真实TGO界面形貌对热障涂层界面应力的影响

Effect of real TGO interface topography on interface stress of thermal barrier coatings

采用MSC.MARC有限元分析软件,以真实服役的某重型燃气轮机透平第一级动叶片表面热障涂层为研究对象,研究真实TGO界面形貌对热障涂层界面应力的影响。结果表明:在TC/TGO界面的TC层中,法向应力σ_(22)分布中的拉应力位于波谷区域,压应力位于波峰区域,而在BC/TGO界面的BC层中,σ_(22)应力分布与TC层相反;TC层与BC层的剪切应力σ_(12)分布规律相同,均是波谷左侧的应力方向为负,波谷右侧的应力方向为正。TGO界面的波峰和波谷处的法向应力σ_(22)值随TGO厚度的增大而增加;当TGO厚度不变时,BC/TGO界面振幅增大,TGO内和BC内的法向应力σ_(22)值也随之增大。

Effect of real thermally growth oxide(TGO)interface topography on interface stress of thermal barrier coatings on the surface of first-stage blade of a heavy-duty gas turbine was studied by using finite element analysis software MSC.MARC.The results show that in the top coat(TC)layer at the TC/TGO interface,the tensile stress in normal stressσ_(22) is located in the trough area,and the compressive stress is located in the peak area;while in the bond coat(BC)layer at the BC/TGO interface,theσ_(22) stress distribution is opposite to that of the TC layer.Theσ_(12) stress distribution of the BC layer is the same as that of the TC layer,the distribution of shear stressσ_(12) in the TC layer is that the stress direction on the left side of the trough is negative,and that on the right side is positive.The normal stressσ_(22) at the peak and trough in the TGO increases with the thickness increase of the TGO;and when the thickness of TGO is constant,with the increase of the amplitude of the BC/TGO interface,theσ_(22) stress in TGO and BC increases.