节点文献
镀锌层的硅酸盐无铬钝化研究
Silicate-Based Passivation Technique on Alkaline Electrodeposited Zinc Coatings
【作者】 林萍；
【导师】 范云鹰；
【作者基本信息】 昆明理工大学 ， 材料物理与化学， 2010， 硕士
【摘要】 为了减少电镀业使用铬酸盐所造成的环境污染,本文研究了用于碱性镀锌层蓝白钝化的新型无铬钝化液工艺配方。该钝化液以硅酸盐为主要原料,并含有双氧水和氟离子等物质。采用正交优化与单因素优化相结合的方法,讨论硅酸盐型钝化液各组分对镀锌层钝化膜的影响。并且对镀锌硅酸盐钝化工艺技术进行了系统的研究,讨论了钝化液成分、钝化温度、钝化时间、钝化液pH值、空停时间、活化时间、出光时间对钝化成膜及膜层耐蚀性的影响。钝化液的组成及工艺条件为：Na2Si03·9H2 18g/LHNO3 15ml/LZnSO4·7H2O 28 g/LNaF 2.4g/LH2O2 10ml/L钝化时间20spH值2-3钝化温度25℃空停时间0-1s活化时问25s出光时间5s干燥条件热风吹干实验材料为碱性电镀锌钢板,用上述溶液钝化后,通过中性盐雾试验(NSS试验),硫酸铜点滴试验,盐水浸泡试验及电化学测试等方法对该硅酸盐钝化样品的耐蚀性进行了研究,并通过扫描电镜及XPS对钝化膜进行表征。研究表明,该硅酸盐钝化工艺可在镀锌层表面得到光泽度好、耐蚀性高的蓝白色钝化膜,可代替传统铬盐钝化工艺从而解决其环境污染问题,具有良好的应用前景。
【Abstract】 In order to reduce the environmental pollution caused by the electroplating industry in use of chromate salt, this paper studies a novel chromium-free passivating liquid technological formulation used for bright blue passivation of alkaline galvanized layer. This passivating liquid takes silicate as main raw materials and contains substances such as hydrogen peroxide, fluorin ion and others. Using the method of combining orthogonal optimization and single factor optimization, the impact of all the components of Silicate type passivation liquid upon galvanized layer passivation membrane is discussed. Besides, the systematic research on galvanized silicate passivation technology is carried on, and the impact of passivation solution composition, passivation temperature, passivation time, passivation solution pH value, time of pause, Activation time, glaring time upon the passivation membrane and membrane layer noncorrodibility. Passivation solution composition and process conditions is as the followed:Na2SiO3·9H2O 18g/LHNO3 15ml/LZnSO4·7H2O 28 g/LNaF 2.4 g/LH2O2 10ml/LPassivation Time 20 spH Value 2-3Passivation temperature 25℃Time of pause 0-1 sActivation time 25 sGlaring time 5 sDry conditions Blowing drywith Hot airExperimental material is an alkaline electricity galvanized steel plate. After the above mentioned solution is passivated,the noncorrodibility of this silicate passivation samples has been researched by way of neutral salt spray test(NSS test), acid copper dropping test, salt water immersion test and electrochemical test, etc. and the passivation membrane is characterized by scanning electron microscope and XPS.The research shows that by this silicate passivation technology bright blue passivation membrane with good gloss and high noncorrodibility can be acquired in the surface of galvanized layer, which can replace traditional chrome salt passivation technology so as to solve the problem of environmental pollution, and has good application prospect.