Glassy deposits mainly comprising of calcium–magnesium–alumina–silicate (CMAS) accelerate the spallation of thermal barrier coatings (TBCs). In this work, an Al₂O₃ layer was produced on yttria-stabilized zirconia (YSZ) coating by plasma spray–physical vapor deposition (PS–PVD). The effects of processing parameters during PS–PVD process on the microstructures of the deposited Al₂O₃ coatings were investigated. A homogeneous Al₂O₃ coating with porosity less than 1% was deposited at the spray distance of 1400 mm, which is much denser than the coating produced by atmospheric plasma spray (APS) and other PS–PVD coatings sprayed at 1000 and 1900 mm. The CMAS corrosion test at 1250 °C showed that the APS Al₂O₃ layer was dissolved in CMAS after 24 h thermal exposure, whereas a dense reaction layer mainly composed of anorthite formed on the top region of the PS–PVD Al₂O₃ layer effectively protected the underlying Al₂O₃ layer from CMAS infiltration. Thermal cycling behavior of the PS–PVD Al₂O₃/YSZ TBC and the APS Al₂O₃/YSZ TBC at 1050 °C was compared. Bulk spallation of the APS TBC occurred within 300 h thermal cycling, while little spallation was observed on the PS–PVD TBC even after 500 h thermal cycling, indicating superior durability of the PS–PVD coating.

主要由钙，镁，铝，硅酸盐（CMAS）组成的玻璃状沉积物会加速热障涂层（TBC）的剥落。在这项工作中，通过等离子喷涂–物理气相沉积（PS–PVD）在氧化钇稳定的氧化锆（YSZ）涂层上产生了Al ₂ O ₃层。研究了PS-PVD工艺中工艺参数对沉积的Al ₂ O ₃涂层微观结构的影响。均匀的Al ₂ O ₃孔隙率小于1％的涂层在1400 mm的喷涂距离处沉积，比常压等离子体喷涂（APS）和其他在1000和1900 mm喷涂的PS-PVD涂层产生的涂层致密得多。在1250°C下进行的CMAS腐蚀测试表明，在热暴露24 h后，APS Al ₂ O ₃层溶解在CMAS中，而在PS–PVD Al ₂ O ₃顶部区域上形成了一个主要由钙长石组成的致密反应层层有效地保护了下面的Al ₂ O ₃层免受CMAS渗透。PS–PVD Al ₂ O ₃ / YSZ TBC和APS Al ₂ O _3的热循环行为比较了1050°C下的/ YSZ TBC。APS TBC的散裂发生在300 h的热循环内，而PS–PVD TBC甚至在500 h的热循环后也观察不到散裂，这表明PS–PVD涂层具有出色的耐久性。