Introducing a low-cost tool for 3D characterization of pitting corrosion in stainless steel

Herein, we propose an approach to three-dimensional (3D) reconstruction of corroded samples to have access to information about the shape, diameter, volume, depth, and spatial distribution of pits. For this purpose, a 304 stainless steel sample, after exposure to controlled corrosion conditions, was submitted to a sequence of polishing, surface image acquisition, and sample thickness measurement. This allows the 3D reconstruction of the sample using computational tomography. The analyses of the two-dimensional and the reconstructed three-dimensional images made it possible to evaluate all the geometric parameters of the pits as well as to compare these data with the electrochemical measurements recorded during the corrosion process.