Fatigue of as-extruded 7005 aluminum alloy

Tensile and fatigue properties of as-extruded 7005 aluminum alloy were measured in this study. The tensile properties were obtained at two different strain rates and deformed microstructures of tested specimens were observed as well. Effects of inclusion particles and/or second phase particles on the fatigue life of 7005 aluminum alloy are discussed. Increasing particle count decreases the fatigue life of rotating bending tested samples. Dynamic recrystallization had been observed from both samples subjected to monotonic tensile loading and cyclic loading. Relation between stress amplitudes and cycles to failure has been established, and the cycles to failure at two levels of stress amplitudes as well. The probability of failure, 10-90%, at these two specific stress amplitudes was also analyzed. Finally, this study offered the predicted fatigue strength at 10⁷ cycles with different probabilities.