Preparation and characterization of Ce-sealed Ni-P coating for a nickel-based superalloy

Nickel-based superalloys have been applied in many occasions due to perfect performance. The corrosion behaviors of such alloys always occur under actual service conditions, which seriously affect their normal service. In order to improve corrosion resistance of such alloys, Ce-sealed Ni-P coating was prepared. Ni-P coating and Ce-sealed Ni-P coating were compared through three-dimensional microscopic morphology and electrochemical measurements. The effects of rare earth on corrosion resistance of Ni-P coating were discussed. The results showed that Ce-sealed Ni-P coating possessed the excellent corrosion resistance. Ce-sealing in rare earth solution reduced the surface roughness of film layer, achieving a good sealing effect.