The passive behaviour of 304 stainless steels in saturated calcium hydroxide solution under different deformation

The passive behaviour of deformed 304 stainless steel samples in saturated calcium hydroxide solution has been studied by electrochemical technologies and X-ray photoelectron spectroscopy (XPS). The passive films on seriously deformed stainless steel become heavily doped. The donor and acceptor densities increase with increasing degree of deformation. The space-charge layer is thinned as the substrate is progressively deformed. The degree of deformation has an obvious influence on the composition of Fe-II/Fe-III cations, but do not have a significant influence on the content of Cr cations. Compared with an elastically deformed sample, the passivity of a plastically deformed stainless steel is more significantly affected. (C) 2014 Elsevier Ltd. All rights reserved.