The corrosion behavior of Fe-Co-Si alloy under magnetic field

The advanced soft magnetic material Fe-Co-Si ternary alloy has become a research hotspot in recent years due to its excellent balanced magnetic properties. When used in an environment where oceans and magnetic fields interact, the corrosion behavior of this alloy is currently not well understood. In this study, immersion experiments and electrochemical tests have been used to explore its corrosion behavior under conditions of no magnetic field, a uniform parallel magnetic field, and a vertical magnetic field with a magnetic field. The results indicate that the presence of a magnetic field accelerates corrosion while suppressing pitting and intergranular corrosion of the alloy. Moreover, compared to the perpendicular magnetic field, the impact is more pronounced when applying a parallel magnetic field due to the synergistic effect of Lorentz force and magnetic field gradient force. Additionally, the presence of Si elements affects the formation of Co oxide passivation film, which reduced the corrosion resistance of the alloy under both magnetic and non-magnetic field conditions. This finding contributes to filling the theoretical gap in the corrosion failure behavior of Fe-Co-Si alloy under magnetic field conditions.