高能态微米尺度粉体的低温烧结制备细晶陶瓷与致密化过程研究

为了获得细晶陶瓷材料，通常利用低温烧结致密化纳米尺度的粉体来实现。但是由于纳米粉体具有高表面能，导致粉体易团聚并且烧结过程中晶粒生长难以控制，所以采用纳米粉体制备细晶陶瓷仍然存在着技术上难题。. 针对上述问题，本项目提出了采用具有特殊微结构的微米尺度粉体（如介孔Y2O3、Al2O3、ZrO2，YAG等）为原料，建立一种低温烧结制备细晶陶瓷材料的新方法。首先合成具有不同微结构（不同孔径尺寸等）粉体，然后研究烧结致密化过程中其微结构坍塌（例如有序孔道破坏）使得微米尺度原料颗粒演变成小颗粒过程，阐明烧结过程中由于颗粒尺寸演变原位增加烧结驱动力的烧结机理，最后进行材料结构与性能的研究。 通过本项目的研究，发展一种采用微米尺度粉体低温烧结制备细晶陶瓷的可行途径。

Nano-sized powders are densified for fabricating fine-grained ceramics at low temperature. However, nano-sized powders are easily agglomerated, and that grain growth during sintering process is inevitable. Thus, it is still a challenge for using nano-size powders to prepare fine grain ceramics.. In this project, a novel method is proposed for fabricating fine-grained ceramics at low temperature. Firstly, mesoporous powders such as Y2O3, Al2O3, ZrO2, YAG powders with different pore size are synthesized; secondly, these mesoporous powders break into smaller particles and order-structure developing process of these powders during sintering process are investigated in detail, and the mechanism of sintering driving force increasing will be given; finally, the microstructure and properties of as-prepared bulk materials are investigate. The purposes of the project is developed a new route to prepare fine-grained ceramics used micro-sized powders as starting materials at low temperature.