Effects of Ni addition on corrosion behaviors of laser cladded FeSiBNi coating in 3.5% NaCl solution

FeSiBNi coatings with the Ni mass fractions of 0, 3, 6 and 9% were fabricated on S355 steel using a laser cladded (LC). The surface and cross-section morphologies, chemical compositions, phases of the obtained coatings were analyzed using a scanning electron microscope (SEM), energy dispersive spectroscopy (EDS), and X-ray diffraction (XRD), respectively. The effects of Ni addition on the immersion corrosion and electrochemical corrosion behaviors of FeSiBNi coatings in 3.5% NaCl solution were discussed. The results show that the FeSiBNi coatings with the Ni mass fractions of 0, 3, 6 and 9% are composed of crystallization phases of alpha-Fe, Fe2B and alpha-(Fe, Ni), and the corresponding amorphous contents are 7.68, 9.02, 8.87, and 9.21%, respectively. The NiO passivation film is formed by addition of Ni, which effectively improves the corrosion resistance of FeSiBNi coating. The corrosion potentials of FeSiBNi coatings with the Ni mass fractions of 0, 3, 6 and 9% are -0.788, -0.685, -0.567, and -0.529 V, respectively, exhibiting that the corrosion potential shifts positively, the corrosion resistances increase with the increase of Ni mass fractions. (C) 2019 Elsevier B.V. All rights reserved.