An extensive experimental campaign was run to investigate the influence of the loading direction, stress state (triaxiality ratio ranging from −0.5 to 1), and strain rate (from 10⁻³ to 1.5x10³s⁻¹) on the ductile fracture of Ti-6Al-4V titanium alloy. Microscopic and macroscopic observations provided some insight into the shear-driven or micro-voiding-controlled damage mechanisms prevailing at low and high triaxiality ratios, respectively. Numerical simulations were run to determine the local loading paths to fracture in terms of plastic strain as a function of stress triaxiality ratio and Lode parameter. The ductility was found to be anisotropic, but only weakly dependent on the strain rate in the considered range. The anisotropy in ductility was different in tension (maximum along DD) and in compression (maximum along ND). The fracture strain decreased with the absolute value of the triaxiality, with a maximum close to zero. No clear correlation with the Lode parameter was found.

进行了广泛的实验活动以研究加载方向、应力状态（三轴度比范围从 -0.5 到 1）和应变率（从 10 ^-3到 1.5x10 ³ s ^-1) 对 Ti-6Al-4V 钛合金延性断裂的影响。微观和宏观观察提供了对分别在低三轴率和高三轴率下普遍存在的剪切驱动或微空隙控制的损伤机制的一些见解。运行数值模拟以根据作为应力三轴度比和 Lode 参数的函数的塑性应变来确定断裂的局部加载路径。发现延展性是各向异性的，但仅微弱地依赖于所考虑范围内的应变率。延展性的各向异性在拉伸（沿 DD 方向最大）和压缩（沿 ND 方向最大）方面是不同的。断裂应变随三轴度的绝对值而减小，最大值接近于零。未发现与 Lode 参数的明确相关性。