摘要
针对带等离子喷涂热障陶瓷涂层的圆筒金属基体结构在典型热循环载荷作用条件下的力学响应进行了数值计算,基于陶瓷层中的应力结果对陶瓷层剥落失效机理展开了分析.计算时对陶瓷层材料分别按理想线弹性本构和黏塑性本构模型开展了模拟.分析发现,陶瓷层的界面(横向)开裂存在两种模式:在降温过程中,陶瓷层容易出现界面波峰处的Ⅰ型开裂与腰部位置处的Ⅱ型开裂;在升温过程中,陶瓷层容易发生垂直开裂使结构中出现陶瓷层/基体的界面端,界面端部严重的应力集中效应使陶瓷层容易在该处横向开裂形成界面处的边裂纹.
A numerical simulation of a cylindrical system with plasma sprayed thermal barrier coatings under typical thermal loading was conducted,and the failure mechanisms were analyzed based on the stresses in ceramic coat. It is found that,there are two types of interfacial （transverse） cracking patterns of the ceramic coat：in the cooling process,mode Ⅰ is vulnerable to crack at the peak position of the cosine curve,and mode Ⅱ at the middle position; in the heating process,interface edges are introduced into the ceramic coat/substrate system as a result of the vertical cracks emergence,and the ceramic coat will transversely crack at these positions because of the stress concentration effect.
出处
《航空动力学报》
EI
CAS
CSCD
北大核心
2010年第5期1085-1091,共7页
Journal of Aerospace Power
关键词
热障涂层
黏塑性
应力分析
界面
有限元法
thermal barrier coatings
viscoplasticity
stress analysis
interfaces
finite element method
