摘要本文采用化学镀镍的方法在镁合金基底上分别制备了Ni-P合金镀层和Ni-La-P合金镀层，并探究了两种镀层的工艺条件，较佳工艺条件分别为：吐温-80作为表面活性、酸洗液浓度400ml/L、酸洗浸渍60s、活化时间10min、La(NO3)3添加量0.035g/100ml、镀液pH值8.5、镀液温度74℃、化学镀时间60min，在该条件下分别制得的Ni-La-P合金镀层耐蚀性比Ni-P合金镀层耐蚀性提高了45.7%。62208

利用EDX、SEM、XRD测试方法分别对Ni-P、Ni-La-P合金镀层的微观形貌、成分、物相结构进行了表征。EDX结果表明，分别获得了Ni-P合金镀层和Ni-La-P合金。SEM结果表明，Ni-La-P合金镀层比Ni-P合金镀层结瘤变大，表面平整度有所降低。XRD结果表明，Ni-P合金镀层和Ni-La-P合金镀层的镀层晶型结构分别都为Ni12P5四方晶型。

创新点：

在未经高温的条件下制备出Ni-La-P合金晶体镀层，达到了经高温处理得效果。目前在未经高温条件下制备出Ni-La-P合金晶体镀层的文献未有报道。

毕业论文关键词：镁合金；化学镀镍；Ni-P层；晶体；镧 

Abstract

In this paper, a method of electroless nickel plating on magnesium alloy substrate were prepared Ni-P alloy plating layer and Ni-La-P alloy coating, and explores two kinds of coating process conditions, the preferred conditions are as follows: Tween-80 as the surfactant, the concentration of the acid lotion 400ml / L, pickling dipping 60s, activation time 10min, La (NO3)3 addition amount of 0.035g / 100ml, pH value 8.5, bath temperature 74 ℃, plating time of 60min, under this condition were obtained Ni-La-P alloy corrosion resistance than the Ni-P alloy coating improves the corrosion resistance of 45.7%.The use of SEM, EDX, XRD Test Methods for Ni-P, morphology of Ni-La-P alloy coating, composition, phase structure were characterized. SEM results show that compared with Ni-P alloy coating, Ni-La-P alloy coating of nodules increases, surface roughness decreased. EDX results showed were given a Ni-P alloy plating layer and Ni-La-P alloy. XRD results showed that the prepared coating structure Ni12P5 tetragonal crystal structure, and adding La(NO3)3 after, La3+ into the lattice.Innovation:

Chemical nickel plating method without the high temperature-treated conditions for preparing a Ni-La-P alloy crystal coating. Document is currently under high temperature conditions without the preparation of Ni-La-P alloy crystal coating has not been reported.

Keywords: magnesium alloy; electroless nickel plating; Ni-P layer; crystal; lanthanum 

目  录

1引言.1

1.1 金属涂层..1

1.1.1渗镀1

1.1.2气相沉积1

1.1.3化学镀和电镀1

1.1.4热镀2

1.2镁合金防腐技术..2

1.2.1改善成分或研发新合金2

1.2.2改变微观结构2

1.2.3镁合金基底表面处理3

1.3镁合金防腐未来发展方向..4

1.4镁合金镀镍防腐技术..4

1.4.1 工艺..4

1.4.2复合镀层5

1.4.3 镀层后处理..5

1.5研究内容..6

2实验部分7

2.1实验材料及试剂..7

2.1.1实验材料..7

2.1.2 实验试剂..7

2.2 实验装置与设备8

2.2.1 实验装置.8

2.2.2 实验设备.8

2.3 工艺过程9

2.3.1 镀前准备9

2.3.2镀液准备.9

2.3.3镀前预处理10

2.4  工艺条件筛选12

2.4.1表面活性剂的选择12

2.4.2 酸洗浓度选择12

2.4.3酸洗浸渍时间选择12

2.4.4 活化时间选择12

2.4.5La(NO3)3添加量选择.12

2.4.6镀液pH值选择选..12

2.4.7 镀液温度选择.12

2.4.8化学镀时间选择.13

2.5镀层性能的测试及表征13.

2.5.1点滴试验.13