Photoelectrochemical monitoring of rouging and de-rouging on AISI 316L. (15th February 2017)

• Record Type: Journal Article
• Authors: Di Franco, F.; Santamaria, M.; Massaro, G.; Di Quarto, F.
• Is Part Of: Corrosion science. Volume 116(2017)
• Page Start: 74
• Page End: 87
• Publication Date: 2017-02-15
• Subjects: A. Stainless steel -- B. Cyclic voltammetry -- B. EIS -- C. Anodic films -- C. Passive films -- C. Photoelectrochemistry; Corrosion and anti-corrosives -- Periodicals; 620.11223
• DOI: 10.1016/j.corsci.2016.12.016
• Languages: English
• ISSNs: 0010-938X

Abstract

Highlights: Electrochemical conditions for inducing rouging on surface of AISI 316L are studied. Passive films were characterized by Photocurrent Spectroscopy and EIS measurements. Etching in citric acid at 60 °C for rouging removal was successfully tested. The use of Mott-Schottky model for passive films on SS is critically discussed in this paper. Abstract: Electrochemical conditions for inducing rouging on surface of AISI 316L in quasi neutral aqueous solution are studied. Potentiostatic polarization at 0.6 V vs. SSC at pH ∼ 7 allowed growth of colourless passive films with a band gap slightly lower than that estimated for the oxide grown on the SS surface by air exposure due to chromium dissolution. Under stronger anodic polarization ( U E = 1.5 V vs. SSC) coloured passive films are formed, mainly constituted by iron oxide according to their band gap ( E g = 2.0 eV). Etching in citric acid at 60 °C results to be effective in removing rouging.