Fatigue crack formation and growth from localized corrosion in Al–Zn–Mg–Cu

The Effect of Pitting on Fatigue Lives of Peak-Aged and Overaged 7075 Aluminum Alloys

“…This may be the reason for nonconformity of predicted and observed fatigue lives. [27] Kim et al [25] have tried to enhance the capability of the EIFS analysis by including certain assumptions about the crack initiation and growth, but the change in gross material property has not been considered. The effect pitting has on strength properties is quite significant; the tensile mechanical properties as well as fracture toughness were found to decrease exponentially with corrosion exposure in 2024 alloys.…”

“…[37,40] Studies have also been carried out with precorroded specimens that were subsequently subjected to cyclic loading. [20,25,27] With regard to aircrafts, it is more probable that the pitting and fatigue events are temporally distinct. Pitting is likely to occur when the aircraft is grounded, while fatigue would occur under a variable spectrum loading situation in flight; pit to crack transition would also occur in flight.…”

“…[22][23][24] Predicting remaining fatigue life of corroded components or samples has been the subject of various studies. [25][26][27][28][29][30][31] Some researchers [26][27][28][29][30][31] had adopted a fracture mechanics approach to life, adapted to the case of pits serving as the initial flaws. Ghidini et al [22] suggested a probabilistic model to predict fatigue life of 2024-T3 aluminum alloy using fracture mechanics methods.…”

Effects of Prior Corrosion with and Without Stress on the Mechanical Properties of 7475-T761 Aluminum Alloy

“…High-strength aluminum alloy mainly suffers localized corrosion such as pitting corrosion, intergranular corrosion and exfoliation corrosion in the corrosive environment [1,2]. The localized corrosion decreases the load-carrying capacity of the aluminum structure, and fatigue crack would appear easily at the corrosion defect, thus reducing the fatigue strength of the aluminum [3][4][5][6]. When exposed to corrosion and tensile stress, stress corrosion cracking would occur in high-strength aluminum alloy [7][8][9].…”

Crack Initiation from Corrosion Pit in Three Aluminum Alloys Under Ambient and Saltwater Environments

“…Corrosive attack can be from the plain water, saltwater, or water vapor containing salt particularly in a marine environment or in several geographic areas. Previous studies have shown that the fatigue life decreases and fatigue crack growth rate increases under the corrosive environment (Ref [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15]. Damage initiates in the form of a pit under a corrosive environment.…”