经不同温度退火处理的纳米纤锌矿氮化硼的结构变化及长大规律

CHANGE OF NANO-wBN IN STRUCTURE AND PARTICLE SIZE WITH TEMPERATURE

用冲击波法合成了纤锌矿氮化硼(wBN)超微粉,粉末X射线衍射(PXRD)和透射电子显微镜(TEM)的研究指出:所合成的wBN是由尺寸为10—100nm的薄片状微晶构成,其平均尺寸约为16nm,同时发现随着样品退火温度的增加,颗粒尺寸缓慢长大.从500℃开始有较快的增长,晶形趋于完整,无结构上的变化.

In this paper, we investigate the changes of wBN ultrafine particles prepared by shock-wave method in structure and particle size with temperature by PXRD and TEM experiments. It is found that all wBN samples are of wurtzite structure, and the average particle size of the unheat-treated sample is about 16nm. The changes of structure of wBN heat-treated at 100,300,500,600 and 800℃ have not been observed, and the average particle size of wBN heat-treated below 500℃ is about 20nm, and that above this temperature exceeds 30nm.