Abstract
In this article, synthesis of cubic boron nitride (cBN) sintered bodies without any additive was reviewed. At pressures higher than 8 GPa, direct transformation from hexagonal BN (hBN) to cBN took place near 2000°C. The resultant binderless cBN sintered bodies exhibit superior properties as highly wear resistive materials. At 10 GPa region, reaction temperature required for the complete transformation from hBN to cBN can be suppressed to near 1700°C, resulting in suppression of grain growth during the sintering. Higher wear resistance properties of binderless cBN sintered bodies with finer grains as cutting tools were demonstrated by their superior cutting performance against ferrous materials. Further requirement for the fabrication of large scale binderless cBN sintered bodies by sintering of fine cBN grains was also discussed for future study.
