Electrochemical Modeling of Anodic Metal-Rich Primers

NAVAIR has developed a new type of primer based on metallic pigments designed to drive the potential of the underlying alloy below the pitting potential, eliminating pitting and stress corrosion cracking. Although aluminum alloy-pigment primers have been developed and tested, their further development and optimization is inhibited by the lack of any way to design them efficiently or predict their properties.This project will develop computational models and distill the design method into a form usable by M&P engineers and design teams. Al-rich primers will be modeled using Siemens Star CCM+ Computer-Aided Engineering (CAE) software. Micro-scale modeling will include particle morphology, chemistry and loading, and the electrochemical effect of particle surface treatments such as TCP. The effect of ionic conduction in the electrolyte-saturated polymer matrix will be taken into account using a multi-ion model. At the macro-scale the electrical polarization, electrochemical impedance, etc. will be used to model and predict the electrochemical (corrosion-mitigating) performance of the coating on assemblies of alloy and composite components.To make it possible for engineers to use this modeling approach without being CAE experts, Simulation Assistants will be created to make the modeling approach accessible to M & P engineers and the design community.