Abstract

The present paper is focused on the corrosion of austenitic (AISI304) and a Duplex (2205) stainless steel grades in H2O/KOH 50% at 120°C. Linear sweep voltammetry and electrochemical impedance spectrometry measurements were carried out with an AMEL modified potentiostat equipped with a digital FRA in an home-made cell for high-temperature work with gas control. The impedance spectra have been fitted with a novel numerical model. The experiments were complemented by metallographic (in-plane and cross-sectional SEM micrography), structural (X-ray diffractometry) and compositional (EDX line-profiles) characterization of the materials attacked under electrochemically controlled conditions. Electrochemical measurements have shown that AISI304 exhibits a passivating behaviour, with a secondary peak in the passive range and eventual transpassivity. Duplex electrochemical behaviour is characterized by a mixed kinetic control. AISI304 was found to fail by intergranular corrosion and to be covered in passive conditions by acicular compounds and in transpassive conditions by a compact layer of corrosion products. Duplex samples, instead, exhibits a more uniform surface morphology and a compact layer of corrosion products both in passive and in transpassive conditions.

Autore Pugliese

• Bozzini Benedetto , Scarselli Gennaro

Tutti gli autori

• B. Bozzini , F. Bogani , G. Giovannelli , S. Natali , G. Scarselli , M. Boniardi

Titolo volume/Rivista

MATERIALS AND CORROSION

Anno di pubblicazione

2013

ISSN

0947-5117

ISBN

Non Disponibile

Numero di citazioni Wos

Nessuna citazione

Ultimo Aggiornamento Citazioni

Non Disponibile

Numero di citazioni Scopus

Non Disponibile

0

Ultimo Aggiornamento Citazioni

22/04/2018

Settori ERC

Non Disponibile

Codici ASJC

Non Disponibile