界面形貌对热障涂层界面残余应力影响的数值模拟

利用有限元方法 ,对热障涂层热循环降温过程中产生的残余应力进行了数值模拟 ,研究了有尖点和无尖点正弦波形微坑以及矩形微坑对界面残余应力的影响。结果表明 ,微坑形状不同 ,界面上残余应力的大小、性质与分布也不同 ;微坑的形状变化和尖点的出现 ,将会使该处的应力发生突变 ,不利于增强界面结合强度。因此 ,从对热障涂层界面残余应力的影响角度看 ,无尖点的正弦波形微坑既优于有尖点微坑也优于矩形微坑

Numerical Simulation of Interfacial Residual Stresses in Thermal Barrier Coatings Induced by Interface Topography

The residual stresses in thermal barrier coatings during cooling of heat cycles were numerically simulated by finite element method in this paper,with an attempt to understand the influences of interface topography,rectangle micro pit,sinusoid with tip and without tip,on interfacial residual stresses distribution.It shows that,interfacial residual stress distribution is varied with the shape of micro pit and the variation of micro pit and appearance of tip will cause the sudden change of stresses which is bad to interface bonding.On the opinion of the influences on the interfacial residual stressed in thermal barrier coatings,the sinusoid micro pit without tip is better than both micro tip sinusoid with tip and rectangle.