| Steel plate must have a passivating treatment after hot galvanizing, the manufacture was delayed by undesirable passivating results, which were caused by unreliable performance of passivator. The performance was determined by the composition and structure of the passive films, so the composition and properties of films were studied.Patterns of original passivator were observed by SEM and TEM, patterns of galvanizing sheet were observed by SEM, the surface of galvanizing sheet was smoothed with less defects. EDS analysis showed that Znic,Oxygen,Chromium,Carbon were contained in the surface films. AES analysis showed elements' distribution in depth, the content of all elements but zinc decreased while thickness of films increased. There were Cr,O,C,Zn,P,N,F,Si in films ,which were detected by XPS technique, they existed in films as CrPO4,Cr(OH)3,CrOOH,Cr2O3,CrO3,ZnO,Zn(OH)2,Zn3(PO4)2,H2O,NH3,organic molecule and silica sol. Adhesive power test showed S1 is better than T1. S1 showed good corrosion resistance during anodic polarization. NSS results showed S1 was best than others. According to all the results, chemical reactions which might happen in passivating treatment were inferred. It was deemed the films' formation supported phase-forming theory. It was found that corrosion resistance of passive films were influenced by the use level of...
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