星型-三角形负泊松比结构的面内压缩刚度可调控特性  

In-plane compression tunable stiffness characteristics of star-triangularhoneycomb with negative Poisson’s ratio

作　　者：魏路路 许世维 朱国华 赵轩 WEI Lulu;XU Shiwei;ZHU Guohua;ZHAO Xuan(School of Mechanical and Electrical Engineering,Xi’an University of Architecture and Technology,Xi’an 710055,China;Key Laboratory for Automotive Transportation Safety Enhancement Technology of the Ministry of Communication,PRC,Chang’an University,Xi’an 710064,China)

机构地区：[1]西安建筑科技大学机电工程学院,西安710055 [2]长安大学汽车运输安全保障技术交通行业重点实验室,西安710064

出　　处：《振动与冲击》2024年第4期105-114,共10页Journal of Vibration and Shock

基　　金：国家重点研发计划(2021YFB2501705);国家自然科学基金(52172361;52002309);汽车运输安全保障技术交通行业重点实验室(长安大学)开放基金资助(300102223504);陕西省自然科学基础研究计划(2020JQ-669)。

摘　　要：通过准静态面内压缩试验揭示星型-三角形结构(star-triangular honeycomb, STH)的刚度可调控特性。利用有限元模拟的方法研究非均匀壁厚STH的面内压缩刚度可调控机制,分析不同类型胞壁厚度比(t_(1)=t_(3))/t_(2)及胞壁角对其面内压缩刚度的影响。结果表明,STH在面内压缩载荷下呈2个线弹性阶段,且强化刚度比初始刚度显著增大。适当地增大内凹胞壁和垂直胞壁的厚度可同时提高STH的初始刚度及强化刚度;当(t_(1)=t_(3))/t_(2)>1.575后,初始刚度仍持续增大,而强化刚度反而逐渐减小,最终不再具有强化刚度阶段。胞壁角α≤30°时,增大胞壁角可提高STH的初始刚度及强化刚度,反之,初始刚度及强化刚度对应的应变随胞壁角的增大逐渐增大,而强化刚度逐渐减小并趋于消失。该研究将为可调节刚度负泊松比结构的设计提供新的思路。Quasi-static in-plane compression tests were used to reveal the tunable stiffness characteristics of star-triangular honeycomb(STH).The tunable mechanism of compression stiffness for STH with non-homogeneous cell-wall thickness was investigated via finite element simulation,and the influences of different cell-wall thickness ratios(t 1=t 3)/t 2 and cell-wall angles on the in-plane compression stiffness were analyzed.Results show that the stressstrain curve of STH shows two linear elastic stages under in-plane compression loading,and the strengthening stiffness is significantly higher than the initial stiffness.Appropriately increasing the thickness of re-entrant and vertical cell-walls can significantly improve the initial stiffness and strengthening stiffness of STH.When(t_(1)=t_(3))/t_(2)>1.575,the initial stiffness continues to increase while the strengthening stiffness gradually decreases,and finally the strengthening stiffness phase disappears.Whenα≤30°,increasing the cell-wall angle can improve the initial stiffness and strengthening stiffness of STH.On the contrary,the initial stiffness and strain corresponding to strengthening stiffness gradually increased with cell-wall angle,while strengthening stiffness gradually decreased and tended to disappear.This study is expected to provide a novel path for design of auxetic honeycombs with tunable stiffness.

关 键 词：星型-三角形结构(STH) 负泊松比 可调控刚度 非均匀壁厚 准静态压缩 

分 类 号：O347[理学—固体力学]