Affiliation: | aEMBRAER (Empresa Brasileira de Aeronáutica), Av. Brigadeiro Faria Lima 2170, 12227-901 São José dos Campos, SP, Brazil bCVRD (Companhia Vale do Rio Doce), Av. Dante Michelini, 5500, 29090-900 Vitória, ES, Brazil cUniversidade Federal de Ouro Preto, Escola de Minas, Deptartamento de Engenharia Metalúrgica e de Materiais, Praça Tiradentes 20, 35400-000 Ouro Preto, MG, Brazil |
Abstract: | In this study, 7475-T7351 aluminum strips were subjected to two tensile pre-strain levels of 3% and 5%. Using compact tension C(T) specimens, fatigue crack growth tests were conducted under constant amplitude loading at stress ratios of 0.1 and 0.5 in air and at room temperature. Three fatigue crack growth rate (FCGR) models, namely, Collipriest, Priddle, and NASGRO were examined. To handle the effect of stress ratio on FCGR, Walker equivalent stress intensity factor model was used. Consequently, generalized Collipriest (GC), generalized Priddle (GP), and generalized NASGRO (GN) models were developed and fitted to the FCGR data. It was shown that both GC and GP models fit the FCGR data in a similar fashion. However, the GP model provided a better fit than the GC model. The GN model was found to be the most appropriate model for the data. Therefore, this model may be suggested for use in critical applications, such as aeronautical structural design. |