高速列车设备舱底板夹芯结构异物冲击压痕行为及抗性强化

Impact indentation behavior and resistance enhancement of highspeed train equipment cabin bottom plate with honeycomb sandwich structure

采用理想刚-塑性模型结合芯材压剪屈服准则表征蜂窝夹芯结构压痕深度解析模型;利用有限元仿真分析面芯匹配系数(面板拉伸强度与芯材压剪强度的比值)对塑性压痕行为的影响;进而以局部抗性提升为目标,开展夹芯结构面芯几何参数优化设计,形成抗性强化设计原则。研究结果表明:引入芯材压剪屈服应力状态的压痕深度解析模型具有较高的预测精度;当芯材强度较低时,压痕深度随芯材强度变化更为敏感,当芯材强度较高时,压痕深度随面板强度变化更为敏感;与原有设备舱底板相比,优化后蜂窝夹芯设备舱底板侵彻深度下降10.10%,比吸能提升6.47%;采用合理的面芯匹配可获得更高的压痕抗性和比吸能。

The ideal rigid-plastic model combined with the compression and shear yield criterion of honeycomb core was used to characterize the analytic model of the indentation depth of the sandwich structure.The effect of the face sheet-core matching coefficient(the ratio of the tensile strength of the face sheet and the compressive shear strength of the honeycomb core)on the plastic indentation behavior was analyzed by finite element simulation.Furthermore,with the goal of local resistance improvement,the optimization design of the geometric parameters of the sandwich structure was carried out,and the resistance strengthening design principle was formed.The results show that the indentation depth analytical model with the core compression and shear yield stress state has high prediction accuracy.When the strength of the honeycomb core is low,the depth of the indentation is more sensitive to changes in the strength of the core material,and when the strength of the core material is high,the depth of the indentation is more sensitive to changes in the strength of the panel.Compared with the original structure,the penetration depth of the optimized honeycomb sandwich is reduced by 10.10%,and the specific energy absorption is increased by 6.47%.Using reasonable face sheet-core matching can obtain higher indentation resistance and specific energy absorption.