摘要
天然石墨是金刚石合成的主要原料,其质量对合成金刚石的品质有很大影响。采用一种无硫碳石墨的制备方法,用H2O2等除硫剂,制备高纯无硫天然石墨,以其为碳源,采用静压粉末触媒法在中国产六面顶压机上高温高压合成金刚石。利用光学显微镜、扫描电子显微镜等观察合成金刚石的形貌特征,合成金刚石以粒径>0.325 mm的粗粒为主,0.325～0.700 mm的颗粒占80%,但是,粒度超过0.700 mm的颗粒以晶簇为主。结合X射线衍射仪、激光拉曼光谱仪等手段分析了合成金刚石的微结构,认为合成金刚石结晶度高、结构完整。实验结果表明,高纯无硫高石墨化度的天然石墨用做碳源,有利于金刚石合成,金刚石晶体成核率高、结晶程度高、晶形好、颗粒大。以高纯无硫天然鳞片石墨为碳源,通过调节合成条件,能够有效制备出优质粗粒度金刚石。
Natural graphite is one of the most important raw materials in diamond synthesis,and the purity of graphite is a main factor to affect the quality of diamond.Graphite was purified by H2O2,a new patent method to produce graphite without sulfur content,and used as carbon source to synthesize diamond.The resultant diamond particles were characterized by optical microscopy,scanning electron microscopy(SEM),in which,the most diamond particles,about 80 %,were single diamond crystals with the diameter between 0.325 and 0.700 mm,but main drusy crystal for large particles with the diameter above 0.700 mm.By means of analysis of X-ray diffractometry(XRD) and laser Raman spectroscopy(RS),the resultant diamond particles were found well crystallized with perfect structure.By using graphite with high purity and high graphitization as carbon source,the synthetic diamonds can be nucleated easily and grown up quickly.High quality diamond crystals with large particle size can be produced with the high purity flake graphite without sulfur at suitable synthesizing conditions.
出处
《金刚石与磨料磨具工程》
CAS
2012年第4期1-5,9,共6页
Diamond & Abrasives Engineering
基金
国家自然科学基金资助项目(No.40972027)
关键词
天然石墨
硫
金刚石
碳源
natural graphite
sulfur
diamond
carbon source
