金刚石合成时形成的镍基金属包膜和溶媒的组织结构

MICROSTRUCTURES OF NI-BASED METAL FILM SURROUNDING DIAMOND AND SOLVENT METAL

利用扫描电镜和透射电镜观察了金刚石合成时形成的镍基金属包膜和溶媒的组织结构。结果表明,与包膜相比,溶媒合金内含有块状的未溶石墨和较多的球状再结晶石墨。包膜与溶媒的相结构均由溶入了锰、钴的镍基γ固溶体和石墨组成。包膜内没有发现金刚石结构的事实说明,金刚石单晶不是在高温高压下的包膜内熔体内完成转变的。高温高压下使包膜熔体内的碳转变为金刚石的催化相是γ固溶体。

Microstructures of the solvent meatal and Ni-based metal film surrounding diamond, formed during diamond synthesis, was investigated using scanning electron microscopy and transmission electron microscopy. The results show that there exist chunk graphite and more globoid re-crystal graphite in the solvent metal than that in the film. All the phases in the film and the solvent metal are only composed of Ni-Mn-Co-C solid solution (γ-phase) and graphite. Diamond structure was not found in the film, which should suggest that the diamond formation could not be finished in the film at high temperature and high pressure(HTHP). The phase catalyzing carbon into diamond in the film at HTHP may be the γ-phase.