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锌层表面的常温三价铬彩色钝化工艺研究

时间:2018-12-27 21:15来源:毕业论文
六价铬钝化和三价铬钝化是目前应用最为广泛的镀锌层钝化工艺。但是六价铬是有毒物质,不仅会污染环境,并且对人的身体健康有非常大的危害。所以三价铬钝化工艺是电镀厂的首选

摘要:六价铬钝化和三价铬钝化是目前应用最为广泛的镀锌层钝化工艺。但是六价铬是有毒物质,不仅会污染环境,并且对人的身体健康有非常大的危害。所以三价铬钝化工艺是电镀厂的首选工艺。三价铬钝化的膜层与六价铬钝化膜层有许多相似之处,但是其毒性仅是六价铬的1%。阐述了镀锌层在常温下得到三价铬彩色钝化膜的工艺。采用单因素实验法研究了钝化液的组份各自用量、操作条件对钝化膜外观的影响,采用中性盐雾试验测定了钝化膜层的耐腐蚀性。通过试验研究得到了三价铬彩色钝化工艺:三氯化铬为29.2g/L,硫酸钠为24g/L,氟化铵为1.2g/L,硝酸钠为12g/L,pH值2.5,钝化温度为30℃,钝化时间为60s。在该工艺中能获得的钝化膜表面光亮,呈彩虹色,允许有轻微雾;膜层与基底有良好的附着力,膜层的中性盐雾试验为72小时以上。32013
毕业论文关键词:钝化;三价铬;镀锌
Study on temperature of trivalent chromium passivation technology of zinc layer surface
Abatract: Six valence chromium passivation and trivalent chromium passivation is one of the most extensive passivation process. But six chromium is a toxic substance, not only pollute the environment, and human health have very great harm. So the trivalent chromium passivation process is the preferred plating plant. The film of trivalent chromium passivation and six valence chromium passivation film have many similarities, but its toxicity is only six chromium 1%. This paper discusses the process of galvanized layer of trivalent chromium passivation film at room temperature. Using single facto. Using single factor experiment method and the optimization method, and study the influence of composition of the passivation solution of the respective dosage and operating conditions on the passivation effect. Through optimization experiment, trivalent chromium passivation process has been. By neutral salt spray test determination of the corrosion resistance of the film, through friction polishing experiments, determination of coating adhesion. Finally obtained plating surface was a rainbow color, the surface layer of the mask to look bright, light fog, the film and the substrate has good adhesion, film in neutral salt spray test for more than 72 hours, in accordance with the requirements of the project.

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KeyWords: passivation; trivalent chromium; galvanized
目录
1  引言    1
1.1 课题的概况及研究意义    1
1.2 课题研究的内容及目的    2
1.3 课题在国内外研究的情况及发展趋势    3
1.4 课题主要的技术要求    4
2  三价铬钝化的技术原理    5
2.1 三价铬钝化机理    5
2.2 三价铬钝化膜和六价铬钝化膜外观比较    7
2.3 三价铬钝化膜外观的影响因素    7
2.3.1三价铬钝化剂组成及影响    7
2.3.2 钝化工作液pH值、钝化温度、浸渍时间影响    8
2.3.3 钝化膜干燥温度的影响    8
2.3.4杂质的影响    9
2.3.5 其他因素的影响    9
3  工艺研究方法    11
3.1工艺研究方法    11
3.2各项性能测定、试验方法    11
3.2.1钝化层性能试验方法    11
4  实验研究    13
4.1实验仪器和试剂    13
4.2镀锌层制备    13
4.2.1氯化钾镀锌溶液的配制    13
4.2.2电镀    13
4.3试片的钝化    13
4.3.1 钝化液的配制    13
4.3.2 试片的钝化    13
4.4 钝化层腐蚀性能检测    14 锌层表面的常温三价铬彩色钝化工艺研究:http://www.lwfree.cn/huaxue/20181227/28401.html
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