TC4钛合金板厚度对其撞击失效特性影响研究

为了揭示TC4钛合金板抗撞击性能与失效模式随厚度的变化规律及机理,采用ABAQUS/Explicit有限元软件建立平头弹撞击不同厚度靶板的模型,对弹体撞击不同厚度靶板进行计算。通过对比数值仿真与撞击实验结果,验证仿真模型的有效性。研究结果表明,靶板的主要失效模式、耗能机制、弹道极限随其厚度增加会发生改变,靶板厚度存在对应的转折值。对于TC4钛合金薄板,当靶板厚度比较小时,靶板拉伸撕裂破坏占主导作用。但是,当靶板厚度比较大时,靶板主要失效模式是局部剪切破坏。当靶板厚度小于4 mm、大于8 mm时,弹道极限速度随靶板厚度的增加而增加;当厚度为4~8 mm时,弹道极速度变化不明显。

Influence of the thickness on the impact failure characteristics of TC4 titanium alloy plate

In order to study the influence of thickness on the penetration resistance and failure mode of TC4 titanium alloy plate, the axial symmetry model of blunt projectile impacting plate with different thickness was established using ABAQUS/Explicit finite element software, and numerical simulation of the projectile impact plate with different thickness was carried out. The effectiveness of the simulation model was verified by comparing the results of numerical simulation and impact experiment. The results show that the main failure modes, energy dissipation mechanism and ballistic limit of plate change with the increase of thickness, and there is a critical value for the thickness of the target. For TC4 titanium alloy material, tensile tear failure plays a dominant role in the failure mode of thin plate. And the failure mode of thick plate is dominated by local shear failure. The ballistic limit velocity of plate increases with the increase of the thickness when less than 4 mm or more than 8 mm. When the thickness is between 4 mm and 8 mm, the velocity of ballistic limit basically remains unchanged.