星型拉胀蜂窝材料在压剪复合加载下的力学特性研究  

Mechanical properties of star-shaped auxetic honeycomb material under compression-shear composite loading

作　　者：罗耿 莫端钰 刘浚哲 柴成鹏 陈轶嵩 LUO Geng;MO Duanyu;LIU Junzhe;CHAI Chengpeng;CHEN Yisong(School of Automobile,Chang’an University,Xi’an 710064,China;State Key Lab of Advanced Design and Manufacturing for Vehicle Body,Hunan University,Changsha 410082,China)

机构地区：[1]长安大学汽车学院,西安710064 [2]湖南大学汽车车身先进设计制造国家重点实验室,长沙410082

出　　处：《振动与冲击》2023年第13期183-192,共10页Journal of Vibration and Shock

基　　金：陕西省自然科学基金项目(2021JQ-220);汽车车身先进设计制造国家重点实验室开放基金(32015006)。

摘　　要：拉胀蜂窝材料由于其良好的力学特性以及稳定的吸能特性,广泛地应用于各类防护结构。该文针对星型拉胀在压剪复合加载下的力学特性开展了研究工作。基于有限元技术建立星型拉胀蜂窝材料的数值模型,并基于增材制造技术和万能试验机开展验证试验,开展了星型拉胀蜂窝材料在不同压剪复合加载角度和速度下的仿真研究,对星型拉胀蜂窝材料在各个加载工况下的力学特性与变形模式开展研究,结果表明,星型拉胀蜂窝材料在准静态复合加载下依托胞元旋转发生整体变形,并产生倾斜变形带压溃,随着加载速度提升,由于惯性效应的增强,细观结构间的挤压变形更加充分,材料变形模式由整体变形向局部变形转变,形成冲击波。基于椭圆方程对星型拉胀蜂窝材料初始屈服应力进行拟合,建立星型拉胀蜂窝材料的准静态/动态屈服面,随着速度的提高,屈服面呈现出明显强化;最后通过对星型拉胀蜂窝材料的吸能特性研究表明,随着加载角度的增大,材料法向和切向总吸能分别呈现出下降和提高的趋势,且切向吸能特性对角度的改变相对法向方向更加敏感。Because of its good mechanical properties and stable energy absorption properties,auxetic honeycomb material is widely used in various protective structures.Here,mechanical properties of star-shapedauxetic honeycomb material under compression-shear composite loading were studied.Firstly,the numerical model of star-shapedauxetic honeycomb material was established based on the finite element method,verification tests were conducted based on additive material manufacturing technique and universal testing machine,and simulation study on mechanical properties and deformation modes ofstar-shaped auxetic honeycomb material under various loading conditions,such as,different compression-shear loading angles and speedswas performed.The results showed that under quasi-static composite loading,star-shaped auxetic honeycomb material undergoes overall deformation relying on cell rotation,and produces inclined deformation band collapse;with increase in loading speed,due to enhancement of inertial effect,extrusion deformation among micro-structures is more sufficient,and material deformation mode changes from overall deformation to local deformation to form shock waves;based on the elliptic equation,initial yield stress of star-shaped auxetic honeycomb material is fitted to establish quasi-static/dynamic yield surface of star-shaped auxetic honeycomb material;with increase in loading speed,yield surface has obvious strengthening.Finally,study on energy absorption property of star-shaped auxetic honeycomb material showedthat with increase in loading angle,normal and tangential total energy absorptions of the material have downward and upward trends,respectively;tangential energy absorption propertyis more sensitive to change of loading angle than normal energy absorption property be.

关 键 词：拉胀材料 星型蜂窝 复杂加载 屈服面 吸能特性 

分 类 号：TH212[机械工程—机械制造及自动化] TH213.3