Corrosion resulting from electric current flow between dissimilar metals is called:

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When two different metals are in electrical contact in the presence of a conductive liquid, they form a galvanic cell and the current flow causes one metal to corrode while the other is protected. The metal with the more negative electrochemical potential acts as the anode and dissolves into the solution, while the more noble metal serves as the cathode. The faster the corrosion, the bigger the potential difference and the larger the area of the corroding metal relative to the protected metal. To prevent this, keep dissimilar metals from touching, insulate joints, or coat surfaces; in some designs you can use a sacrificial anode to take the corrosion load. This is distinct from electrolysis, which is general decomposition driven by current in a solution, stray current corrosion from external DC sources, and oxygen starvation corrosion, which arises from limited oxygen in a system rather than from dissimilar metal coupling.