论文部分内容阅读
用Mg和Mg_3N_2作触媒,以LiH作添加剂,在55—64千巴及1700—2100℃的高温高压下,进行了由六方氮化硼到立方氮化硼的合成。对合成晶体作了结构与有关性能的鉴定和测试。晶体表面上杂质、缺陷、生长中心和台阶结构的显微观察表明,高温高压下合成的立方氮化硼晶体具有通常条件下晶体生长的一般特征。对密切依赖于温度、压力状况及触媒组装的合成结果进行了分析和讨论。文中特别报道了触媒中少量LiH的加入对提高晶体粒度和质量的显著效果,其中获得了1毫米以上的大颗粒立方氮化硼晶体。
Using Mg and Mg_3N_2 as catalyst and LiH as additive, the synthesis of hexagonal boron nitride to cubic boron nitride was carried out under the high temperature and pressure of 55-64 kPa and 1700-2100 ℃. Synthetic crystal made of the structure and related performance identification and testing. Microscopic observations of impurities, defects, growth centers and step structures on the crystal surface indicate that cubic boron nitride crystals synthesized at high temperature and pressure have the general characteristics of crystal growth under normal conditions. The results of synthesis closely dependent on temperature, pressure conditions and catalyst assembly were analyzed and discussed. Especially reported in the catalyst a small amount of LiH added to improve the crystal size and quality of the significant effect, which obtained more than 1 mm of large particles of cubic boron nitride crystals.