Electrochemical corrosion behavior of Fe64/Ni36 and Fe55/Ni45 alloys in 4.0% sodium chloride solutions

Abstract

The electrochemical corrosion behavior of two iron/nickel alloys namely, Fe64/Ni36 and Fe55/Ni45, in 4.0% NaCl solution was reported. The study was conducted using open-circuit potential, electrochemical impedance spectroscopy, cyclic polarization, and chronoamperometric current-time measurements. The surface of the alloys after 7 days immersion in the solution was investigated by scanning electron microscope and energy dispersive X-ray analyzer. It was found that the corrosion resistance for Fe55/Ni45 alloy was higher than that for Fe64/Ni36 one. This was confirmed by the low corrosion current and corrosion rate as well as the high corrosion resistance for Fe55/Ni45 compared to Fe64/Ni36 alloy. Moreover, the less negative potential and the low absolute current obtained for Fe55/Ni45 alloy by the open-circuit potential and chronoamperometric experiments, respectively.