ZrO_2、La_2Zr_2O_7梯度涂层的显微结构研究

Study on Microstructure of ZrO_2 and La_2Zr_2O_7 Graded Coatings

采用微弧等离子喷涂设备在1Cr18Ni9上制备了ZrO2、La2Zr2O7梯度热障涂层;利用扫描电镜研究了涂层的显微结构。结果表明:梯度涂层呈典型的层状结构,涂层较为致密,空隙均匀,同时分布有各向的微裂纹。涂层中分布有未完全融化的La2Zr2O7颗粒,保留了其喷涂前的纳米结构。ZrO2、La2Zr2O7两种材料在涂层中的熔合较好,结合较为紧密,这对提高涂层的结合强度是非常有益的。

ZrO2 and La2Zr2O7 graded coatings was prepared on 1Cr18Ni9 substrate metal by micro-arc plasma spraying process. Its microstructure characteristics were studied by SEM. The results show that the graded thermal barrier coatings have typical lamellar structure. The coatings are compact. Some pores and micro-cracks are dispersed in the coatings. There are some unmelten La2Zr2O7 particles which have nano-structure. ZrO2 and La2Zr2O7 melt down and bond each other in the coatings, which is in great favor of enhancing the adherent strength of the coatings.