Prediction of corrosion fatigue crack growth rate in alloys. Part I: General corrosion fatigue model for aero-space aluminum alloys

In this work, a General Corrosion Fatigue Model (GCFM) was developed for predicting corrosion fatigue crack growth rate (CFCGR) in metals under cyclical loading. The GCFM is based on an equation for the potential drop from the external surface to the crack tip of metals as derived from the principle of differential aeration. Development of the GCFM involves consideration of cyclic loading on the CFCGR and of advection between the in-crack and external environment. We demonstrate the influence of corrosion environment and cyclic loading on the crack growth rate in Al-Li alloys in a 1:1 electrolyte (0.6 M NaCl).