Bondline Corrosion Properties of ARALL in Salt Spray Environment

摘要

Long term environmental tests on ARALL are summarized. No severe bondline corrosion is encountered up to 519 days of salt spray exposure. The peel strength of the adhesives continuously decreases with increasing exposure. After 519 days of exposure, losses of 30% to 50% in peel strength can be expected. No bondline corrosion is expected if all pretreatments are carefully executed. The appearance of an adhesive interface is favorable for ARALL compared with monolytic materials. If corrosion appears (and it is very hard to prevent any corrosion), the adhesive acts as a barrier and only a limited area is affected in contradiction with monolithic materials where through tickness corrosion is dangerous. Because of its composition (fibers as adhesive), the prepreg used in ARALL is a superior barrier compared with pure adhesives.