气膜冷却孔是航空发动机涡轮叶片上的重要冷却结构，激光可以在涡轮复杂曲面上制备出高精度气膜孔。激光作用过程中产生的重铸层会降低气膜冷却效果。 虽然超快激光通常视为“冷”加工，但大功率高重频的超快激光也会出现热损伤。 激光加工气膜孔技术的重点是多方面的 , 重铸层形成机理及其抑制方法是激光加工气膜孔技术的重点之一。 目前对激光加工气膜孔重铸层的研究集中于加工参数的影响。 激光加工气膜孔重铸层的研究已经取得了一定的成果，但是尚未解决重铸层形成机理问题。 从重铸层的金相组织、元素组成等方面对重铸层进行表征分析是一种可能的研究方向，介绍激光加工气膜孔的加工原理与现状，并对激光加工微孔时重铸层的相关研究进行综述，总结了目前关于重铸层形成机理的相关理论研究。

Film cooling holes are important cooling structures on aero-engine turbine blades. Lasers can fabricate high-precision film cooling holes on complex turbine surfaces. The recast layer produced during laser machining will reduce the cooling effect. Although ultrafast lasers are usually regarded as “ cold ” processing, thermal damage can also occur in high-power and high-repetition rate ultrafast lasers. The focus of laser processing film cooling hole technology is multifaceted, and the formation mechanism of the recast layer and its inhibition method are key points of laser processing film cooling hole technology. At present, research on laser processing of the recast layer of film cooling holes focuses on the influence of parameters. Some achievements have been made in the research of laser processing of the recast layer of film cooling holes, but the formation mechanism of the recast layer has not yet been solved. It is possible to characterize and analyse the recast layer from its metallographic structure and element composition. This paper introduces the processing principle and status of laser processing of film cooling holes. Then, it summarizes the relevant research on the recast layer of microholes and finally the current theoretical research on the formation mechanism of the recast layer.