以硫酸镍为主盐的环保型镁合金化学镀镍工艺  

Environmental Electroless Nickel Plating Technology on Magnesium Alloy in Solution with NiSO_4 as Main Salt

作　　者：沟引宁[1] 黄伟九[1] 陈文彬[1] 谈国峰[1] 薛燕[1] 

机构地区：[1]重庆理工大学材料科学与工程学院,重庆400050

出　　处：《腐蚀与防护》2010年第3期225-228,共4页Corrosion & Protection

基　　金：重庆市教委科技研究项目(KJ070602)

摘　　要：采用磷酸+钼酸铵为前处理酸洗液配方,以硫酸镍为主盐,研究了AZ91D镁合金表面直接化学镀镍工艺。运用正交试验优选了镀液中各主要组分的最佳含量。采用扫描电子显微镜观察镀层的表面和截面形貌;在3.5%NaCl溶液中进行静态腐蚀试验,采用失重法计算镀层的腐蚀速率;对镀层结构进行X射线衍射分析。结果表明,最佳工艺参数为:NiSO4.6 H2O25 g/L,NaH2PO2.H2O30 g/L,乳酸15 ml/L,镀速为26μm/h;化学镀镍层为非晶态结构;采用优化工艺得到的Ni-P镀层均匀、致密,无明显缺陷,硬度达546 HV,镀层的腐蚀速率仅为0.76μm/h。Using H3PO4 ＋ （NH4）6Mo7O24 · 4H2O as pickling solution and NiSO4 · 6H2O as main salt, the environmental direct electroless Ni-P plating technology on AZ91D magnesium alloy was investigated. The optimal contents of main compositions in electroless NiP plating bath were determined by orthogonal test. The surface and cross-section morphology of the electroless Ni-P coating were observed by using SEM. The structure of the coating was analyzed by X-ray difraction. The results showed that the electroless nickel deposits on magnesium alloys under the optimal technological conditions were amorphous, and compact without obvious defects. The micro-hardness of Ni-P coatings was 546 HV and the deposition rate was about 26 um/h. The corrosion rate of the NiP coating in 3.5% NaCl solution for 14 h was only 0. 76 um/h.

关 键 词：镁合金 化学镀镍 前处理 硫酸镍 

分 类 号：TG174.44[金属学及工艺—金属表面处理] TQ153.12[金属学及工艺—金属学]