热镀锌钝化板锌花形貌对耐蚀性的影响

采用光学显微镜和扫描电子显微镜(SEM/EDS)对热镀锌钝化板锌花形貌及不同时间中性盐雾试验后热镀锌钝化板锌花的腐蚀形貌进行了分析,研究了热镀锌钝化板表面形态、微区成分及锌花形貌对其耐蚀性的影响.结果表明,热镀梓板有典型的锌花形貌,明亮和灰暗锌花区的形貌差异大;灰暗锌花区无规则密布的球形颗粒为Pb及Al元素的富集,光亮锌花区平整性良好,较少元素富集;明亮锌花区的耐蚀性明显优于灰暗锌花区,腐蚀在球形颗粒处优先发生,由颗粒处向整个锌花区域扩展.

Effect of Spangles Morphology on Corrosion Resistance of Passivated Hot Galvanizing Plate

Morphologies of passivated hot galvanizing plate before and after neutral salt spray corrosion test in various times were analyzed by optical microscopy and SEM/EDS,and the effects of surface morphologies,micro-zone components and spangle appearance on its corrosion resistance were studied.Results show that hot galvanizing plate has typical spangle appearance,and the appearances distinguish in bright zone and gray zone.There are irregularly dense ball particles that are rich of Pb and Al elements,but the bright spangle zone is smooth with less elements richened.The corrosion resistance of bright zone is obviously excelled than gray zone.Corrosion is priority on the ball particles and then developing to whole spangle zone.