The behavior of aluminum and zinc alloys were evaluated and compared as sacrifice anodes in cathodic
protection of aluminum NV-5083 hulls in seawater in Valparaíso bay. Samples of the aluminum alloy used to manufacture
boat hulls and Al-Zn-In, Al-Zn-Sn, and Zn anodes were made. Electrochemical behavior was evaluated by means of
polarization curves and corrosion potential as function of time. In parallel, galvanized pairs (boat hull-sacriice anode),
were designed and immersed in the electrolyte for 16 days, determining the weight loss and evolution of the open circuit
potential for each material. The results show that the aluminum based anodes provide the NV-5083 aluminum hull cathodic
protection in seawater. However, they do not exceed the economical horizon and useful life of zinc anodes, because the
aluminum based anodes present higher corrosion for the protection of a similar exposed area of aluminum.
Keywords: corrosion, catodic protection, sacrifice anode, galvanic couple, seawater.