Galvanic corrosion occurs when two electrochemically dissimilar metals are in direct electrical contact while immersed in a conductive marine seawater electrolyte. In accordance with the galvanic series, the more electronegative metal acts as a sacrificial anode (such as zinc), spontaneously oxidizing and releasing cations into the seawater. This electron flow polarizes the cathodic structural steel hull cathodically, suppressing iron oxidation and preventing hull degradation.