纯钛高应变率拉伸力学行为的实验研究

摘要

利用MTS809材料试验机和旋转盘式间接杆杆型冲击拉伸实验装置,对多品纯钛进行了室温环境下应变率为0.001,0.01s-1的准静态和300,1400s-1的动态拉伸实验,获得了纯钛等温和绝热拉伸应力-应变曲线；实施了应变率为300s-1的冲击拉伸复元实验,获得了纯钛在高应变率下的等温应力-应变曲线.结果表明:纯钛的拉伸力学行为具有明显的应变硬化效应、应变率强化效应和绝热温升软化效应.采用修正的KHL模型较好地表征了纯钛在准静态和动态实验应变率范围内的拉伸力学行为.%Quasi-static and dynamic tension tests for pure titanium were performed using MTS809 testing system and rotating disk bar-bar tensile impact apparatus, respectively. The isothermal tension stress-strain curves at 0. 001s-1 and 0. 01s-1 and adiabatic tension stress-strain curves at 300s-1 and 1400s-1 were obtained. The dynamic tensile recovery test was carried out at the rate of 300s-1 and the isothermal stress-strain curve at the high strain rate was obtained. The results indicate that there exists the strain hardening, strain-rate strengthening and adiabatic temperature-rise softening phenomenon in the tesion behavior of pure titanium. A modified KHL model can describe and characterize the tensile behavior of titanium at different strain rates including high strain rates. The simulated results agree well with the experimental data.