Acceleration corrosion factor for fatigue critical components based on the dfr: modeling and analysis

To evaluate the fatigue property for aircraft structures in corrosive environment, accounting for the influence of pre-corrosion under ground parking, the analysis of acceleration corrosion factor for accelerated aging test to service or natural exposed environment based on the Detail Fatigue Rating(DFR) of fatigue critical components is performed. Under the assumption that the pre-corrosion fatigue life follows the two-parameter Weibull distribution, the relationship between the DFR and the corrosion time is found, and the expression for acceleration corrosion factor are established. The acceleration corrosion factor is verified to be independent on the corrosion time. The approximate distribution of acceleration corrosion factor estimator is gained, so the confidence intervals of acceleration corrosion factor for LY12CZ aluminum alloys specimen are obtained.