摘要镁合金具有高的比刚度和比强度、铸造性能好等优点，但由于化学活性极高， 导致其稳定、耐蚀、硬度等性能很差。通过对镁合金表面处理可大大改善其性能缺 陷，但现阶段的化学镀镍法工艺复杂，成本大，操作难度高。81102

为降低镁合金表面化学镀工艺的难度，本实验尝试通过镁合金先预浸镍，再直 接化学镀镍的方法，来改善镁合金的性能。本文以 AZ31 镁合金为实验材料，研究合 金表面酸洗、预处理工艺及化学镀配方。通过点滴腐蚀实验、电化学测试、SEM、XRD、 EDS、金相显微镜等方法检测镀层的耐蚀性和表观特征，与空白试样对照比较后表明 通过此方法在镁合金表面镀镍不仅可以降低实验的操作难度，而且可以很大程度提 高镁合金的硬度及耐蚀性。由于镀层中镍的含量不是很高，因此实验还有待改进。

毕业论文关键词：AZ31 镁合金；预浸镍；化学镀镍合金

Abstract Magnesium alloys have high specific stiffness and strength, good  casting performance advantages, but because of the extremely high chemical activity, leading to its stability, corrosion resistance, hardness and other poor performance。By magnesium alloy surface treatment can greatly improve the performance deficiencies, but at this stage of the complex process of electroless nickel plating method, the cost of large, high difficulty operation。

In order to reduce the difficulty of electroless plating on the surface of magnesium alloy, the experiment was tried to improve the performance of magnesium alloy by the method of electroless nickel plating on magnesium alloy first。In this paper, AZ31 magnesium alloy as material, exploring the alloy surface pickling, plating pretreatment and chemical formulations。By dropping corrosion experiments and electrochemical test, SEM, XRD, EDS, metallurgical microscope and other methods to detect the coating corrosion resistance and appearance characteristics,comparing with the blank control sample by this method showed nickel magnesium alloy surface can not only reduce the difficulty of the operation of the experiment,but also increase the hardness and corrosion resistance of magnesium alloy to a large extent。But the nickel content of coating is not very high,the experiment needs to be improved。

Key words : AZ31 magnesium alloy ; Nickel prepreg ; Electroless nickel alloys

目 录

第一章 绪 论 1

1。1 镁合金 1

1。1。1 镁合金影响因素 1

1。1。2 镁合金应用及前景 3

1。2 镁合金的防护技术及研究现状 3

1。3 镀膜检测方法 5

1。4 化学镀研究现状 6

1。5 实验研究意义及内容 7

1。5。1 实验研究意义 7

1。5。2 实验研究内容 7

第二章 实验过程及工艺 8

2。1 实验材料 8

2。2 实验流程 9

2。2。1 制样 9

2。2。2 表面预处理 9

2。2。3 预浸镍 11

2。2。4 化学镀镍 12

2。3 耐蚀性检测 13

2。3。1 浸泡实验 13