Galvanic corrosion of Ti6Al4V -AA2024 joints in aircraft environment: Modelling and experimental validation

Abstract

This study focuses on the development of a physico-chemical model based on mechanistic and kinetics understanding of the corrosion process in galvanic couple Ti6Al4V-AA2024. Proposed model provides deeper insights at macro level for initiation and propagation of localized corrosion of AA2024 in galvanically coupled multi-material assemblies. The model is able to reveal the localized corrosion, related to heterogeneity of AA2024 microstructure, including local pH changes, the deposition of the reaction products, and emphasizes the important role of AA2024 self-corrosion in galvanic assemblies. The validation of the developed model was performed using relevant data collected by advanced in situ localized techniques.