Si3N4－MgO－CeO2陶瓷烧结过程中MgO的自动析晶
来源期刊：中南大学学报(自然科学版)1996年第5期
论文作者：杨海涛 徐润泽 黄培云
文章页码：70 - 74
关键词：氮化硅; 玻璃相; 析晶
Key words：Si3N4; glassy phase; crystallization
摘 要：作者首次发现了Si3N4－MgO－CeO2系陶瓷在烧结过程中玻璃相自动析晶这一独特现象.对于Si3N4－MgO－CeO2系陶瓷在1450℃,MgO－CeO2就会与Si3N4颗粒表面的SiO2反应形成硅酸盐液相,冷却后则成为玻璃相保留在烧结体中;当烧结温度高于1550℃时,作者发现,CeO2仍留在玻璃相中,但MgO会自动析晶出来,其结果是大大减少了烧结体中严重影响其高温性能的玻璃相的含量,对于提高烧结氮化硅陶瓷的高温性能有重要作用.
Abstract: The automatic crystallization of the glassy phase in the sintering of Si3N4 with MgO-CeO2 was first discovered. The MgO-CeO2 would react with the SiO2 to form silicate liquid phase at 1450 ℃; above 1550 ℃, MgO would crystallize, and the glassy phase in the sintered bodies contained hardly any MgO. The amount of the glassy phase which was harmful to the high temperature performance was then greatly decreased. This results in the good performance both at room temperature and high temperature for the sintered Si3N4 ceramics. The present study is of great value in both theoretical study and application.
