Effect of Loading Frequency on Corrosion Fatigue Crack Growth Rate of Aerospace Aluminum Alloy

A corrosion fatigue crack growth rate model considering the effect of loading frequency for LC aluminum alloy was established based on a concept of corrosion fatigue frequency factor proposed by author. Verification test for the established model was carried out. Results indicate that an exponential expression of corrosion fatigue frequency factor is reasonable to reflect the influence of loading frequency on corrosion fatigue crack growth, and corrosion damage will significantly reduce the threshold value of fatigue crack growth. The prediction of crack growth rate based on the proposed model was proved to be in good agreement with experimental results for steadily extended corrosion fatigue crack, indicating that the proposed model is of reference value for the corrosion fatigue life prediction of aero aluminum structure.