具有挠曲电效应的薄膜-有限厚度基底结构的屈曲行为研究  

Research on Buckling Behavior in Thin-Film-and-Finite-Thickness-Substrate Structures Considering Flexoelectric Effects

作　　者：王辰宇 王博[1,2] 张博涵 黄永安 欧阳华江[4] Chenyu Wang;Bo Wang;Bohan Zhang;Yongan Huang;Huajiang Ouyang(Department of Engineering Mechanics,Northwestern Polytechnical University,Xi'an,710072;Research Development Institute of Northwestern Polytechnical University in Shenzhen,Shenzhen,518063;State Key Laboratory of Digital Manufacturing Equipment and Technology,Huazhong University of Science and Technology,Wuhan,430074;School of Mechanical Engineering,Southwest Jiaotong University,Chengdu,610031)

机构地区：[1]西北工业大学工程力学系,西安710072 [2]西北工业大学深圳研究院,深圳518063 [3]华中科技大学智能制造装备与技术全国重点实验室,武汉430074 [4]西南交通大学机械工程学院,成都610031

出　　处：《固体力学学报》2025年第1期15-26,共12页Chinese Journal of Solid Mechanics

基　　金：国家自然科学基金(12172282);广东省基金(2024A1515010767);中央高校基本科研业务费专项资金资助。

摘　　要：本文建立了一个具有挠曲电效应薄膜-有限厚基底结构屈曲的理论模型,通过最小能量法对结构总能量进行分析,研究了挠曲电效应对薄膜-基底结构发生屈曲演化的影响,并对全局屈曲和局部起皱两种屈曲模式进行了区分.目前研究表明薄膜中挠曲电效应越强,结构越细长,越倾向于发生全局屈曲.同时,结构发生失稳所需的临界应变越大,且挠曲电效应对局部起皱失稳模式的影响更突出.挠曲电效应的存在会增大结构的刚度,改善结构的可拉伸性.褶皱薄膜中挠曲电效应的可控性对材料极性的产生与控制有着重要意义.这些发现将有助于微纳尺度上机电设备的设计与应用.Large-area and tunable strain gradients arise from inhomogeneous deformation in wrinkled thin films,making them promising for flexoelectric applications.Consequently,the structure and buckling modes of these films have garnered significant attention.In this paper,an electromechanical coupling model is developed to study the buckling behavior of thin-film-and-finite-thickness-substrate structures with flexoelectric effects.First,the influence of flexoelectric effects on the buckling evolution of thin-film-substrate structures is assessed using the minimum energy method.Two buckling modes,i.e.,global buckling and local wrinkling,are distinguished by changing structural parameters and the flexoelectric coefficient.Results show that stronger flexoelectric effects lead to slenderer films and an increased likelihood of global buckling.Additionally,a stronger flexoelectric effect raises the critical strain required for buckling and significantly impacts local wrinkling mode.In local wrinkling,as the amplitude increases,the maximum strain in thin films decreases;sparser wrinkles with greater amplitude occur with a more pronounced flexoelectric effect.When the flexoelectric effect reaches a certain threshold,the buckling mode of the thin film shifts from local wrinkling to global buckling.The flexoelectric effect enhances structural stiffness and stretchability.Moreover,flexoelectric polarization can be continuously adjusted with compressive strain,highlighting its controllability in wrinkled thin films for generating and managing material polarity.These findings will aid in the design and application of micro and nanoscale electromechanical devices.

关 键 词：挠曲电效应 有限厚度基底 薄膜-基底结构 屈曲模式 

分 类 号：O484[理学—固体物理]