为了提高等离子喷涂Al2O3-13%TiO2(质量分数)陶瓷涂层的抗热震性能,采用激光重熔工艺对涂层进行处理,研究了激光重熔对等离子喷涂层热震性能的影响,并探讨了涂层的热震失效机理。结果表明:相对于等离子喷涂试样,激光重熔涂层有较好的抗热震性能。等离子喷涂陶瓷涂层的热震失效形式基本为边角剥落,而激光重熔陶瓷涂层热震失效形式既有边角剥落又有相当数量的中间区域局部剥落。激光重熔对涂层热震性能的影响主要表现为降低涂层的初始抗破坏能力、减缓涂层的裂纹扩展速率以及改变涂层的破坏模式。
In order to improve the thermal shock resistance of Al2O3-13 %TiO2 (mass fraction) ceramic coating prepared by plasma spraying, laser remelting experiment was carried out and the influences of laser remelting on thermal shock behavior on the plasma-sprayed coating were researched. Meanwhile, the thermal shock failure mechanisms of the coatings were discussed. The results showed that as a result of thermal shock experiments at 850℃, the laser-remelted coating had better thermal shock resistance than the plasma-sprayed coating. The failure mechanism of the plasma-sprayed coating was corner spalling. In contract, the failure mechanism of the laser-remelted was mainly corner spalling, as well as local pelling. The effects of laser remelting on thermal shock behavior of the as-sprayed coating are mainly as follows., decrease the initial thermal shock resistance of the coating, slowdown the formation of crack in coating and change the coating's failure mode