Al_2O_3对9YSZ固体电解质烧结及晶粒长大行为的影响

Effects of Alumina as Dopant on Sintering and Grain Growth Behavior of 9 mol% Yttria-Stabilized Zirconia

采用化学共沉淀法制备了掺杂Al2O3的9%(摩尔分数)钇稳定氧化锆固体电解质(9YSZ).利用XRD计算了Al2O3掺杂9YSZ的晶格参数,研究了Al2O3在9YSZ中的固溶度,考察了Al2O3掺杂量对9YSZ烧结性能和晶粒长大行为的影响.研究结果表明,当Al2O3掺杂量增加到0.48%(质量分数)时,9YSZ晶格参数从0.514 08 nm降低到0.513 51 nm,继续掺杂Al2O3,则晶格参数不变,说明Al2O3在9YSZ中的固溶度为0.48%(质量分数).掺杂Al2O3能提高9YSZ的烧结性能,促使晶粒长大,使9YSZ更加致密.

Al2O3-doped 9 mol% yttria-stabilized zirconia（9YSZ） was synthesized by the chemical co-precipitation of hydroxides.The solid solubility of Al2O3 as dopant in 9YSZ was characterized by XRD,with the lattice parameters calculated.Then,the effects of Al2O3 on sintering and grain growth behavior of 9YSZ was investigated.The result showed that the lattice parameter of YSZ decreases from 0.514 08 nm to 0.513 51 nm when the doped Al2O3 is increased up to 0.48wt%,but the lattice parameter remains unchanged if the Al2O3 is doped further.It means that the limit of solid solubility of Al2O3 in 9YSZ is about 0.48wt% and that the Al2O3 as dopant can accelerate the sintering process so as to hurry up the grain growth and make 9YSZ denser.