the aluminum oxide is from 30 volume % or more to 74 volume % or less;
a content of the tungsten carbide is from 25 volume % or more to 69 volume % or less; and
a content of the zirconium oxide is from 1 volume % or more to 20 volume % or less; and
when, in X-ray diffraction, regarding a peak intensity for a (111) plane of the ZrO as being denoted by I 1 , regarding a peak intensity for a (101) plane of ZrO 2 having a tetragonal crystal structure as being denoted by I 2t , and also regarding a peak intensity for a (111) plane of ZrO 2 having a cubic crystal structure as being denoted by I 2c , a ratio of I 1 based on a total of I 1 , I 2t and I 2c [I 1 /(I 1 +I 2t +I 2c )] is from 0.05 or more to 0.90 or less.
2. The ceramic sintered body according to claim 1 , wherein the ratio of I 1 based on a total of I 1 , I 2t and I 2c [I 1 /(I 1 +I 2t +I 2c )] is from 0.20 or more to 0.80 or less.
3. The ceramic sintered body according to claim 1 , wherein:
the aluminum oxide is α-type aluminum oxide; and
when, in X-ray diffraction, regarding a peak intensity for a (110) plane of the α-type aluminum oxide as being denoted by I 3 , a ratio of a total of I 2t and I 2c based on I 3 [(I 2t +I 2c )/I 3 ] is from 0.30 or more to 4.00 or less.
4. The ceramic sintered body according to claim 1 , wherein an average particle size of the aluminum oxide is from 0.20 μm or more to 2.00 μm or less.
5. The ceramic sintered body according to claim 1 , wherein an average particle size of the tungsten carbide is from 0.10 μm or more to 1.50 μm or less.
6. The ceramic sintered body according to claim 2 , wherein:
the aluminum oxide is α-type aluminum oxide; and
when, in X-ray diffraction, regarding a peak intensity for a (110) plane of the α-type aluminum oxide as being denoted by I 3 , a ratio of a total of I 2t and I 2c based on I 3 [(I 2t +I 2c )/I 3 ] is from 0.30 or more to 4.00 or less.
7. The ceramic sintered body according to claim 6 , wherein an average particle size of the aluminum oxide is from 0.20 μm or more to 2.00 μm or less.
8. The ceramic sintered body according to claim 2 , wherein an average particle size of the aluminum oxide is from 0.20 μm or more to 2.00 μm or less.
9. The ceramic sintered body according to claim 3 , wherein an average particle size of the aluminum oxide is from 0.20 μm or more to 2.00 μm or less.
10. The ceramic sintered body according to claim 2 , wherein an average particle size of the tungsten carbide is from 0.10 μm or more to 1.50 μm or less.
11. The ceramic sintered body according to claim 3 , wherein an average particle size of the tungsten carbide is from 0.10 μm or more to 1.50 μm or less.
12. The ceramic sintered body according to claim 4 , wherein an average particle size of the tungsten carbide is from 0.10 μm or more to 1.50 μm or less.