Photoelectrochemical monitoring of rouging and de-rouging on AISI 316L
- Autori: Di Franco, F.; Santamaria, M.; Massaro, G.; Di Quarto, F.
- Anno di pubblicazione: 2017
- Tipologia: Articolo in rivista (Articolo in rivista)
- Parole Chiave: A. Stainless steel; B. Cyclic voltammetry; B. EIS; C. Anodic films; C. Passive films; C. Photoelectrochemistry; Chemistry (all); Chemical Engineering (all); Materials Science (all)
- OA Link: http://hdl.handle.net/10447/223271
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 (UE = 1.5 V vs. SSC) coloured passive films are formed, mainly constituted by iron oxide according to their band gap (Eg = 2.0 eV). Etching in citric acid at 60 °C results to be effective in removing rouging.