The cyclic behavior and microstructure evolution of Ti-6Al-4V-0.55Fe alloy were investigated with three different total strain amplitudes. A slight softening was occurred with Δε_t/2 = 1.20%, and the alloy mainly suffered α recrystallization. Besides, a gentle softening can be observed with Δε_t/2 = 1.60%, which led to more substructure deformation. Furthermore, a sudden drop of the stress amplitude was occurred with Δε_t/2 = 4.00% which resulted in more plastic deformation. The phase transformation and α recrystallization were observed. Cracks were propagated along the α grain boundaries and the α/β lamellar interfaces due to the concentrated dislocations at the α/β lamellar interfaces.

用三种不同的总应变幅值研究了 Ti-6Al-4V-0.55Fe 合金的循环行为和显微组织演变。Δ ε _t /2 = 1.20%，合金发生轻微软化，主要发生α再结晶。此外，在 Δ ε _t /2 = 1.60% 时可以观察到温和的软化，这导致更多的子结构变形。此外，当 Δ ε _t /2 = 4.00% 时，应力幅值突然下降，导致更多的塑性变形。观察到相变和α重结晶。由于 α/β 层状界面处的集中位错，裂纹沿 α 晶界和 α/β 层状界面传播 。