为了解应变率对聚碳酸酯拉伸力学行为的影响,在旋转盘式间接杆杆型冲击拉伸试验机和MTS809材料试验机上,对聚碳酸酯棒材进行了高应变率和准静态加载下的单向拉伸试验,应变率分别为380s^-1、800s^-1、1750s^-1和0.001s^-1、0.05s^-1,得到了聚碳酸酯的拉伸应力应变曲线。试验结果表明:聚碳酸酯的拉伸力学性能具有明显的应变率相关性,其屈服应力和失稳应变随应变率的增加而增大。依据试验结果,采用朱王唐粘弹性本构模型来描述聚碳酸酯的非线性粘弹性拉伸力学行为。模型结果显示,在本文实施的应变率范围内,朱王唐模型可以较好地表征聚碳酸酯的拉伸应力应变响应。
To understand the strain rate effect on the tensile behavior of polycarbonate bar, high strain-rate and quasi-static loading unilateral tension tests were carried out using rotating disc bar-bar tensile impact apparatus and MTS809 material testing system. Engineering stress -engineering strain curves were obtained at strain rates of 380, 800, 1750, 0.001 and 0.05 s^-1 respectively. Experimental results show that the effect of strain rate on tensile properties of polycarbonate is apparent. The values of yield stress and unstable strain increases with strain rate increasing. The ZWT constitutive model was used to describe the nonlinear tensile behavior of polycarbonate bar subjected to quasi-static and high rate loading. Comparison between the model results and the experimental data indicates that the ZWT model can well characterize the stress-strain responses of polycarbonate within the rate range investigated in present paper.