采用大气等离子喷涂制备了纳米结构氧化钇稳定的氧化锆热障涂层。运用SEM ,TEM和XRD等方法研究了涂层和原料粉末的微观结构和相组成。结果表明 ,喷涂过程中平均晶粒大小由4 0nm变为 6 7nm ,涂层主要由亚稳四方相组成。涂层热处理结果显示 ,90 0℃以下晶粒长大速度缓慢 ,然而 1 0 0 0℃以上晶粒长大速度迅速增加 ,而且出现较多的单斜相 Nanostructured yttria-stabilized zirconia thermal barrier coatings were prepared by atmospheric plasma spraying. The microstructure and phase composition of coating and raw material powder were studied by SEM, TEM and XRD. The results show that the average grain size changes from 40 nm to 67 nm during the spraying process, and the coating mainly consists of metastable tetragonal phase. The results of the coating heat treatment show that the grain growth rate is slow at 90 0 ℃, however, the grain growth rate is rapidly increased at the temperature above 100 ℃, and more monoclinic phase