Study on the galvanic corrosion behavior of copper-nickel/titanium alloys under simulated seawater environment.

Titanium alloys have broad application prospects in the field of marine engineering due to their excellent corrosion resistance and comprehensive mechanical properties. Titanium alloys, when connected with other metals, such as copper-nickel alloys, could produce two distinct effects. On the one hand, the passive film gives titanium alloys positive potential, which could accelerate galvanic corrosion of negative-potential metals. On the other hand, the passive film could obstruct current flow and prevent further development of galvanic corrosion. In this paper, Potentiodynamic Polarization, Electrochemical Impedance Spectroscopy, and Electrochemical Noise techniques were utilized to investigate the galvanic corrosion behavior of B10/Ti80 under simulated seawater environment. The corrosion morphology and product composition were studied using Scanning Electron Microscope and X-ray Photoelectron Spectroscopy. The above experimental results showed that Ti80 and B10 served as the anode and cathode respectively in the early stages of corrosion (within 2.5 h of immersion), due to the incomplete formation of the passivation film on Ti80. While in the latter stages of corrosion, due to the positive shift of Ti80's potential by passivation, there was a noticeable accelerated corrosion effect on B10, which was proportional to the area ratio of Ti80/B10 and showed a gradually stable trend after 28 days of immersion in the seawater. [ABSTRACT FROM AUTHOR]