摘要
为了研究航空发动机热障涂层的失效机制,以及涂层界面间的三维形貌对涂层热应力的影响,使用ABAQUS有限元分析软件,计算了陶瓷层/粘结层结合界面间6种三维凹坑和凸起形貌单元形状以及尺寸对界面主应力σyy分布的影响规律.结果表明,形貌单元对界面应力有明显的影响,凹坑形貌界面上应力为压应力,凸起应力为拉应力,在形貌最低和最高处应力最大,尖角处应力相对集中.陶瓷层和粘结层的界面应力随着形貌单元尺寸的变化而发生变化,危险点处应力值随着纵向尺寸的增加而明显增大,曲率变化显著的地方存在着应力集中,曲率越大,应力越大.
In order to explain the failure mechanism of thermal barrier coatings in aeroengine,considering the difference of 3 dimension interface topography unit and size,the distribution of thermal stress σyy in aeroengine thermal barrier coatings was calculated using ABAQUS finite element analysis.The calculating result shows that the stress is affected by interface topography unit obviously.Compressive stress exists in concave tomography unit and tensile stress in convex topography unit.Stress concentrates on boundary of topography point and reaches maximal value at lowest and highest place of concave and convex topography respectively.Compressive and tensile stress changes with the size of topography unit distinctly.The value of stress in danger point becomes larger with the increase of the length.Stress concentrates when the change of curvature is obvious and increases with the increase of curvature.
出处
《焊接学报》
EI
CAS
CSCD
北大核心
2011年第10期21-24,114,共4页
Transactions of The China Welding Institution
基金
国家自然科学基金资助项目(60879018)
关键词
热障涂层
热应力
界面形貌
有限元分析
thermal barrier coatings
residual stress
interface topography
finite element analysis
