多层结构热障涂层抗热震性能的研究

Thermal Shock Resistance of Multilayer Thermal Barrier Coatings(TBCs)

摘要:

本文采用电子束物理气相沉积技术(EB-PVD)在镍基单晶合金N5基体上制备了双层热障涂层(粘结层+陶瓷层)和三层热障涂层(粘结层+混合层+陶瓷层),并对两组涂层体系的热循环性能进行1100℃保温5min 水冷的热震实验,对其微观组织结构采用扫描电镜、能谱仪以及X射线衍射进行了分析。研究发现,在粘结层和陶瓷层之间添加的混合层(NiCrAlY+YSZ)能够延缓TGO层的生长,并具有缓解内应力的作用,两者的共同作用使得三层结构的热障涂层表现出更为优异的热匹配性。

Abstract:

In this article,two layer and three layer TBCs were deposited by electron beam physical vapor deposition(EB-PVD) on the Ni-based superalloy (N5) . Thermal shocktest of the coatings was carried out by heating the coating from room temperature to 1100℃ for 5 min, followed by water quenching. After the microstructural characterization was analysed by SEM, EDS and XRD, the result showed that the mixture layer, composite by NiCrAlY and YSZ, can retard the growth of TGO layer and reduce the inter-stress between bond coating and top coating. Both of them improved the thermal math performance of three layers TBCs.