AZ91D镁合金表面激光熔覆Al+Al_2O_3涂层研究  

Laser surface cladding of AZ91D magnesium alloy with Al+Al_2O_3 powders

作　　者：杨晓飞[1] 林文光[1] 毛广雷[1] 

机构地区：[1]内蒙古工业大学材料科学与工程学院,内蒙古呼和浩特010051

出　　处：《兵器材料科学与工程》2007年第4期20-23,共4页Ordnance Material Science and Engineering

摘　　要：为了改善AZ91D镁合金的表面性能,试验利用3kW横流CO2激光器在AZ91D镁合金表面上进行了激光熔覆Al+Al2O3涂层处理。熔覆后使用X射线衍射仪(XRD)和扫描电镜(SEM)对熔覆层进行了微观分析,测试了熔覆层的显微硬度及摩擦磨损性能。试验结果表明:熔覆层由Mg,Mg17Al12,Al2O3等相组成,表层微观结构主要是Mg和Al的亚共晶基体及其上弥散的Al2O3颗粒;熔覆层的平均显微硬度最高达到250HV0.05,明显高于基体AZ91D(70～80HV0.05);其磨损性能与基体相比也有了较大提高。The laser surface cladding of AZ91D magnesium alloy with Al＋Al2O3 powders was investigated. Laser processing was carried out with a 3 kW CO2 continuous wave laser gear. The detailed microstructure and phase analysis of the modified layer were carried out by XRD and SEM. The micro-hardness and the wear properties of the layer were investigated. It was found that the surface layer was composed of phases of Mg, Mg17Al12, Al2O3. The microstructure of the modified layer consisted of dispersion of Al2O3 particles in the hypoeutectic matrix of Mg and Al. The microhardness of the surface layer was significantly improved to as high as 250 HV0.05,much higher than that of the AZ91D substrate （70-80HV0.05）. The wear resistance of the laser modified samples was considerably improved as compared to the matrix.

关 键 词：镁合金 激光熔覆 涂层 显微硬度 磨损 

分 类 号：TG175.3[金属学及工艺—金属表面处理]