优质金黄色工业金刚石的高温高压合成

Synthesis of golden industrial diamonds by HPHT

在铁基触媒中引入添加剂,利用高温高压法,成功地合成了金黄色的工业金刚石。研究发现,随着添加剂含量的提高,合成金刚石的最低压力和某确定压力下的最低生长温度都呈增加趋势。另外,这种添加剂对金刚石的自发成核有一定的抑制作用,而且随其添加量的逐渐增加,这种抑制作用逐渐增强。在光学显微镜下进行观察,发现所合成的晶体呈完整的八面体形状,包裹体少,透明度高,优晶率达到80%以上。通过与无添加剂样品合成的金刚石进行对比,发现两种情况下所合成的晶体生长速度相近,晶体形貌相似,只是前者表面的凹坑呈三角形,而后者表面的凹坑呈圆形。

The golden industrial diamonds had been successfully synthesized using ironbased powder catalyst containing additive by high pressure and high temperature （HPHT） method. With the increase of additive content, the minimum pressure and the minimum temperature at certain pressure for diamond formation tended to rise. It was also found that the additive had inhibited the spontaneous nucleation of diamond to a certain extent. And with the increase of additive content in the system, the inhibitory effect became more and more significant. Under optical microscope, it was observed that the synthetic diamonds were of integrated octahedral shape, high transparency, and with little inclusions. The excellent rate is above 80%. Compared with the diamonds synthesized from no-additive system, both of them were of octahedral shape, with approximate growth rate. The pits on the crystal surface of the former were triangular, while those of latter were round in shape.