5083铝合金宽应变率实验与基于损伤的本构模型研究

发布时间：2018-11-22 16:20

【摘要】：5083铝合金材料在工程领域应用广泛,会受到包括冲击和碰撞等多种不同情况的强动加载,亟需对其宽应变率加载下的力学性能及其本构模型开展研究。首先,对5083铝合金进行了系统的准静态实验及中、高应变率加载下的拉伸和压缩实验,得到了宽应变率加载下的应力-应变曲线。实验结果表明,该材料在同一实验条件下所得到的应力-应变曲线,其强化阶段的拉伸曲线总是低于压缩曲线,并从微观机制上对这一现象进行了合理解释。然后,通过引入损伤,考虑了损伤对该材料拉伸加载情况下的力学性能影响。基于连续介质力学及其实验结果,获得了损伤演化方程。最后,借助改进的Johnson-Cook(JC)本构模型,并基于已确定的损伤演化方程,得到了考虑损伤的5083铝合金本构模型。通过实验曲线与所得模型曲线的对比,吻合良好,表明该模拟具有很好的适用性,能够对该材料的工程应用提供有效的科学依据、分析模型和必要的参考。
[Abstract]:5083 aluminum alloy material is widely used in engineering field and will be subjected to various kinds of strong dynamic loading including impact and impact. It is urgent to study the mechanical properties and constitutive model of 5083 aluminum alloy under wide strain rate loading. Firstly, the quasi-static experiments and the tensile and compression tests of 5083 aluminum alloy under medium and high strain rate loading are carried out, and the stress-strain curves under wide strain rate loading are obtained. The experimental results show that the stress-strain curves obtained under the same experimental conditions are always lower than the compression curves at the strengthening stage, and this phenomenon is explained reasonably from the microscopic mechanism. Then, the effect of damage on the mechanical properties of the material under tensile loading was considered by introducing damage. Based on the continuum mechanics and its experimental results, the damage evolution equation is obtained. Finally, based on the improved Johnson-Cook (JC) constitutive model and the established damage evolution equation, the 5083 aluminum alloy constitutive model considering damage is obtained. The comparison between the experimental curves and the obtained model curves shows that the simulation has good applicability and can provide an effective scientific basis for the engineering application of the material, and analyze the model and necessary reference.
【作者单位】：西南交通大学力学与工程学院;
【基金】：国家自然科学基金(11172251) 四川省青年科技创新团队(2013TD0004)
【分类号】：TG146.21

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