涡轮叶片热障涂层三维成像研究进展

热障涂层是涡轮叶片高温防护关键技术,具有典型的层状结构特征,且热障涂层服役过程中高温氧化产生热生长氧化物结构,迫切需要利用三维成像方法无损探知热障涂层内部结构。由于计算机断层成像技术能提供三维立体图像,准确再现物体内部三维结构,是热障涂层层状结构最佳分析手段之一,在热障涂层喷涂质量评价和高温氧化监测方面具有很好的前景。重点介绍了国内外在热障涂层微米CT成像、同步辐射CT成像、聚焦离子束–扫描电镜(FIB–SEM)三维成像及热应力有限元仿真方面的进展。最后指出了热障涂层无损检测可能的发展方向。

Research Progress on Three-Dimensional Imaging of Thermal Barrier Coatings for Turbine Blade

Thermal barrier coatings(TBCs)is a key technology of high temperature protection of turbine blade,which has typical layered structure characteristics.Thermally grown oxide(TGO)is produced by high temperature oxidation during the service of the thermal barrier coatings,and there is an urgent need for three-dimensional imaging method which will detect the internal structure of thermal barrier coatings nondestructively.Because three-dimensional images can be obtained by computed tomography(CT),and the three-dimensional structure of the object can be reproduced accurately,it is one of the best analysis methods for the layered structure of thermal barrier coatings,and has a good performance in thermal barrier coatings spraying quality evaluation and high temperature oxidation monitoring.In this paper,the development of micro-CT imaging,synchrotron radiation CT imaging,3D imaging of focused ion beam–scanning electron microscope(FIB–SEM)and thermal stress finite element simulation of thermal barrier coatings in domestic and abroad are mainly introduced.Finally,the possible development direction is pointed out.