On the microstructure and corrosion behavior of Fe-28.5Ni steel subjected to severe plastic deformation

This study investigates the influence of the Accumulative Roll-Bonding (ARB) process on the corrosion behavior of Fe-28.5Ni alloys. The research examines how the ARB as a severe plastic deformation technique alters the microstructure and corrosion resistance of this alloy. Specimens subjected to different ARB cycles were analyzed using electrochemical impedance spectroscopy, cyclic potentiodynamic polarization, and open-circuit potential measurements in 1M HCl solution. Results indicate that increasing the number of ARB cycles initially decreases corrosion resistance due to higher dislocation densities. However, after four cycles, the formation of low-angle grain boundaries enhances corrosion resistance by creating a more uniform surface energy distribution and stable corrosion product layers. Optimal corrosion resistance was observed at six ARB cycles, beyond which high-angle grain boundaries began to diminish the protective effects. This study underscores the significance of optimizing ARB parameters to improve the performance of Fe-Ni alloys in corrosive environments.