论文部分内容阅读
采用等离子喷涂技术在高温合金上制备了热障涂层(粘接层为NiCoCrAlY,陶瓷层为ZrO2-8%Y2O3),利用扫描电镜(SEM)、拉曼光谱(RFS)等试验手段研究了热障涂层热震失效的过程及残余应力大小和分布状态。结果表明:150次热循环后,陶瓷层和热生长氧化物(TGO)生成裂纹,其中陶瓷层的裂纹已扩展至TGO;350次热循环后,出现贯通陶瓷层与金属过渡层的纵向裂纹,涂层局部出现剥离,剥离位置位于TGO与陶瓷层界面;拉曼光谱(RFS)分析结果显示TGO内应力水平分布不均,局部厚大区和凸凹处残余应力较大,是裂纹萌生、扩展的主要部位。
The thermal barrier coating (NiCoCrAlY as bonding layer and ZrO2-8% Y2O3 as ceramic layer) was prepared by plasma spray technique on hot superalloy. The effects of heat Thermal shock failure process of barrier coatings and the size and distribution of residual stress. The results show that after 150 thermal cycles, the ceramic layer and the TGO generate cracks, in which the cracks in the ceramic layer have been extended to TGO. After 350 thermal cycles, longitudinal cracks occur in the ceramic layer and the metal transition layer, The results of Raman spectroscopy (RFS) analysis show that the stress levels in TGO are unevenly distributed, and the residual stresses in local thick regions and bump are larger, which are the initiation and propagation of cracks The main part.