酚醛层压材料的冲击力学行为及本构模型

为了研究酚醛层压材料的冲击力学行为并获得本构模型，利用万能试验机和整形修正的分离式霍普金森压杆(SHPB)装置，对材料试样进行了应变率范围为10-3~103 s-1的单轴压缩实验，得到了不同加载应变率下的应力应变曲线，对其在准静态、动态载荷下的压缩破坏机理进行了初步探讨。结果表明，酚醛层压材料具有较强的应变率效应，与准静态(1.67×10-3 s-1)时相比，在动态载荷(7×102 s-1)下，峰值应力增加了约10倍；破坏应变减少了约一半；在准静态和动态加载条件下试样力学性能的差异是由于纤维基体界面特性以及不同应变率下破坏模式的不同；采用朱-王-唐本构方程描述了酚醛层压材料力学行为，拟合得到了本构方程的系数，在加载过程中，理论计算值与实验结果吻合较好。

Dynamic behavior and constitutive model of phenolic cotton fabric material under impact loading

In order to obtain mechanical properties of phenolic cotton fabric material at different strain rates, we performed experiments of the uniaxial compression tests of phenolic cotton fabric material at the strain rate ranging from 10-3 to 103 s-1, using the universal testing machine and the split Hopkinson pressure bar (SHPB), obtained the stress-strain curve at different strain rates, and discussed compression failure mechanism under quasi-static and dynamic loads. The results from our experiments show that the dynamic compression fail strength of phenolic cotton fabric material has strong strain rate sensitivity and it increases along with the strain rate. Compared with the stress under the quasi-static loading, the peak stress under the dynamic loading increases by approximately 10 times, while the failure strain is reduced to about half. The differences in the mechanical properties under quasi-static and dynamic loading conditions is due to the strain rate effect of the fiber matrix interface characteristics on the one hand, and to the differences in failure modes at different strain rates on the other. Zhu-Wang-Tang (ZWT) constitutive was adopted to describe the mechanical behavior of the phenolic cotton fabric material.