Abstract
Surface characterization and corrosion behavior of 90/10 copper-nickel alloy in seawater from Xiamen bay at 30 °C for 56 days were investigated in this study. The results indicated that the corrosion product layer was mainly a mixture of CuO, Cu2O, and Cu(OH)2, with a transition to CuCl, CuCl2, and Cu2(OH)3Cl during the corrosion process. However, as corrosion proceeds, the resistance of the product film was reduced due to its heterogeneous and fairly porous structures, which led to local corrosion of the alloy. The corrosion potentials (Ecorr) increase while corrosion current densities (Icorr) decrease with time because of the formation of protective oxide film.
Highlights
Copper-nickel alloys are generally known for their good corrosion resistance, excellent machinability, and outstanding thermal and electrical conductivity in marine environments [1,2,3]
The objective of this paper is to investigate the surface characterization and corrosion behavior of 90/10 copper-nickel alloy after two months of immersion in the mixed solution of 0.5 mol/L H2 O2 and natural seawater from Xiamen bay in China using XPS, SEM and electrochemistry technique
The results demonstrate that the corrosion product films on the surface are heterogeneous and fairly porous, as well as all present cracks and exfoliation, which are due to the compactness, high fragility, poor cohesion, and adhesion [12]
Summary
Copper-nickel alloys are generally known for their good corrosion resistance, excellent machinability, and outstanding thermal and electrical conductivity in marine environments [1,2,3]. The excellent corrosion resistance of Cu-Ni alloy is mainly due to two reasons. The ionization of copper is difficult as a result of the positive equilibrium potential and the high thermodynamic stability of Cu. Second, nickel was incorporated into Cu2 O film and increases the corrosion resistance in two ways: (i) Ni2+ occupies the vacant position of Cu+ and increase the ionic resistance, which makes two. Cu+ ions disappear and increases the ion resistance of the film; (ii) Ni2+ replaces Cu+ directly, while the ionic resistance does not change and each substitution results in the disappearance of one Cu+. Copper and copper alloys are more corrosion-resistant than other metal alloys [1]
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.