一种弹芯用聚碳酸酯的动态力学性能研究及本构关系

为了研究一种弹芯用聚碳酸酯材料在冲击作用下的动态力学响应,利用材料试验机和SHPB装置对该材料在不同应变率条件下动静态压缩性能进行测试分析,获得了该聚碳酸酯材料不同应变率下的应力应变曲线,试验结果表明:聚碳酸酯材料的压缩过程呈现明显的黏弹性现象,其动静态屈服强度和模量随着应变率的增加而变大,塑性阶段表现为应变软化与应变硬化相互作用的结果,且不同应变率下塑性阶段的应力应变曲线切向模量近似相等;基于试验结果建立了描述聚碳酸酯材料大变形力学行为的黏弹塑性本构模型,并得到了该材料的本构方程。对比分析显示,该模型可以较准确地描述聚碳酸酯材料动静态压缩行为。

Dynamic state performance and constitutive relation of polycarbonate for bullet cores

In order to study dynamic response of polycarbonate material for bullet cores under impact,static and dynamic state compressive performances of the material under different strain rates were tested and analyzed with a material testing machine and SHPB device to obtain stress-strain curves of polycarbonate under different stain rates.The test results showed that the compression process of polycarbonate material reveals obvious viscoelastic phenomenon;with increase in strain rate,its static and dynamic state yield strengths and elastic moduli increase;its plastic stage is the result of interaction between strain softening and strain hardening,and its plastic stress-strain curves’ tangential moduli under different strain rates approximately equal.Based on the test results,a visco-elastoplastic constitutive model describing polycarbonate material’s large deformation mechanical behavior was established,and this material’s constitutive equations were obtained.The contrastive analysis showed that the model can more correctly describe dynamic and static state compression behaviors of polycarbonate material.