Galvanic Corrosion Risk Mapping

Galvanic corrosion is a major problem impacting aerospace platform design, retrofit, and maintenance. MIL-STD-889 provides guidance on dissimilar material selection based on the corrosion potential of materials in flowing seawater. This standard provides a general guide for materials selection, but contains a limited material database and does not account for corrosion rates in addition to corrosion potential. To better inform materials selection during design and/or retrofit, an interactive galvanic corrosion predictor tool (GCPT) has been developed that quantitatively predicts corrosion rates. The GCPT is a computational engine that predicts pitting corrosion and galvanic corrosion rates between dissimilar materials. Galvanic interactions between dissimilar materials are modeled using a curve-crossing algorithm based on the Theory of Mixed Potentials. Furthermore, the GCPT and its material database have been coupled with computer-assisted design (CAD) software to enable galvanic simulations of coating systems, sub-assemblies, and large-scale platform models. This enables designers and material and process (M&P) engineers to rapidly assess galvanic corrosion risks prior to material qualification and implementation, rather than relying solely on engineering judgment or service history.