[Article] Differential aeration corrosion of silver in sulfate melts at 900 ◦C

Abstract

The thermodynamic of the Ag/Ag2SO4 electrode, serving as reference for carrying electrochemical experiences of corrosion in sulfates at 900 ◦C, was investigated because of the observed limited operating lifetime. Its use led to the total degradation of the ∅1 mm Ag wire in ~200 h. Half-immersion of Ag wires in sulfates mixes (selected for their acido-basicity) evidenced the homogeneous thinning of the immersed part of the wires and the precipitation of metallic Ag in the salt. The different steps governing the corrosion mechanism were proposed considering that the driving force was the differential aeration of the Ag wire.

Differential aeration of the silver wire between its anodic part (A) immersed in sulfate and its cathodic part (C) emerged.

Authors :
D. Diomande, S. Mathieu, P.J. Panteix, M. Siblani, L. Aranda, C. Petitjean, M. Vilasi

References :
Corrosion Science 224 (2023) 111504
 
DOI :
https://doi.org/10.1016/j.corsci.2023.111504