In order to get the laws of the influences of the thermal grown oxide (TGO) thickening on the thermal barrier coatings residual stress,based on the previous works on TBCs temperature,the residual stress of TBCs is studied considering the material properties dependence on temperature,TGO layer thickening and the accumulated creep strain after 50 thermal cycles.The results indicate that the max thickness of TGO appears in the tail of the vane for higher temperature;As the thickness of TGO exceeds 2 μm,the increased max principal stress grows up with the TGO thickness,which may result in failure of the top coating (TC) near the TC/TGO interface.TGO thermal growing makes the Mises equivalent stress of the bond coating (BC) increase at the TGO/BC interface,which enhanced the probability to occur plasticity;TGO thermal thickening cannot affect the stress distribution of the alloy material of the vane.%为了获得氧化层增厚对热障涂层残余应力的影响规律,在前期采用热流耦合方法研究热障涂层温度场的基础上,考虑温度相关的热障涂层各层材料特性,分析了多循环、氧化层(TGO)热生长以及蠕变累积作用下涂层的残余应力.结果表明:经过50个热循环后,氧化层厚度在叶片尾部高温区域最大;当TGO厚度大于2 μm时,TGO厚度越大,陶瓷面层内靠近界面附近的最大主应力增量越大,易导致陶瓷面层在界面附近出现断裂失效.TGO热生长还造成靠近氧化层/粘结层的界面区域内粘结层的Mises等效应力增大,致使粘结层再次进入塑性屈服的可能性增大;TGO热生长对导叶合金材料应力分布的影响可以忽略.
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