纳米SrCe_(0.95)Y(0.05)O_(3-x)陶瓷粉的制备与烧结

Preparation and sintering behavior of nanosized pure SrCe_(0.95)Y_(0.05)O_(3-x) powders

采用基于Pechini法的低温燃烧工艺制备了SrCe0.95Y0.05O3-x(SCY)前驱物.前驱物在900℃经0.5 h的煅烧处理即可得到纯的粒度在7～25 nm范围内的SrCe0.95Y0.05O3-x固体电解质纳米粉.将煅烧的粉体在18 MPa压力下压成片状的素坯,在900～1 500℃的温度范围内于空气中烧结索坯10 h.用X射线衍射(XRD)表征煅烧粉体的晶体结构,用扫描电镜(SEM)和透射电镜(TEM)表征了煅烧粉体和烧结体的形貌和粒度,采用阿基米德法测量了烧结体的密度.结果表明:温度达到1 000℃时,烧结体的径向收缩率和密度随着温度的升高而显著增加;温度达1 300℃时烧结体的径向收缩率和密度趋于恒定,得到相对密度高于96%、平均粒径约为3.68 μm的SrCe095Y0.05O3-x固体电解质陶瓷体.

Precursors for SrCe_(0.95)Y_(0.05)O_(3-x) (SCY) were synthesized by sol-combustion process based on the Pechini method. Pure SrCe_(0.95)Y_(0.05)O_(3-x) nanosized powders with the size range of 725nm were obtained after calcining the precursors at 900℃ for 0.5h. The calcined powders were pressed into pellets at 18MPa. These pellets were sintered at the temperature range of 9001500℃ for 10h in air. The crystal structure of the calcined powders was analyzed using XRD. The morphology and crystallite sizes of the calcined powders and the sintered pellets were observed using SEM and TEM. The densities of the sintered pellets were measured using Archimedes method with water. The results indicate that, at 1000℃ and above, the radial shrinkage and the density of the sintered pellets obviously increase; at a temperature as high as 1300℃, nearly fully dense SrCe_(0.95)Y_(0.05)O_(3-x) ceramic (relative density larger than 96%) with a mean grain size of 3.68μm can be obtained.