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Abstract: According to the Paris–Hertzberg crack growth law, an analytical model shows that cracks grow from a flaw very quickly from the short to the long cracks regime, during gigacycle fatigue. The location of the initiation, at the surface or inside, has a small effect. This means that the key problem is the nucleation of the crack around the flaws as it is shown by Lukas et al. and Mughrabi and Stanzl [Lukas P, Kunz L, Svoboda M, Bokuvka O. Fatigue behaviour of ultra fine-grain copper in VHCF regime. In: VHCF4, Ann Arbor; 2007. p. 265–70, ; Mughrabi H, Stanzl S. Fatigue damage evolution in ductile single phase FCC metals in the UHCF regime. In: VHCF4, Ann Arbor; 2007. p. 75–82, ]. This approach is applied to a PM Ni alloy which is used for aircraft turbine. It is concluded that the damage tolerance concept is to be applied with cautiousness for VHCF prediction, in PM alloys. [Copyright &y& Elsevier]

• Alloy AA2050-T84 presented superior behavior when tested in air and aqueous saline environments. • Electrochemical characterization results showed a superior resistance of alloy AA2050-T84 in saline environments. • AA2050-T84 showed signs of non-homogeneous deformation behavior at the crack tip. AA7050-T7451 aluminum alloy is one of the most used material in aeronautical applications due to its high strength/density ratio and good fatigue resistance. More recently the AA2050-T84 alloy was introduced due to its reduced density and comparable static mechanical properties. However, fatigue crack propagation properties in corrosive environments are yet to be documented. In this paper fatigue crack propagation was evaluated in saline (3.5 wt% NaCl solution) and air environments. The AA2050-T84 alloy presented a better fatigue performance both in air and aqueous saline environments. Its superior performance was ascribed to non-homogeneous deformation and higher corrosion resistance. These results show the AA2050-T84 alloy as a potential candidate to replace AA7050-T7451 alloy in aeronautical components subjected to fatigue in corrosive environments. [ABSTRACT FROM AUTHOR]