热轧TB2钛合金织构多晶板动态压缩性能的各向异性

Anisotropy of Dynamic Compressive Properties of Textured Polycrystal Sheet of

摘要:

利用Instron 电子拉伸机和分离式霍普金生压杠(SHPB)实验装置, 研究了准静态和动态压缩条件下热轧TB2钛合金织构多晶板的力学性能。对TB2钛合金板材的轧向、横向以及轧制平面内与轧向成45°等3个方向进行了压缩实验, 得到了不同应变速率下的应力-应变曲线。结果表明：热轧TB2钛合金板材不同方向上的流变应力均随应变速率的增加而增加, 表现出明显的应变速率强化效应。准静态和动态力学性能均表现出各向异性, 且准静态和动态压缩行为规律不一致。考虑准静态和动态变形时可能的塑性变形机制, 基于微观晶体塑性变形理论, 定性讨论了热轧织构多晶TB2钛合金板屈服强度的各向异性

Abstract:

The quasistatic and dynamic compressive mechanical properties of textured polycrystal sheet of hot rolled TB2-titanium alloy were investigated by Instron apparatus and Split-Hopkinson pressure bar (SHPB) technology, respectively. Cylindrical specimens of textured titanium alloy sheet, which were cut with the cylinder axis along the rolling direction (RD), transverse direction (TD) and 45o direction (RD-45o) from the rolling direction lying in the rolling plane, were compressed at strain rates in the range of 10-3 to 103 s-1. The compressive stress-strain curves show that the flow stresses for different directions of hot rolled TB2-titanium alloy sheet increase with increase of the strain rate and the obvious effect of strain rate hardening is observed. Both the quasistatic and dynamical compressive mechanical properties exhibit anisotropy. Furthermore, the behavior for quasistatic compression is different from that for dynamical compression. Taking into account of possible mechanisms for quasistatic and dynamic plastic deformation, the mechanical anisotropy of textured polycrystal titanium alloy sheets was discussed based on the microscope crystal plasticity deformation theory