AZ31镁合金电镀前处理工艺研究  

PRETREATMENT FOR ELECTROPLATING OF MAGNESIUM ALLOY

作　　者：王步美[1] 薛烽[1,2] 孙扬善[1,2] 贾春萍[1] 陶卫建 

机构地区：[1]东南大学材料科学与工程学院,南京211189 [2]江苏省镁合金材料工程技术研究中心,南京211221

出　　处：《中国腐蚀与防护学报》2009年第1期24-29,共6页Journal of Chinese Society For Corrosion and Protection

基　　金：江苏省自然基金预研项目(BK2004208)

摘　　要：采用扫描电子显微分析、失重实验等手段和方法探讨AZ31镁合金电镀前处理工艺。结果表明,采用CrO_3+Fe(NO_3)_3+KF酸洗后试样表面光亮,基本无失重;采用H_3PO_4+NH_4HF活化,可有效去除试样表层氧化物,增强基体和浸锌层的结合力;采用硫酸盐浸锌工艺可获得致密的浸锌层。通过分析温度、电流密度、pH值对浸锌层的影响规律,获得了最佳的浸锌工艺:30g/L ZnSO_4·7H_2O,150 g/L K_4P_2O_7·10H_2O,7 g/L KF, 5g/L Na_2CO_3,温度70℃～75℃,pH=10.2～10.4,浸锌时间10 min。在此前处理基础上电镀锌,镀层和基体结合力较好。The pretreatment techniques for AZ31 magnesium alloy has been studied by methods such as SEM, weight loss test and so on in this paper. The results show that the sample has bright surface and no weight loss after acid pickling in the solution of CrO3＋Fe（NO3）3＋KF. Oxide can be removed effectively after activation in the solution of H3PO4＋NH4HF, while adhesion ability of latter zinc immersion coating to substrate can be enhanced. A consistant and adherent coating by sulfate zinc immersion can be obtained. By researching the effect of temperature, current density and pH on the zinc immersion coating, the optimistic zinc immersion technique was determined, which is 30 g/L ZnSO4.7H2O, 150 g/L K4P2OT·10H2O, 7 g/L KF, 5 g/L Na2CO3, T=70 ℃ -75 ℃, pH=10.2-10.4, t=10 min. The adhesion of coating to the substrate is excellent after zinc electroplating after pretreatment.

关 键 词：镁合金 电镀 前处理 浸锌 

分 类 号：TQ153.2[化学工程—电化学工业]