This study examines sintering resistance of a thermal barrier coating (TBC), composed of a 7YSZ suspension plasma sprayed (SPS) top coat (TC), an air plasma sprayed (APS) NiCoCrAl bond coat (BC), and an INCONEL 625 substrate, under isothermal and cyclic conditions with a peak temperature of 1080 °C for 400, 800, and 1300 h/cycles. Microstructure, phase composition and microstrain were examined using SEM and XRD. Mechanical properties of fracture toughness, hardness and elastic modulus were obtained using nano-indentation. Samples under cyclic conditions presented faster sintering rate than under isothermal condition due to larger compressive strain and frequent heating and cooling cycles. Faster degradation of mechanical properties due to sintering leads to shorter lifetime of SPS coating under cyclic conditions. Moreover, vertical cracks within SPS coatings reduces compressive stress leading to a greater lifetime as compared to APS coatings exposed to similar conditions.

这项研究研究了由7YSZ悬浮等离子喷涂（SPS）顶涂层（TC），空气等离子喷涂（APS）NiCoCrAl粘结涂层（BC）和INCONEL 625基材组成的隔热涂层（TBC）的耐烧结性，在等温和循环条件下，峰值温度为1080°C，持续400、800和1300 h /循环。使用SEM和XRD检查了组织，相组成和微应变。使用纳米压痕获得断裂韧性，硬度和弹性模量的机械性能。由于更大的压缩应变以及频繁的加热和冷却循环，循环条件下的样品烧结速度比等温条件下更快。由于烧结而导致的机械性能的更快降低导致SPS涂层在循环条件下的寿命缩短。此外，