Multiphysics research on the growth mechanism of oxide films during iron anodic oxidation

Given the critical significance and multi-field coupling complexity of anodization process parameter optimization, this study guided iron anodization experiments through simulation to accurately identify the optimal parameters. A finite element analysis approach was employed, and a coupled electrochemical-mass transfer model was established using COMSOL Multiphysics software to systematically investigate the effects of system potential distribution, current density, and oxidation time on oxide film growth, thereby screening out the optimal parameters. The results indicate that the oxide film thickness is positively correlated with electrolyte potential and current density, and there are significant differences in the electrolyte potential variation patterns under different voltages. The simulation results confirm that 50 V is the optimal applied voltage balancing film growth rate and uniformity, and reveal the growth kinetic characteristics of the oxide film and the multi-field coupled negative feedback mechanism during iron anodization. This research provides precise experimental guidance and a theoretical basis for the efficient and controllable preparation of oxide films on iron-based materials.