Three-Dimensional Dynamic Explicit Finite Element Analysis of Charpy Impact Test
Three-Dimensional Dynamic Explicit Finite Element Analysis of Charpy Impact Test
复制标题
简支梁冲击试验三维动态显式有限元分析
DOI：
10.4028/www.scientific.net/msf.879.1905
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发表时间：
2016
期刊：
影响因子：
--
通讯作者：
F. Minami
中科院分区：
文献类型：
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作者：
Yasuhito Takashima;T. Handa;F. Minami
采用动力显式有限元法分析了冲击试验中的惯性效应对冲击试样V形缺口前应力场的影响。采用三维有限元分析方法，考虑冲击器和压砧与试样的接触，对Charpy试样的变形行为和V型缺口附近塑性区的应力场进行了数值模拟。动态分析中考虑了应变速率对流动应力的影响以及冲击加载过程中温度的升高。分析表明，冲击载荷具有振荡性，冲击载荷的振荡受试件与撞针之间的接触刚度的影响。通过与使用仪器化夏比冲击试验机获得的实验结果进行比较，该试验机测量冲击载荷和载荷点位移，验证了分析。记录了载荷-时间曲线的振荡。通过有限元分析得到的峰值惯性载荷的大小和周期与实验结果基本一致。试样与撞针的接触刚度影响试样中V型缺口附近的应力场。这表明，夏比试件中的应力场应采用基于赫兹接触理论的考虑接触刚度的动态分析程序进行分析。
Dynamic explicit finite element (FE) analysis of the Charpy impact test was conducted in this study to investigate the inertial effect on the stress field ahead of the V-notch in a Charpy specimen. The deformation behavior of the Charpy specimen and the constraint effect on the stress field in the plastic zone near the V-notch were numerically simulated using three-dimensional FE analysis, while considering the contact of the specimen with the striker and anvil. The effect of the strain rate on the flow stress and the increase in temperature during impact loading were included in the dynamic analysis. This analysis shows that the impact load exhibits oscillation and the contact stiffness between the specimen and the striker affects the oscillation of the impact load. The analysis was validated by comparison with experimental results obtained using an instrumented Charpy impact testing machine, which measured the impact load and the load point displacement. The oscillation of the load–time curve was recorded. The magnitude and period of the peak inertia load obtained by the FE analysis were almost consistent with the experimental results. The contact stiffness between the specimen and the striker affected the stress field near the V-notch in the specimen. This indicates that the stress field in the Charpy specimen should be analyzed by the dynamic analysis procedure considering the contact stiffness based on the Hertzian contact theory.