叶蜡石高温相转变的实验研究  

Experimental study of high temperature phase transformation for pyrophyllite

作　　者：魏存弟[1,2] 马鸿文[1] 杨永强[1] 杨殿范[3] 三国彰 

机构地区：[1]中国地质大学材料科学与工程学院 [2]吉林大学汽车材料教育部重点实验室,吉林长春130026 [3]吉林大学汽车材料教育部重点实验室 [4]日本山口县产业技术中心

出　　处：《地学前缘》2005年第1期214-219,共6页Earth Science Frontiers

基　　金：国家留学基金委出国留学基金项目(2003)

摘　　要：通过差热分析、X射线衍射分析、红外光谱分析和魔角旋转核磁共振等测试手段,研究了日本广岛胜光山叶蜡石在20～1300℃下煅烧的相转变过程.结果表明,叶蜡石的高温相转变经历了4个阶段:叶蜡石阶段(室温～662℃),偏叶蜡石阶段(662～1100℃),不定形SiO2与莫来石形成阶段(1100～1200℃)和莫来石与方石英共存阶段(1300℃～).叶蜡石在662℃时失去结构水转变为偏叶蜡石.偏叶蜡石从1100℃开始转变为莫来石,同时伴随有不定形SiO2生成.1300℃时,不定形SiO2进一步结晶形成方石英.By means of the technique of DAT, XRD, IR and MAS NMR, the phase transformation for calcined pyrophyllite sample taken from Hiroshima in Japan, was studied under 20 to 1 300 ℃ temperature. Some important conclusions were drawn as follows: phase transformation for pyrophyllite was undergone 4 stages, including pyrophyllite stage (indoor temperature to 662 ℃), pyrophyllite anhydride stage (662 to 1 100 ℃),amorphous SiO_2 and mullite crystallite forming stage (1 100 to 1 200 ℃), and coexistence stage of mullite and cristobalite(over 1 300 ℃). At the point of 662 ℃, the pyrophyllite was dehydrated , and changed into pyrophyllite anhydride. The pyrophyllite anhydride was changed into mullite at the point of 1 100 ℃, at the same time, amorphous SiO_2 was formed. Furthermore, when temperature approaching 1 300 ℃, amorphous SiO_2 was crystallized into cristobalite.

关 键 词：叶蜡石 相转变 魔角旋转核磁共振 偏叶蜡石 莫来石 方石英 

分 类 号：P578[天文地球—矿物学]