(1. 榆林学院能源工程学院 榆林市新材料工程技术研究中心，榆林 719000； 2. 太原理工大学 材料科学与工程学院，太原 030024)
摘 要: 采用激光熔敷(Laser cladding, LC)和搅拌摩擦加工(Friction stir processing, FSP)相结合技术在AZ31B镁合金表面制备Al-Cu混合粉末的合金化涂层。采用SEM、EDS、XRD以及电化学腐蚀测试系统对Al-Cu涂层的显微组织特征、相组成以及耐腐蚀性能进行测试。结果表明：LC制备的Al-Cu涂层与基体呈良好的冶金结合，涂层主要由α-Mg、β-Al12Mg17及AlCu4组成；LC制备的Al-Cu涂层经FSP之后，涂层表面宏观成型平整光滑，表层组织均匀细化。电化学腐蚀结果发现经FSP后的Al-Cu涂层耐腐蚀性能得到明显提升，自腐蚀电位达到-0.989 V，比LC涂层的自腐蚀电位(-1.457 V)提高32.1%，比母材的自腐蚀电位(-1.563 V)提高36.7%。
关键字: AZ31B；激光熔敷；搅拌摩擦加工；显微组织；耐腐蚀性能
（1. College of Energy Engineering, Yulin Engineering Technology Research Center for Frontier Materials, Yulin University, Yulin 719000, China; 2. College of Materials Science and Engineering, Taiyuan University of Technology, Taiyuan 030024, China）
Abstract:Al-Cu powders were prepared on the surface of AZ31B magnesium alloy by a method of combining laser cladding and friction stir processing. The microstructure feature, phase component and corrosion resistance of the modified layer were studied by scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), X-ray diffractometry (XRD) and electrochemical workstation. The composite modified layers with Al-Cu powders are composed of α-Mg, Al12Mg17 and AlCu4. Both modified layers show very good bonding with the magnesium alloy substrate. The corrosion resistance of the Al-Cu coating is higher than that of the substrate. Compared with the matrix and laser cladding, the maximum self-corrosion potential (-0.989 V) with Al-Cu powders prepared by friction stir processing increases by 36.7% and 32.1%, respectively.
Key words: AZ31B magnesium alloy; laser cladding; friction stir processing; microstructure; corrosion resistance
