Lap joints of aging aircraft exhibit serious corrosion due to its crevice structure. A novel model was developed for crevices in aluminum alloys with no large outside cathodes. The most distinguishing difference between lap joint crevice corrosion and conventional crevice corrosion lies in lack of a large outside cathode for a lap joint. Both oxidation and reduction must take place within the lap joint, in contrast to the dominant reduction that occurs at the large outside cathode for conventional crevice corrosion. The possible applications of the model include lap joint corrosion of aircraft, automobiles and building structures.
Keywords: crevice corrosion, aluminum alloys, mass transfer, lap joint