| 摘要 |
PROBLEM TO BE SOLVED: To obtain a cubic boron nitride sintered compact having satisfactory strength, hardness, heat resistance and heat radiating property as a cutting tool. SOLUTION: When low pressure phase boron nitride is simultaneously subjected to direct conversion and sintering at high temp. and pressure to produce a cubic boron nitride sintered compact, the low pressure phase boron nitride is prepd. as starting material by reducing a compd. contg. boron and oxygen with a compd. contg. nitrogen and carbon. The ratio (I220 /I111 ) of the X-ray diffraction intensity I220 of each (220) plane of the resultant cubic boron nitride sintered compact to the X-ray diffraction intensity I111 of each (111) plane is >=0.1. |
