飞行状态下热障涂层的受力行为

本文通过在计算机中建立航空发动机叶片的工作环境,进而模拟在飞行状态下叶片表面涂敷的陶瓷热障涂层的受力行为,获得了陶瓷涂层在热气动载荷作用下应力场分布,并得出应力场分布与涂层结构和叶片几何形状及与承受的载荷之间的关系,提出了进一步提高陶瓷热障涂层的使用寿命的途径。

THERMAL STRESS ANALYSIS OF CERAMIC THERMAL BARRIER COATING UNDER LOADING

The computer simulation of ceramic thermal barrier coating(TBC) on turbine engine blades during loading process has been conducted.The results show that coating's thermal stress is directly affected by loading's status i.e.,higher level and rapidly changing loading produce larger thermal stress value.Blade shape plays an important role in thermal stress distribution.Blade's back side has the largest stress value, while blade exhaust edge has the lowest.The stress concentration zone along blade surface usually occures at the place where curvature is changed.These results suggest that some measures to move stress concentration zone from ceramic layer to bond coating or to substrate should be taken, and choosing bond coating which is easy to slip during thermal expansion may increase the life and reliability of TBC.