金刚石合成叶蜡石腔体不同区域相结构计算分析  

Semi-quantitative analysis of phase structure of pyrophyllite used for diamond synthesis under HT/HP

作　　者：邓福铭[1] 赵国强[1] 陈为芳[1] 王强[1] 张丹[1] 

机构地区：[1]中国矿业大学(北京)超硬刀具材料研究所,北京100083

出　　处：《超硬材料工程》2011年第2期15-18,共4页Superhard Material Engineering

基　　金：国家自然科学基金(No.50974124)

摘　　要：选取高温高压合成金刚石后的固体密封传压介质叶蜡石为研究对象,将WC顶锤与白云石之间的叶蜡石分成四个层面,采用X射线衍射对四个层面都进行了相结构测试与分析,并同时对四个层面的物相成分进行了半定量分析。结果表明:高温高压条件下叶蜡石的晶体结构发生了明显的变化,并逐渐相变成硬水铝石、柯石英、方英石;半定量分析结果表明,表层叶蜡石质量分数为83%,硬水铝石17%,靠近白云石的叶蜡石质量分数为59%,硬水铝石30%,柯石英8%,方石英3%,由叶蜡石粉压块表层到内部,叶蜡石结构逐渐被破坏,其它物相含量增加。这对于开展计算机模拟合成金刚石腔体温度场、压力场分布的工作提供了更加准确的物性参数获得方式。The pyrophyllite used as solid seal and pressure-transfer medium in diamond synthesis under high temperature and pressure was selected in this paper,and pyrophyllite between WC anvil and dolomite lining was divided into four layers,the phase transformation of pyrophyllite in four layers were studied by means of X-ray diffraction method.At the same time,the semi-quantitative analysis of mass fraction of each layer was calculated.XRD results showed that the pyrophyllite crystal structure was gradually decomposed into diaspore,coesite and cristobalite under high temperature and high pressure.The results of the semi-quantitative analysis of each layer showed that the surface of the pyrophyllite block contains 83%（mass fraction） of pyrophyllite,17% diaspore,while the internal of the pyrophyllite block which contacting the dolomite lining contains 59% of pyrophyllite,30% diaspore,8% coesite,3% cristobalite.From surface to internal,the pyrophyllite crystal structure was gradually destroyed and other phase contents increased.Thus it will provide a new method to obtain more accurate physical parameters in computer simulation of temperature field and pressure field in diamond synthetic chamber.

关 键 词：金刚石合成 叶蜡石 高温高压 相变 半定量分析 

分 类 号：TQ164[化学工程—高温制品工业]