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烧绿石结构的稀土锆酸盐材料是新型热障涂层的潜在候选材料之一，能进一步提升涡轮发动机使用寿命和可靠性。通过大气等离子体喷涂技术制备了Sm2Zr2O7热障涂层，并对其显微结构和相组成进行表征。Sm2Zr2O7涂层表现出阴离子无序和阳离子有序的萤石相结构特征。经过高温热处理后，涂层结构的向有序方向转变。当热处理温度超过1200℃时，涂层转变为有序的烧绿石结构。热处理温度升高造成涂层中微裂纹的愈合，导致Sm2Zr2O7，涂层典型的片层结构特征消失。“,”Rare-earth zirconates with a pyrochlore structure have attracted great attention for potential application in thermal barrier coatings to further improve the performance and durability of gas turbines. In present work, the SmzZr2O7 coating was deposited by air plasma spraying technology, and its microstructure and phase composition were examined. The as-sprayed SmzZr2O7 coating exhibited anion-disordered while cation-ordered fluorite-type structure. Degree of ordering was considerable enhanced after high temperature aging, and transformed to ordered pyrochlore- type structure after thermal aging at temperatures above 1200℃. The typical lamellar structure for the as-sprayed Sm2Zr2O7 coating gradually decreased with increasing thermal aging temperature, which was caused by microcrack healing at high temperatures.