TOPOLOGICAL ASPECTS OF IRON CORROSION IN ALKALINE-SOLUTION BY MEANS OF SCANNING FORCE MICROSCOPY (SFM)

The formation and growth of microcrystalline corrosion centers on poli shed iron surfaces are studied in the initial stages by scanning force microscopy (SFM). The corrosion process is controlled by cyclic volta mmetry in 1M aqueous NaOH. The results concerning electrochemical aspe cts correspond to the literature. The in situ technique allows the obs ervation of the crystal growth processes during corrosion. The formati on of a surface layer overgrowing the initial structures caused by mec hanical pretreatment has been found. Additionally defined polyhedral c rystals were obtained with increasing number of cylic voltammograms.