天然石墨特征对合成金刚石性能影响的研究

Characteristics of natural graphite when used for synthesizing diamond

金刚石合成工业中所用天然石墨应具有极低灰分,同时杂质的种类、含量及状态都是影响金刚石品质的重要因素。本文结合对天然石墨原矿、高纯石墨及由其合成的金刚石进行了光学显微镜、X射线粉末衍射(XRD)、碳硫分析仪、场发射环境扫描电子显微镜(FESEM)和电子能谱(EDX)等测试分析,研究了天然鳞片石墨作为合成金刚石碳源的特点,认为天然鳞片石墨纯度、粒度以及杂质硫元素等对合成金刚石特征和性能有重要影响。

Natural graphite is one of the most important raw materials in diamond synthesis. Besides strict requirment on the degree of graphitization and particle size of the graphite as well as the ash content which should be extra-low, variety and state of impurities are critical influencing factors upon diamond quality. With optical microscope, X-ray powder diffraction, Environmental Scanning Electron Microscopy, Energy Dispersive X-ray Detector and high frequency IR carbon sulfur analyzer, graphite ore, high purity graphite and diamond synthesized from the high purity graphite were analyzed. The properties of graphite used as carbon source in diamond synthesis were discussed in thepresent paper. We suggest that performance of synthetic diamond was dependant on the purity, particle size and impurity of natural graphite.