Environmentally-assisted Fatigue Crack Growth in AA7050-T73511 Al Alloy and AA2050-T84 Al-Cu-Li Alloy
Moreto, Jéferson Aparecido, Paschoal Júnior, Fernando Antônio, Maciel, Carla Isabel Santos, Bonazzi, Luis Henrique Camargo, Leonelli Júnior, José Francisco, Ruchert, Cassius Olívio Figueiredo Terra, Bose Filho, Waldek Wladimir
DATA DE PUBLICAÇÃO
The aim of this study was to evaluate and compare the effect of low temperature and saline environment on the fatigue crack growth behavior of the AA7050-T7451 Al alloy and the recently developed AA2050-T Al-Cu-Li alloy. Fatigue at room and low temperature and corrosion-fatigue tests were carried out using an applied stress ratio (R) of 0.1, 15 Hz frequency (air at RT and –54 °C) and 1 Hz frequency (seawater fog) using a sinusoidal wave form. In the near-threshold region, in air and at RT it was found a ΔKth = 2.9 MPa.m1/2 for AA2050-T84, in saline environment this value increased to ΔKth = 4.9 MPa.m1/2, due to closure effect through wedge effect by the corrosion products. At the beginning of the Paris-Erdogan region, the crack closure effect was not present for the AA7050-T7451, but persisted for the AA2050 Al-li alloy. It was observed that both alloys were equally affected by temperature reduction. When the saline environment is considered it was observed that the AA7050-T7451 presents lower m value (2.6) than the one for AA2050-T84 (3.4), meaning a lower FCG rate variation with ΔK, however it presented the highest C value, as a consequence the worst FCG behavior.
- Occurrence of Defects in Laser Beam Welded Al-Cu-Li Sheets with T-Joint Configuration
- Microstructural evolution of AA7050 al alloy processed by ECAP
- Effect of Interrupted Ageing and Retrogression-Reageing Treatments on Fatigue Crack Growth with a Single Applied Overload in 7050 Aluminum Alloy
- Microstructure evolution of AA7050 Al alloy during Equal-Channel Angular Pressing
- Correlação entre variáveis térmicas de solidificação, microestrutura e comportamento mecânico de ligas Al-Zn e Al-Cu-Li.