Corrosion behavior of aluminum-boron composites in aqueous chloride solutions

A study has been made of the corrosion behavior of diffusion bonded 2024 aluminum alloy-unidirectional boron filament composites in aqueous chloride solutions. Compared with the 2024 alloy, the composites suffer greater localized corrosion, both in the presence and absence of applied stress, when the environment is in contact with transverse section surfaces (i.e. surfaces containing exposed boron filament ends and diffusion bonds). The electrochemical behavior of such surfaces indicates that the lowered corrosion resistance is not due to galvanic action between the filament and matrix, but results from an increase in the number of anodic sites, the latter being associated with the filament-matrix interfaces and the diffusion bonds between the alloy foils.