为修复某航空叶片损伤,在单层多道激光熔覆的基础上,研究了多道多层激光熔覆的可行性。每层粉末成分渐变,分析了熔覆层金相组织,测试了熔覆层显微硬度及其在大气环境室温下的干滑动磨擦磨损性能。结果表明:熔覆层和基体呈现良好的冶金结合,白亮结合带宽度为10～20μm;熔覆层组织由粗大疏松的柱状晶过渡为细小、致密的枝晶;熔覆层显微硬度最高达到425HV,比基体高出40%～50%;熔覆层的磨损量比基体减少约3～4倍。

To repairing the damage of a aero blade,an experiment of multilayer cladding based on monolayer cladding had been carried out. The components of each layer are gradually changed. The microstructure of the clad layer was investigated. The microhardness was measured. The friction and wear properties of the clad layer in air environment were examined. It was found that the clad layer was well combined with the substrate. The white narrow metallurgical bonding zone was about 10～20μm. The structure of the clad layer was transitted from bulky and loose columnar grain to exiguous and compact dendritic crystal. The microstructure of the clad zone increased to 425HV,40%～50% higher than that of the substrate. The rate of wear was 3～4 times lower than that of the substrate.