Corrosion mechanism of copper immersed in ammonium sulfate solution

Abstract

(NH4)2SO4 is abundant in the dust of the rural and industrial atmosphere, by which a thin layer of (NH4)2SO4 solution will be formed on the copper surface and give rise to serious corrosion as soon as the ambient humidity gets the critical relative humidity. In this work, the corrosion mechanism of copper in (NH4)2SO4 solution was studied by microgravimetry associated with SEM/EDS, FT‐IR, XRD, titration method, and electrochemical tests. The results suggest that the corrosion of copper is not only caused by electrochemical effect, but also caused by the synergistic actions of the electrochemical and chemical reactions. In addition, it is found that the presence of free Cu2+ is the prerequisite for the formation of corrosion products on copper immersed in (NH4)2SO4 solution. NH4+ plays a dual role in promoting the corrosion of copper and inhibiting the formation of corrosion products on copper surface.

The effect of chloride, sulfate, and ammonium ions on the semiconducting behavior and corrosion resistance of AISI 304 stainless steel passive film

“…Austenitic stainless steels (SS) are useful materials with many industrial applications as they are extensively used in cooling water systems [8,9] especially when ammonium is present, and the utilization of copper is not advisable [10]. Their corrosion behavior is dependent on several medium factors such as ion concentration, temperature, and water velocity.…”