Calcium-magnesium-alumino-silicate (CMAS) induced degradation of the La₂(Zr_0.7Ce_0.3)₂O₇/YSZ double-ceramic-layer thermal barrier coatings (TBCs) prepared by electron beam-physical vapor deposition (EB-PVD) was investigated in this study. CMAS reacted with La₂(Zr_0.7Ce_0.3)₂O₇ to form a dense crystalline layer composed of apatite and fluorite phases, while the penetration was not arrested in the double-ceramic-layer coating due to the formation of vertical cracks during heat-treatment. In fact, the vertical cracks in the LZ7C3 layer inevitably provided efficient infiltration paths for molten CMAS to attack the bottom YSZ layer. Since the formation of Ca₂(La_1-xCe_x)₈(SiO₄)₆O₂₆ apatite phase during CMAS reactions led to CaO enrichment in the melt, the YSZ buffer layer of the double-ceramic-layer coating even suffered a severer CMAS attack than the single YSZ coating.

钙镁铝硅酸盐（CMAS）诱导的La ₂（Zr _0.7 Ce _0.3）₂ O ₇ / YSZ双陶瓷层热障涂层的降解，通过电子束物理气相沉积（EB-PVD）制备）在此研究中进行了调查。CMAS与La ₂（Zr _0.7 Ce _0.3）₂ O _7反应形成由磷灰石和萤石相组成的致密结晶层，而由于在热处理过程中形成垂直裂纹，在双陶瓷层涂层中的渗透没有被阻止。实际上，LZ7C3层中的垂直裂缝不可避免地为熔融CMAS提供了有效的渗透路径，以侵蚀底部的YSZ层。由于在CMAS反应过程中形成Ca ₂（La _1-x Ce _x）₈（SiO ₄）₆ O ₂₆磷灰石相导致CaO在熔体中富集，因此双陶瓷层涂层的YSZ缓冲层甚至遭受比单一的YSZ涂层更严重的CMAS攻击。