复合材料层板动态力学性能和本构关系研究

在不同温度环境下 ,利用MTS材料试验机 ,在中等应变速率 ( 1 /s)下 ,对玻璃布———环氧层板的动态力学性能进行了实验研究 ,给出一种较为可靠的复合材料拉伸试样设计方法 ,获得了杨氏模量、拉伸强度和泊松比等力学参数。实验结果表明 ,玻璃布———环氧层板具有明显的应变率相关和温度效应。采用Johnson提出的温度、应变率相关的本构模型 ,根据实验数据拟合了玻璃布———环氧层板材料的本构关系 ,分析表明该本构关系可以很好地描述材料的应变率和温度效应。

Study of constitutive mode and dynamic mechanical properties of composites at different temperatures

Impact tensile experiments of glass_cloth/epoxy laminates under different temperatures are carried out, the curves of stress_strain are measured, and the Young's modulus, tensile strength and Poisson's ratio of the laminates are obtained. A study of failure process for the laminates under different conditions is also conducted. The experiment results show that the dynamic response of the laminates is clearly dependent upon temperatures and strain rates and there exists dynamic toughness in the laminates. A design method of tensile sample of composite laminates is reported. According to the experimental results, a constitutive equation of glass_cloth/epoxy laminates is developed, and with which strain rate dependence and thermo_softening effect of the laminates can be described clearly.