摘要:课题详细阐述了以三价铬为主要成分,辅以无机阴离子或稀土元素等物质组成的镀锌钝化液。采用单因素法和烧杯实验结合的方法,研究了钝化液中各种组成、操作条件对钝化膜外观、附着力及耐腐蚀性的影响。研究得到最佳三价铬蓝白色钝化液成分及操作条件为:氯化铬6g/L,硝酸钠3g/L,氟化钠0.5g/L,751水合氯化钴0.25g/L,pH为2.5、温度30℃、钝化时间30s。所获得的膜层外观呈均匀光亮的蓝白色;附着力性能良好,用无砂橡皮轻擦6次方至蓝白色钝化膜层脱落露出镀锌层;膜层能耐中性盐雾试验48h以上,表明镀锌层表面经钝化后能大大增加锌镀层对基体的保护性。在此次课题研究过程中,不难发现三价铬蓝白色钝化膜耐腐蚀性能还可以进一步进行提高。32852
毕业论文关键词: 镀锌层;三价铬;蓝白钝化
Study of the trivalent chromium passivation about blue and white at room temperature on the surface of the galvanized layer
Abstract:Topics in detail elaborated the trivalent chromium as main ingredients, supplemented by inorganic anion or galvanized passivation solution composed of materials such as rare earth elements.By using the combined method of single factor method and the beaker experiment, studied the various composition of passivation solution, operation conditions, the appearance, adhesion and corrosion resistance of passivation film.Research on optimal trivalent chromium passivation solution components and operating conditions for the blue and white:CrCl3•6H2O 6g/L,NaNO3 3g/L,NaF 0.5g/L,CoCl2•6H2O 2.5g/L,pH 2.5, temperature 30℃, 30s passivation time.The uniform appearance of the film obtained is light blue and white;Good adhesion performance, wipe gently with no sand rubber power 6 to blue-white passivation film falls off with galvanized layer;Membrane layer ability more than 48 h salt spray test, shows that the galvanized layer surface after passivation can greatly increase the protection of zinc coating to the substrate.In the process of the research, it is not difficult to find that the corrosion resistance of trivalent chromium passivation film blue and white can also be further improved.
Keywords: zinc coating;Trivalent chromium;Blue and white passivation
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 1
1.3 课题在国内外研究的情况及发展趋势 2
1.4 课题主要的技术要求 3
2三价铬钝化膜形成的技术原理 4
2.1三价铬转化膜的形成机理 4
2.2 钝化膜的耐蚀性 5
2.3 钝化膜的颜色 5
3工艺研究方法 6
3.1 工艺研究方法 6
3.2 钝化膜的性能测定、试验方法 6
3.2.1钝化膜外观检测 6
3.2.2钝化膜的附着力检测 6
3.2.3钝化膜的耐腐蚀性 6
4实验研究 8
4.1 实验仪器、试剂、材料 8
4.1.1 主要仪器和材料 8
4.1.2 主要试剂 8
4.2 镀锌层的制备 8
4.2.1 镀液的配制 8
4.2.2添加剂的配制 9
4.2.3 钝化用试片的电镀 9
4.3 钝化膜的制备 10
4.3.1 钝化液的配制 10
4.3.2 钝化膜的制备 10
5试验结果及讨论 11
5.1 试验结果 11
5.2 工艺成份的作用与影响 11
5.2.1 氯化铬 11
5.2.2 硝酸钠 12
5.2.3氟化钠 13 镀锌层表面的常温三价铬蓝白钝化工艺研究:http://www.751com.cn/huaxue/lunwen_29638.html