The difference in anti-corrosion effect between the addition of La and Ce of a B10 alloy

Microalloying with rare earth elements is an effective method to improve the corrosion resistance of Cu-Ni alloys. The study of the effect of different rare earth elements on the corrosion resistance and corrosion behavior is significant for the optimization of Cu-Ni alloy composition. In this paper, the effect of La and Ce on the corrosion behavior of B10 alloy in 3.5 wt% NaCl solution was investigated separately, utilizing both electrochemical techniques and surface characterization methods. The results indicate that B10-0.1%La alloy and B10-0.1%Ce alloy have better corrosion resistance performance compared to Cu-10Ni alloy in NaCl solution. The better corrosion resistance performance of the B10-0.1%La and B10-0.1%Ce alloy could be mainly attributed to the preferential deposition of rare-earth oxides that promotes heterogeneous nucleation of the passive film. Furthermore, the deposition degree of La2O3 is greater than that of Ce2O3 during the early stage of immersion which leads to the superior corrosion resistance of the B10-0.1%La alloy.