Preparation of High Corrosion Resistance Ni-Fe-Sm Alloy Films in Reline System

Abstract

In order to solve the problem of rough surface and poor corrosion resistance of Ni-Fe alloys prepared in traditional aqueous electrolytes, the Ni-Fe-Sm ternary alloy membranes are prepared by adding rare earth element Sm to modify Ni-Fe alloy from choline chlorine-urea ionic liquid system (Reline). Through cyclic voltammetry, Tafel test, scanning electron microscope and X-ray energy spectrometer, respectively, the electrochemical behavior of metal ions in Reline ionic liquid, the surface morphology of alloy film and resistance corrosion performance are studied. The results show that Ni(II) and Fe(II) are one-step irreversible reduction processes, and the nucleation mechanism of Ni-Fe-Sm alloy in Reline system is three-dimensional instantaneous nucleation. The metal elements on the surface of the Ni-Fe-Sm alloy film are evenly distributed, and the microstructure is nodular spherical particles. The surface of the alloy film is fine, with few cracks and neat arrangement. In 3.5 wt.%NaCl and 10 wt.%HCl solutions, adding rare earth element Sm, the corrosion resistance of the alloy film is significantly improved. When the deposition potential is −1.22 V and the deposition time is 20 min, the self-corrosion current density is the lowest, the corrosion rate is the lowest, the self-corrosion potential is the most positive, and the corrosion resistance is the highest. This paper further enriches the understanding of adding rare earth elements to the Reline system to improve the corrosion resistance of alloys, making it have better application prospects in the fields of protection and storage.