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氮化硅陶瓷有极大的应用潜力，但由于其强共价键，很难烧结致密化。采用了一种新的ＭｇＯ－ＣｅＯ２复合烧结助剂，利用Ｘ射线衍射、透射电镜等手段研究了ＭｇＯ－ＣｅＯ２复合烧结助剂对氮化硅陶瓷致密化和相变过程的影响，结果发现对Ｓｉ３Ｎ４－ＭｇＯ－ＣｅＯ２陶瓷，在１４５０℃就会有大量液相出现，１５００～１５５０℃为快速致密化阶段，而α－Ｓｉ３Ｎ４→β－Ｓｉ３Ｎ４相变主要发生在１５５０～１６００℃，相变过程滞后于致密化过程。常压烧结Ｓｉ３Ｎ４－ＭｇＯ－ＣｅＯ２陶瓷，强度达９４８ＭＰａ，因此，ＭｇＯ－ＣｅＯ２是一种非常有效的氮化硅的烧结助剂。
Silicon nitride ceramics have great potential applications, but because of its strong covalent bond, it is difficult to densification sintering. A new MgO-CeO2 composite sintering aids was used to study the effect of MgO-CeO2 sintering aids on the densification and phase transition of Si3N4 ceramics by means of X-ray diffraction and transmission electron microscopy. It was found that Si3N4 -MgO-CeO2 ceramics, there will be a large number of liquid phase at 1450 ℃, 1500 ~ 1550 ℃ for the rapid densification stage, and α-Si3N4 → β-Si3N4 phase transition occurs mainly in 1550 ~ 1600 ℃, the phase transition lags behind Densification process. Atmospheric pressure sintering Si3N4-MgO-CeO2 ceramics, the strength of 948MPa, therefore, MgO-CeO2 is a very effective sintering aid of silicon nitride.