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采用炸药爆炸驱动飞片加载技术，实现了两种压力（１５．７和２５．６ＧＰａ）的冲击波加载，对氮化硅粉末进行冲击波活化研究．通过运用ＴＥＭ，ＳＥＭ，ＸＲＤ等手段分析了粉末和烧结陶瓷的特性，测试了烧结试件的力学性能．对经过冲击波活化和未经活化的粉末特性比较后得知：在冲击波作用过的粉末中没有发现明显的相变和聚结现象，而粉末颗粒结构中则出现了大量的位错及位错群．对活化粉和未活化粉掺混相同的烧结助剂（５％ＭｇＯ＋５％ＣｅＯ２）后，在相同的热压烧结工艺条件下进行烧结，结果表明：冲击波活化明显促进烧结的致密化过程，而烧结温度则决定Ｓｉ３Ｎ４的相变过程．因此烧结件的强度将与两者的综合效应相关．
In this paper, explosive charge-driven flyer loading technology was used to carry out shock wave loading of two kinds of pressure (15.7 and 25.6GPa) and shock wave activation of silicon nitride powder. The properties of powders and sintered ceramics were analyzed by means of TEM, SEM and XRD, and the mechanical properties of sintered samples were tested. Comparing the properties of the activated and unactivated powders after shock wave, we can see that there is no obvious phase transition and coalescence in the powder with shock wave, but a large number of dislocations and dislocation groups appear in the powder particle structure . The same sintering aids (5% MgO + 5% CeO2) were blended with activated and non-activated powders and sintered under the same hot-pressing conditions. The results show that the activation of shock wave obviously promotes the densification of sintering and the sintering The temperature determines the phase transition of Si3N4. The strength of the sintered part will therefore be related to the combined effects of both.