Electrodeposition of Fe-nano-Si particle composite coatings in a perpendicular static magnetic field

Fe-Si composite coatings were prepared by nano-composite electroplating in a static magnetic field parallel to the electrode surface. The effects of magnetic flux density and current density on the cathode current efficiency and silicon content in the coatings were studied. The coatings were characterized by scanning electron microscopy and energy dispersive spectrometry. It is found that the cathode current efficiency first increases and then decreases with increasing magnetic flux density. The mass fraction of silicon in the coatings reaches its maximum value of 20. 17% at 0. 2 T, which increases by 10. 4% compared with that without any magnetic field. In addition, the smooth surface morphology of the coatings turns into "mountain ranges", whose directions are the same to the direction of magnetohydrodynamic convection (MHD). More and longer "mountain ranges" appear with increasing magnetic flux density. Owing to MHD effect, the magnetic field also influences the surface morphology of hydrogen pores and promotes the evolution of hydrogen.