【摘要】 通过系列准静态与动态力学实验得到了铝锂合金材料的基本力学参数。证实了该种材料具有独特的应变率软化特性 ,并揭示了材料应变率软化效应的极限性特征 ,提出了极限应变率软化材料的概念 ,从而对突加载荷下粘塑性材料中也会出现双波结构的现象给出了合理的解释。为便于实际应用 ,还对实验得到的材料应力 应变曲线进行了拟合 ,提出了一种便于实际应用的材料本构关系的具体形式 ,即双幂次应变硬化 极限幂次应变率软化本构关系。更多还原

【Abstract】 In this paper, with the series of quasi static and dynamic experiments of mechanics, the basic mechanical parameters of the Al/Li alloy have been obtained. By comparison of the experimental results of different strain rates, it is shown that the Al/Li alloy has the extraordinary property of strain rate softening. Also the limit characteristics of the strain rate softening of the material are revealed, based on which the concept of limit strain rate softening material is proposed so that the existence of double wave phenomenon in viscoplastic material is reasonably explained. Furthermore, we have completed the fitting of the experimental strain stress curves, and presented one concrete form of the constitutive model of the material convenient for practical application, which is a constitutive relation of double powers strain hardening with a limit and power strain rate softening.更多还原