镁合金复合镀层的制备及其结构与性能表征  

Study on the Structure and Properties of Composite Coating on Magnesium Alloy

作　　者：党在清 DANG Zaiqing(Shanxi vocational college of engineering,tanghuai campus,xinzhou 030000,China)

机构地区：[1]山西工程职业学院唐槐校区,山西忻州030000

出　　处：《电镀与精饰》2020年第11期16-19,共4页Plating & Finishing

摘　　要：以AZ91D镁合金为基体材料,采用有机涂膜预处理后,化学镀Ni-P、电镀Ni,制备了有机涂膜/Ni-P/Ni三层复合镀层。利用SEM、XPS、EDS等检测方法,电位动力学极化曲线研究了镀层可靠性及耐腐蚀性。结果表明:有机涂膜/Ni-P/电镀Ni复合镀层维氏硬度达到355 HV,复合镀层的临界破坏载荷Fc为91 N;镀镍后镁合金自腐蚀电位提高了0.869 V,腐蚀电流从1.24×10^-4 A/cm^2,降低至1.26×10^-6 A/cm^2,自腐蚀电流密度较基体降低了两个数量级,表明镀层在静态腐蚀浸泡实验中具有较好的耐腐蚀性能。Three-layer composite organic coating/Ni-P/Ni was prepared on AZ91D magnesium alloy by spray pretreatment,electroless plating and electroplating nickel.The reliability analysis and corrosion resistance of coatings were investigated through SEM,XPS,EDS and potential kinetic polarization curve test method,respectively.The results show that the zinc pretreatment can make the coating more smooth and uniform.The vickers hardness of Ni-P/Ni composite coating can reach 355 HV.The critical failure load of composite coating is about 91 N.The corrosion potential of the magnesium alloy after nick⁃el plating has increased 0.869 V.Furthermore,the corrosion current is reduced from 1.24×10^-4 A/cm^2,to 1.26×10^-6 A/cm^2,and the self-corrosion current density is reduced by two orders of magnitude com⁃pared to the substrate,indicating that the coating has better corrosion performance in the static corrosion immersion experiment.

关 键 词：镁合金 预处理 复合镀镍 结合强度 

分 类 号：TG174.4[金属学及工艺—金属表面处理]