Innovative Approaches for Predicting Galvanic Effects of Dissimilar Material Interfaces

The current approach to airframe design is to select materials and structures for mechanical and thermal load performance based upon initial properties. The reality is that environmental influences cause materials to degrade over time, coatings and paint systems are applied to slow down this degradation. However, the coatings themselves eventually degrade or are damaged in service. Areas of inadequate protection or high galvanic activity cannot usually be identified until the design is completed and fielded. In Phase 1 we successfully demonstrated that the FEA approach to galvanic corrosion prediction is a sound method and delivers excellent qualitative results on corrosion locations and relative severity. The current GalvanicMaster software is an excellent prediction tool for the initial corrosion state when used with metallic materials, coatings and to some extent anodized layers. However, most Naval systems are protected by complex paint systems, which the software currently does not accommodate, nor does the model include the effect of corrosion product build-up on the surface. Phase 2 will fully develop the approach into a usable design and prediction tool, incorporating paint systems, coating degradation, coating damage and corrosion product build-up.