Fig. 4: Corrosion morphology characterization for LT and HT CS Cu after immersion.

a1, 2, c1, 2, and e1, 2 SEM images of LT CS Cu corroded under NA, AS, and AC conditions, respectively. b1, 2, d1, 2, f1, 2 SEM images of HT CS Cu corroded under NA, AS, and AC conditions, respectively. g, h μCT characterization of the LT and HT CS Cu under NA conditions. Dark contrast areas in g and h in the interior of the materials are voids originally present. Red dashed lines indicate either PPIs (for LT CS Cu) or cavities (for HT CS Cu) in the high-magnification SEM images.