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为了探明从ＳｉＣ生成金刚石这一过程中触媒作用的机理，有必要调查ＳｉＣ加不同金属在高压高温下的行为。在本工作中，以１６重量比混合的ＳｉＣ和铁粉经５．４～６．０ＧＰａ的高压力和１３００～１５００℃的高温处理２０ｍｉｎ后，样品的Ｘ射线衍射分析表明：所有实验条件下ＳｉＣ都发生了分解，并分别生成了Ｆｅ３Ｓｉ和Ｆｅ３Ｃ；温度越高，ＳｉＣ分解得越彻底，在温度高于１３７５℃的样品中，伴随Ｆｅ３Ｃ减少，有金刚石和石墨明显析出。扫描电镜观察表明：６．０ＧＰａ、１５００℃下所得的金刚石晶体具有完整的八面体晶形，平均粒度约５０μｍ。
In order to find out the mechanism of catalytic action in the process of diamond formation from SiC, it is necessary to investigate the behavior of SiC plus different metals under high pressure and temperature. In this work, X-ray diffraction analysis of SiC and iron powder mixed by 16 weight ratio under the high pressure of 5.4 ~ 6.0GPa and the high temperature of 1300 ~ 1500 ℃ for 20min showed that under all experimental conditions, SiC Both decomposed and formed Fe3Si and Fe3C respectively. The higher the temperature, the more thoroughly the SiC decomposed. In the samples with the temperature higher than 1375 ° C, diamond and graphite were obviously precipitated with the decrease of Fe3C. Scanning electron microscopy showed that the diamond crystals obtained at 6.0GPa and 1500 ℃ had a complete octahedral crystal shape with an average particle size of about 50μm.