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热障涂层中黏结层的氧化性能与其成分及其组织结构有关,该文采用超音速火焰喷涂方法制备NiCoCrAlTaY涂层和CoNiCrAlY黏结层,通过组织结构研究和氧化性能试验,研究不同成分的黏结层对超音速火焰喷涂MCrAlY黏结层氧化性能的影响,以及热生长氧化物(thermallygrownoxides,TGO)的生长机理。研究结果表明超音速火焰喷涂过程中,MCrAlY粉末发生了氧化,黏结层中含有大量半球形粒子。两种涂层氧化25h前TGO以Al2O3为主,氧化100h后,在Al2O3膜表面出现了大量的Ni/Cr/Co氧化物。CoNiCrAlY涂层氧化动力学系数为0.272m/h1/2,略低于NiCoCrAlTaY涂层。Ni/Cr/Co氧化物的形成取决于Ni、Cr、Co等元素的扩散速度和Al2O3膜的生长速度。
Oxidation behavior of the adhesive layer in the thermal barrier coating is related to its composition and structure. In this paper, NiCoCrAlTaY coating and CoNiCrAlY adhesive layer were prepared by supersonic flame spraying. The structure and oxidation properties of NiCoCrAlTaY coating were studied. On the oxidation properties of supersaturated flame sprayed MCrAlY adhesive layer, and the growth mechanism of thermallygrownoxides (TGO). The results show that during supersonic flame spraying, MCrAlY powder is oxidized, and a large amount of hemispherical particles are contained in the adhesive layer. The TGO of the two coatings was mainly Al2O3 before 25 h of oxidation. After oxidation for 100 h, a large amount of Ni / Cr / Co oxide appeared on the surface of Al2O3 film. CoNiCrAlY coating oxidation kinetic coefficient of 0.272m / h1 / 2, slightly lower than the NiCoCrAlTaY coating. The formation of Ni / Cr / Co oxide depends on the diffusion rate of elements such as Ni, Cr and Co and the growth rate of Al2O3 film.