The tensile behaviour of near α Ti3Al2.5 V alloy, conceived for applications in aerospace and automotive engineering, is characterized from quasi-static to high strain rates. The material is found to present noticeable strain rate sensitivity. The dynamic true strain rate in the necking cross-section reaches values up to ten times higher than the nominal strain rate. It is also observed that beyond necking the dynamic true stress-strain curves present limited rate dependence. The experimental results at different strain rates are used to determine a suitable constitutive model for finite element simulations of the dynamic tensile tests. The model predicts the experimentally macroscopic force-time response, true stress-strain response and effective strain rate evolution with good agreement.

为航空航天和汽车工程应用而设计的近 α Ti3Al2.5 V 合金的拉伸行为具有从准静态到高应变率的特点。发现该材料具有显着的应变率敏感性。颈缩截面中的动态真实应变率达到比标称应变率高十倍的值。还观察到除了颈缩动态真实应力-应变曲线呈现有限的速率依赖性。不同应变率下的实验结果用于确定适合动态拉伸试验有限元模拟的本构模型。该模型预测实验宏观力-时间响应、真实应力-应变响应和有效应变率演化，具有良好的一致性。