AC Corrosion Characteristics of Cable Aluminum Sheath in 3.5% NaCl Solution

In recent years, corrosion of the aluminum sheath of cables had been discovered in coastal areas. In order to study the corrosion process of the cable aluminum sheath under the action of alternating current, the perforation time of the aluminum sheath was measured when the outer sheath was damaged in 3.5% NaCl solution, and the change of the surface corrosion morphology of the aluminum sheath was recorded at the same time when different alternating currents passed. The results showed that the perforation time of the aluminum sheath of the cable was inversely proportional to the current flowing out of the surface of the aluminum sheath. The corrosion rate was proportional to the current density flowing out of the surface of the aluminum sheath; pitting morphology appeared in the early stage of corrosion, and the pits were more dense near the center of the hole. As time went by, severely corroded area spread to the edge.