CAJ | 학술논문

采用两种加热方式对氟云母晶体和普通钠钙玻璃混合粉末进行烧结,用扫描电镜观察烧结过程中玻璃陶瓷的组织演变,结合样品收缩率和密度的变化,研究了玻璃陶瓷的致密化行为.研究结果表明,致密化是通过玻璃的粘性流动实现的,氟云母加入对玻璃粘性流动有阻碍,降低了烧结驱动力.加热至850 ℃,氟云母与玻璃发生反应析晶形成氟闪石,对致密化影响很大.反应析晶发生前,玻璃陶瓷的密度随温度升高和等温时间延长而提高;反应析晶发生后,逐渐形成密集的相互交织的氟闪石晶体骨架对玻璃粘性流动产生严重阻碍,玻璃陶瓷的密度随温度升高略有下降.
채용량충가열방식대불운모정체화보통납개파리혼합분말진행소결,용소묘전경관찰소결과정중파리도자적조직연변,결합양품수축솔화밀도적변화,연구료파리도자적치밀화행위.연구결과표명,치밀화시통과파리적점성류동실현적,불운모가입대파리점성류동유조애,강저료소결구동력.가열지850 ℃,불운모여파리발생반응석정형성불섬석,대치밀화영향흔대.반응석정발생전,파리도자적밀도수온도승고화등온시간연장이제고;반응석정발생후,축점형성밀집적상호교직적불섬석정체골가대파리점성류동산생엄중조애,파리도자적밀도수온도승고략유하강.
The sintering of powder compacts of fluormica and soda-lime glass was performed by two types of heating schedules. The densification behaviors of the glass-ceramics were studied by means of the observation of their microstructural evolution using scanning electron microscopy and the measurement of the changes in the shrinkage and density of the compacts during sintering. The results show that the densification of glass-ceramics is achieved by the viscous flow of glassy　phase, the fluormica addition inhibites the viscous flow of glassy phase and reduces the driving force of sintering. Heating up to 850 ℃, fluoramphibole is formed by a reactive crystallization between fluormica and glass,which had a significant influence on the densification. The density of glass-ceramics increases with sintering temperature and isothermal time before the reactive crystallization, but decreases slightly after it because a dense interlocked rod-like fluoramphibole crystal skeleton formes gradually and seriously retards the viscous flow of glassy phase.