TEM observation on nucleation of Ca α-Sialon  

作　　者：Yawen Li Peiling Wang Weiwu Chen Jingwei Feng Dongsheng Yan Yibing Cheng 

出　　处：《Chinese Science Bulletin》2001年第3期216-219,共4页

基　　金：This work was supported by the National Natural Science Foundation of China (Grant Nos. 59810760327 and 59872049).

摘　　要：Ca α-Sialon compacts pressurelessly-sintered tothe intermediate temperature (1 450℃) were investigated with TEM for an overall composition Ca1.8Si6.6Al5.4O1.8N14.2. It was found that in most cases, the newly-formed α-Sialon grains had no epitaxial orientation relationship with the Si3-N4 particles; only occasionally heteroepitaxial nucleation of α-Sialon on α-Si3N4 was detected. Further EDAX analysis revealed a much higher Ca concentration in the non-epi-taxially nucleated α-Sialon than in the heteroepitaxially nucleated α-Sialon. Thus a possible correlation between the concentration of metal cations in the (a-Sialon structure and the nucleation mechanism has been proposed, i.e. α-Sialon compositions with higher Ca concentration show a stronger trend of non-epitaxial nucleation.Ca α-Sialon compacts pressurelessly-sintered to the intermediate temperature (1 450°C) were investigated with TEM for an overall composition Ca1.8Si6.6Al5.4O1.8N14.2. It was found that in most cases, the newly-formed α-Sialon grains had no epitaxial orientation relationship with the Si3N4 particles; only occasionally heteroepitaxial nucleation of α-Sialon on α-Si3N4 was detected. Further EDAX analysis revealed a much higher Ca concentration in the non-epitaxially nucleated α-Sialon than in the heteroepitaxially nucleated α-Sialon. Thus a possible correlation between the concentration of metal cations in the α-Sialon structure and the nucleation mechanism has been proposed, i.e. α-Sialon compositions with higher Ca concentration show a stronger trend of non-epitaxial nucleation.

关 键 词：CA Α-SIALON TEM NUCLEATION mechanism. 

分 类 号：TQ175[化学工程—硅酸盐工业]