Potentiodynamic polarization curves of AA7075 at high scan rates interpreted using the high field model

This study investigates the distortion of potentiodynamic polarization (PDP) curves of AA7075 aluminum alloy measured at high scan rates. The authors measured PDP curves at various scan rates (0.167 mV s⁻¹ to 100 mV s⁻¹) in acidic (0.62 M NaH₂PO₄) and near-neutral (3.5 wt% NaCl) solutions. Contrary to previous studies attributing distortions to charging currents, the authors find that the high field model, which incorporates anodic oxide growth kinetics, best explains the observed changes in PDP curves across different scan rates, electrolytes, and experimental replicates. The high field model successfully captures the changing kinetics with scan rates, electrolytes, and the variance between measurements.

Hu Zhou, Danny Chhin, Alban Morel, Danick Gallant, Janine Mauzeroll