Homogenization pretreatment and electroless Ni-P plating on AZ91D magnesium alloy  

AZ91D镁合金的均一化前处理与化学镀Ni-P(英文)

作　　者：孙灿[1] 郭兴伍[1,2] 王少华[1] 郭嘉成 丁文江[1,2] 

机构地区：[1]上海交通大学轻合金精密成型国家工程研究中心,上海200240 [2]上海交通大学金属基复合材料国家重点实验室,上海200240

出　　处：《Transactions of Nonferrous Metals Society of China》2014年第12期3825-3833,共9页中国有色金属学报（英文版）

基　　金：Project(51371116)supported by the National Natural Science Foundation of China;Project(2009AA033501)supported by the Ministry of Science and Technology,China

摘　　要：Electroless nickel plating on AZ91D substrate with a new and eco-friendly pretreatment process based on tuning an electrochemical homogeneous surface was investigated. The morphology, deposition process, chemical composition and microstructure of Ni-P coating were studied. It is indicated that β phases are selectively removed, producing a microstructural homogeneous surface and the subsequent uniform and compact Zn immersion layer. A defect-free and well adhesive Ni-P coating can be successfully obtained due to its uniform nucleation and growth based on such pretreatment. Potentiodynamic polarization and electrochemical impedance spectroscopy （EIS） tests reveal that Ni-P coating could significantly improve the corrosion resistance of AZ91D substrate.采用新型环保的均一化前处理工艺在AZ91D镁合金表面制备了化学镀Ni-P镀层。研究了前处理过程中AZ91D基体微观形貌、镀层沉积过程、成分和相结构。研究结果表明:基体表面的β相在前处理过程中被选择性去除,表面组织得到均一化,从而获得均匀致密的浸Zn层。Ni-P颗粒均匀形核生长,并最终形成致密的镀层。镀层具有优良的耐腐蚀性能。

关 键 词：AZ91D magnesium alloy homogenization pretreatment electroless nickel plating CORROSION 

分 类 号：TG178[金属学及工艺—金属表面处理]