天然树化玉的显微结构及力学性能

MICROSTRUCTURE AND MECHANICAL PROPERTY OF NATURAL TREE JADE

采用扫描电镜、X射线荧光仪、X射线衍射仪和电子万能材料试验机对树化玉的显微结构、成分及力学性能进行研究。结果表明:树化玉主要由硅和氧两种元素组成,含有的少量着色离子使其呈现不同颜色。树化玉在形成过程中要通过矿物质之间的"交代作用",同时还要依靠石英晶体的结晶析出。树化玉主晶相属于三方晶系的α-石英,但同时存在属于四方晶系的α-方石英。受形成环境影响,树化玉的抗弯强度、断裂韧性及硬度低于氧化锆和氧化铝陶瓷的。

The microstructure,composition and mechanical properties of tree jade were investigated by scanning electron microscope,X-ray fluorescence spectrometer,X-ray diffractometer and electronic universal testing machines.The results show that the tree jade consists of silicon and oxygen,and a small amount of coloring ion makes them exhibit different colors.The formation of the tree jade depends not only on the metasomatism of minerals but also on the crystallization of quartz crystal.The main crystal phase of the tree jade belongs to the trigonal system of α-quartz phase.There also exists α-cristobalite phase which belongs to the tetragonal system.The bending strength,fracture toughness and hardness of the tree jade are lower than zirconium oxide and alumina ceramics due to the formation environment of the tree jade.