Zhang Kebin, Li Wenbin, Zheng Yu, Yao Wenjin, Zhao Changfang
ZNDY of Ministerial Key Laboratory, Nanjing University of Science and Technology, Nanjing 210094, China.
School of Mechanical Engineering, Nanjing University of Science and Technology, Nanjing 210094, China.
Polymers (Basel). 2020 Jul 14;12(7):1561. doi: 10.3390/polym12071561.
The temperature and strain rate significantly affect the ballistic performance of UHMWPE, but the deformation of UHMWPE under thermo-mechanical coupling has been rarely studied. To investigate the influences of the temperature and the strain rate on the mechanical properties of UHMWPE, a Split Hopkinson Pressure Bar (SHPB) apparatus was used to conduct uniaxial compression experiments on UHMWPE. The stress-strain curves of UHMWPE were obtained at temperatures of 20-100 °C and strain rates of 1300-4300 s. Based on the experimental results, the UHMWPE belongs to viscoelastic-plastic material, and a hardening effect occurs once UHMWPE enters the plastic zone. By comparing the stress-strain curves at different temperatures and strain rates, it was found that UHMWPE exhibits strain rate strengthening and temperature softening effects. By modifying the Sherwood-Frost model, a constitutive model was established to describe the dynamic mechanical properties of UHMWPE at different temperatures. The results calculated using the constitutive model were in good agreement with the experimental data. This study provides a reference for the design of UHMWPE as a ballistic-resistant material.
温度和应变率对超高分子量聚乙烯（UHMWPE）的弹道性能有显著影响，但超高分子量聚乙烯在热机械耦合作用下的变形情况鲜有研究。为了研究温度和应变率对超高分子量聚乙烯力学性能的影响，采用分离式霍普金森压杆（SHPB）装置对超高分子量聚乙烯进行单轴压缩实验。在20 - 100°C的温度和1300 - 4300 s⁻¹的应变率下获得了超高分子量聚乙烯的应力 - 应变曲线。基于实验结果，超高分子量聚乙烯属于粘弹塑性材料，一旦进入塑性区就会出现硬化效应。通过比较不同温度和应变率下的应力 - 应变曲线，发现超高分子量聚乙烯呈现出应变率强化和温度软化效应。通过修正舍伍德 - 弗罗斯特模型，建立了一个本构模型来描述超高分子量聚乙烯在不同温度下的动态力学性能。使用该本构模型计算得到的结果与实验数据吻合良好。本研究为超高分子量聚乙烯作为防弹材料的设计提供了参考。
