Calcium magnesium aluminum silicate (CMAS) is one of the leading concerns for the gas turbine industry. The effects of CMAS viscosity and the coating microstructure on CMAS infiltration depth were explored by conducting a time dependent interaction study. Three CMAS compositions were used from literature, and their viscosities predicted through FactSage viscosity module were drastically different. The interaction was carried out on three different TBCs synthesized using the solution precursor plasma spray process (SPPS): two of the TBCs were made of yttrium aluminum garnet (YAG) having different microstructures that promote different modes of CMAS infiltration, and one TBC was made of gadolinium zirconate (GZO). All samples had stress relieving vertical cracks and different intensities of horizontally banded porosity, (inter pass boundaries IPBs). A concentration of 100 mg/cm² of CMAS was applied on the TBCs which were then subjected to a 5-minute interaction at 1300 °C. Samples were analyzed using scanning electron microscopy (SEM), electron dispersive X-ray spectroscopy (EDXS), and transmission electron microscopy (TEM). Low viscosity CMAS readily penetrated the TBCs while more viscous CMAS showed less penetration. The depth of CMAS infiltration depended on the coating microstructure. In the YAG with IPBs, the CMAS spread horizontally in the IPBs before infiltrating deeper, resulting in reduced infiltration depth compared to other samples in spite of having wider vertical cracks. TEM and EDXS analysis were performed to investigate the phases present in the CMAS-TBC interaction region in YAG. Two regions were chosen, the top TBC surface in direct contact with the sea of CMAS, and the region at the CMAS penetration ended within the coating. The results showed that no secondary phases like apatite were observed in YAG, thus it can be concluded that the arrest of CMAS happened solely because of CMAS viscosity and the short infiltration time.

钙镁铝硅酸盐(CMAS) 是燃气轮机行业的主要关注点之一。通过进行时间相关的相互作用研究，探讨了CMAS 粘度和涂层微观结构对 CMAS渗透深度的影响。使用了文献中的三种 CMAS 组合物，它们通过 FactSage 粘度模块预测的粘度差异很大。相互作用是在使用溶液前体等离子喷涂工艺 (SPPS) 合成的三种不同 TBC 上进行的：其中两种 TBC 由具有不同微观结构的钇铝石榴石(YAG)制成，可促进不同模式的 CMAS 渗透，另一种 TBC 由钆锆酸盐 (GZO)。所有样品都具有消除应力的垂直裂纹和不同强度的水平带状孔隙度（通道间边界 IPB）。浓度为 100 mg/cm ²将 CMAS 应用于 TBC，然后在 1300 °C 下进行 5 分钟的相互作用。使用扫描电子显微镜 (SEM)、电子色散 X 射线光谱 (EDXS) 和透射电子显微镜 (TEM) 分析样品。低粘度 CMAS 很容易穿透 TBC，而粘度更高的 CMAS 则显示出更少的穿透力。CMAS 渗透的深度取决于涂层的微观结构。在具有 IPB 的 YAG 中，CMAS 在 IPB 中水平扩展，然后渗透更深，尽管垂直裂缝较宽，但与其他样品相比，渗透深度降低。进行 TEM 和 EDXS 分析以研究 YAG 中 CMAS-TBC 相互作用区域中存在的相。选择了两个区域，顶部 TBC 表面与 CMAS 海直接接触，CMAS 穿透的区域在涂层内结束。结果表明，没有第二相像在 YAG 中观察到磷灰石，因此可以得出结论，CMAS 的停滞完全是因为 CMAS 的粘度和渗透时间短。