Si-C-SiO_2体系在高压变质条件下的结构相变

Study on the structure transition of graphite and quartz mixed by silicon under high temperature and high pressure

根据高能机械球磨与地球板块间的碰撞具有的碰撞局域性和剪切应力的相似特点,采用高能机械球磨与静高温、高压技术,按照质量比m(Si):m(C):m(SiO2)=65∶14∶21制成样品,人工合成柯石英.用X射线粉末衍射对经高能机械球磨后的样品进行了结构表征.结果表明:得到合成柯石英的最低条件是3.8 GPa和873K;合成的柯石英为单斜柯石英,与天然矿物中发现的柯石英晶体的结构相同.

A new laboratory method for synthesizing coesite in the earth＇s crust by considering the similarity characteristics of local collisions and shearing strength between the earth＇s plates and the highenergy mechanical ball milling （MBM）,combining the high energy MBM and high static pressure and high temperature technique, and using mixtures of α-quartz and graphite as the initial material, silicon is mixed by the suitest quality rate. A Raman spectrum of synthetic eoesite with the most peaks has been obtained by the method of the present paper. The lowest pressure and high temperature for synthesizing coesite are 3.8 GPa,873K.