Calcium magnesium alumina-silicate (CMAS) corrosion on thermal barrier coatings (TBCs) is one of the reasons for the early delamination of TBCs. In this study, the effects of CMAS on the microstructure evolution of TBCs were investigated for yttria-stabilized zirconia (YSZ), lanthanum zirconate (LZ), and composite coating with a 50:50 volume ratio of LZ and YSZ (LZ-YSZ). The LZ showed the mitigated penetration of CMAS by the formation of the reaction products produced by the high reactivity between the LZ and the molten CMAS. The LZ-YSZ showed a denser microstructure on the surface, resulting in retarding the penetration of CMAS. Therefore, the LZ-YSZ composite TBC is expected to prolong the lifetime performance and protect against further corrosive degradation of TBCs in high-temperature environments. The infiltration behavior and reaction mechanism of molten CMAS were discussed based on the microstructures after the corrosion test.

中文翻译：

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CMAS在LZ-YSZ复合热障涂层中的渗透行为

热障涂层（TBC）上的钙镁铝硅酸盐（CMAS）腐蚀是TBC早期分层的原因之一。在本研究中，研究了 CMAS 对氧化钇稳定氧化锆 (YSZ)、锆酸镧 (LZ) 和 LZ 和 YSZ 体积比为 50:50 的复合涂层 (LZ-YSZ) 的 TBC 微观结构演变的影响. 通过形成由 LZ 和熔融 CMAS 之间的高反应性产生的反应产物，LZ 显示出 CMAS 的渗透减弱。LZ-YSZ 在表面显示出更致密的微观结构，从而阻碍了 CMAS 的渗透。因此，LZ-YSZ复合TBC有望延长寿命性能并防止TBC在高温环境中进一步腐蚀降解。