图1描绘了浸泡期间不同时间从盐溶液中取出的纯锌的表面。在浸泡长达6小时后，样品仍然具有金属光泽(图1a)。然后金属光泽消失了。虽然在浸泡24小时和48小时后样品上有严重的腐蚀迹象，但这是因为在浸泡过程中悬挂样品以保持其垂直的金属丝。可以看出，在浸泡长达120小时后，样品表面出现局部发白的腐蚀产物。随着浸泡时间的延长，腐蚀产物增加，这可能是由于腐蚀产物在浸泡过程中不断沉淀(图1e和h)

Fig. 1 portrays the surface of pure Zn taken from saline solution at different time during immersion. The samples still had metallic luster shortly after immersion up to 6 h (Fig. 1a). Then the metallic luster disappeared. Although there is severe corrosion sign on the samples immersed after 24 h and 48 h, it was because of the wire which hanged the samples to keep it vertical during the immersion. It is can be seen that localized whitish corrosion product appears on the sample surface after immersion up to 120 h. With the extension of immersion time, the corrosion products increased, which could be attributed to the corrosion products precipitated continuously during immersion (Fig. 1e and h).