Al_(2)O_(3)改性等离子喷涂-物理气相沉积热障涂层的异物损伤行为及失效机理

Foreign object damage behavior and failure mechanism of Al_(2)O_(3)-modified TBCs prepared by PS-PVD

由外来异物损伤引起的颗粒冲蚀是制约热障涂层使用寿命的重要因素。为了提高等离子喷涂-物理气相沉积(PS-PVD)热障涂层的耐冲蚀性能,采用磁控溅射和真空热处理在PS-PVD喷涂的7YSZ热障涂层表面制备一层致密的α-Al_(2)O_(3)。系统研究热障涂层的异物损伤行为,并采用第一性原理计算对α-Al_(2)O_(3)/c-ZrO_(2)界面进行研究。结果表明,PS-PVD、大气等离子喷涂(APS)和电子束-物理气相沉积(EB-PVD)热障涂层的冲蚀质量损失率分别为324、248和139μg/g,而Al_(2)O_(3)改性的PS-PVD热障涂层的冲蚀质量损失率降至199μg/g。此外,在Al_(2)O_(3)/ZrO_(2)-O的顶部构型模型中观察到的界面结合能最高(3.88 J/m^(2)),远高于ZrO_(2)/Ni(2.011 J/m^(2)),使界面结合性能得以提高。

Particle erosion induced by foreign object damage(FOD)is an important factor that restricts the working life of thermal barrier coatings(TBCs).A denseα-Al_(2)O_(3)overlay was prepared by magnetron sputtering and vacuum treatment on the surface of 7YSZ TBCs sprayed by plasma spray-physical vapor deposition(PS-PVD)to improve the erosion resistance of the TBCs.The FOD behavior of the TBCs was systematically studied and the interface ofα-Al_(2)O_(3)/c-ZrO_(2) was investigated by first principles calculations.The experimental results show that the erosion rates of the PS-PVD,atmospheric plasma spraying(APS),and electron beam-physical vapor deposition(EB-PVD)TBCs were 324,248,and 139μg/g,respectively,while the erosion rate of the Al_(2)O_(3)-modified PS-PVD TBCs was reduced to 199μg/g.In addition,the highest interface adhesive energy of 3.88 J/m^(2) observed in the top configuration model of Al_(2)O_(3)/ZrO_(2)−O is much higher than that of ZrO_(2)/Ni(2.011 J/m^(2)),which results in improved interface bonding performance.