Y_2O_3粉体分散性对固相反应法制备YAG透明陶瓷的影响

Influence of Dispersivity of Y_2O_3 Powders on Fabrication of the Transparent YAG Ceramics Made by Solid-state Reaction Method

以分散性不同的Y2O3纳米粉为原料,利用固相反应法合成YAG超细粉。在不同的制备条件下,针对Y2O3纳米粉的分散性对固相反应进程的物相变化、显微组织及YAG陶瓷体透光性的影响进行了观察和研究。结果表明,Y2O3纳米粉的分散性决定其反应活性,是影响固相反应进程的主要因素。将高活性的Y2O3纳米粉与Al2O3粉均匀混合,可促进固相反应的完成并有效降低烧结温度,使真空烧结后的YAG陶瓷组织更加均匀,有利于烧结后期孤立气孔的排除。

The ultrafine YAG powders were synthesized by solid-state reaction method using Y2O3 nanopow- ders with different dispersivity. The phase transformation during the reaction, transparency and microstructure of YAG ceramics were investigated. The results show that the dispersivity of Y20a nanopowder decides its reactivity, which is the major influence factor of solid-state reaction. When highly active Y2O3 nanopowders used as the starting materials are uniformly mixed with Al2O3 powders, the solid-state reaction is obviously improved and the sintering temperature is reduced effectively. Furthermore, the highly active Y2O3 nanopowders are also helpful to remove the isolated pores on the grain boundary during the final sintering stage and the microstructure of vacuum-sintered YAG ceramics are more homogeneously.