功能梯度热障涂层热震表面裂纹

作为发动机热端部件上使用的功能梯度热障涂层，其热震性能的好坏直接关系到涂层的使用寿命，涂层内部的裂纹在热震环境下的变化是影响其热震性能乃至使用寿命的直接因素。采用YSZ与NiCrCoAlY等离子喷涂制备了功能梯度热障涂层试样，采用扫描电子显微镜对不同次数热震后的涂层表面不同位置进行了观察比较。结果表明，随试样位置及热震次数的不同，表面裂纹存在显著不同；除主裂纹外，会产生二次裂纹；主裂纹与二次裂纹的宽度存在差异。

Thermal Shock Cracks on the Surface of Functional Graded Thermal Barrier Coatings

Functional graded thermal barrier coatings are an important component in the engine. The property of thermal shock resistance determines the life of the coatings. The propagation of cracks in the coatings will affect the property of thermal shock resistance of coatings even the life of the coatings. In this paper, surface cracking of PSZ/NiCrCoAlY graded coating were observed by scanning electron microscope (SEM).The result shows that the cracks on the surface of coatings though different times of thermal shocks. And the cracks are distinct in the different positions of the coatings surface. The premier cracks and secondary cracks were observed on the surface of coatings.