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Early stages of tin bronze corrosion in neutral aqueous chloride media: Electrochemical and FTIR investigations
Author(s) -
Aouadi S.,
Souissi N.
Publication year - 2016
Publication title -
materials and corrosion
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.487
H-Index - 55
eISSN - 1521-4176
pISSN - 0947-5117
DOI - 10.1002/maco.201608856
Subject(s) - chloride , dissolution , tin , corrosion , alloy , aqueous solution , bronze , inorganic chemistry , electrochemistry , activation energy , chemistry , enthalpy , electrolyte , fourier transform infrared spectroscopy , materials science , metallurgy , chemical engineering , electrode , engineering , physics , quantum mechanics
The corrosion behavior of tin bronze alloy equivalent to a Punic one was investigated in aqueous 0.5 M chloride electrolyte using potentiodynamic measurements. The electrochemical results showed selective dissolution of the major alloy component reflecting a decuprification process. FTIR characterization of the patina anodic layers showed the presence of various dehydrated and hydrated tin compounds with a few copper species suggesting the patina type I formation on the Cu10Sn bronze alloy. A kinetic model for the Cu10Sn bronze alloy dissolution in the chloride solution was developed. The reaction order with respect to chloride content was determined for the Cl − halide concentration domains. The low order value (about 0.22) was attributed to the Cl − adsorption intermediate step. The high reaction order value (about 2) reflected two determining steps of cuprous chloride complex formation. Two behaviors for the material were evidenced when varying the temperature. The values of the activation energy Ea, activation enthalpy Δ H * and activation entropy Δ S * were calculated and discussed.