Thin Foil Penetration Technique at a Local Scale: Towards an Analysis of the Current Transients during Intergranular Propagation on AA2024 Alloy

A local electrochemical probe was combined with the thin foil penetration technique to study the corrosion propagation of a reduced number of grain boundary traces (in-plane) propagating inside a 60 mu m thick foil of AA2024. This local and ``in-volume'' approach allowed analysis of the current transient resulting from the full penetration of the selected intergranular paths. By coupling a 2D spatially resolved electrochemistry to digital optical observation on the back side of the foil, it was possible to relate the current transient to the successive steps of the ``in-volume'' propagation of intergranular corrosion. (C) The Author(s) 2019. Published by ECS.