摘要
本文用B2O3和单质B作为B源分别与Li3N作用,通过化学反应在低于Li3N-hBN体系合成CBN件下合成出了CBN晶体。在上述反应中最低合成条件分别为4.0 GPa-1400℃和4.5 GPa-1450℃。由于初始材料中不含BN,所以CBN晶体成核方式为化合物之间或化合物与单质间的化学键重组直接成核而非传统的从sp2杂化的hBN向sp3杂化的CBN相转化过程。实验证明,化学键重组成核所需能量要小于相转化成核所需能量。利用含有硼、氮原子的化合物之间在高温高压下的化学反应直接成核是制备CBN晶体的有效方法。
Cubic boron nitride single crystal was synthesized by chemical reactions between compounds B2O3 or element B and Li3N under high pressure and high temperature （HPHT）. The lowest reaction conditions in the two reaction systems were 4.0 GPa - 1400℃ and 4.5 GPa - 1450℃ respectively,and the conditions of CBN formation are obviously lower than that in Li3N - hBN system, Because there is not any BN in the starting materials ,the nucleation of CBN crystal was not the phase transition from sp^2 -bonded hBN to sp^3 -bonded CBN as in the Li3N -hBN system,but was directly formed by chemical reactions. Experiment results show that the nucleation energy by bond restructuring was lower than that of CBN spontaneous nucleation in Li3N - hBN system. It is an effective method in which the chemical reactions between contained B and N atom compounds was used to synthesize CBN crystals under HPHT.
出处
《金刚石与磨料磨具工程》
CAS
北大核心
2007年第4期25-26,31,共3页
Diamond & Abrasives Engineering
基金
国家自然科学基金资助项目(60176009)
关键词
HPHT
化学反应
直接成核
CBN
HPHT
chemical reaction
nucleated directly
cubic boron nitride
