考虑应变率效应的轻量化座钣有限元分析

Finite Element Analysis of Lightweight Base Plate Considering Strain Rate Effect

室温条件下,采用Instron实验机和分离式Hopkinson压杆(SHPB)实验装置对TC4钛合金进行压缩实验,得到了不同应变率下的真应力-真应变曲线。通过对应力-应变曲线拟合分析,建立了TC4钛合金的Johnson-Cook(JC)本构模型。基于该本构模型,采用ABAQUS/Explicit对TC4钛合金高应变率下的冲击压缩实验进行了数值模拟,通过实验结果与仿真数据的对比分析,验证了该本构模型参数的合理性。为实现迫击炮轻量化的目标,设计了一种新型轻量化TC4钛合金质迫击炮座钣。通过建立冲击载荷下迫击炮座钣的有限元模型,考虑材料的应变率效应,对座钣的强度和刚度进行了分析,得到了座钣的应力和位移的变化规律。

The compressive true stress-true strain curves of TC4 alloy with different strain rates at room temperature were obtained by the Instron test machine and split Hopkinson pressure bar(SHPB)device.Johnson-Cook(JC)constitutive model of TC4 alloy was established by fitting the experimentally obtained stress-strain curves.Based on the constitutive model,the impact compression experiment of TC4 alloy at high strain rate was simulated by ABAQUS/Explicit.The reasonability of the parameters for the constitutive model was verified by comparing the experimental results with the simulation data.Results show that the numerical results are in good agreement with the experimental results.In order to achieve the purpose of lightweight mortar,a new lightweight mortar base plate made of TC4 alloy was designed.The finite element model(FEM)of the base plate under impact loading was established considering the strain rate effect of TC4 alloy.The strength and stiffness of the base plate were analyzed,and the variation law of the stress and displacement of the base plate was obtained.The simulation results show that the stiffness and strength of the base plate meet operation requirements.