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Applied Mathematics and Mechanics(English Edition) 2023年第4期44卷 525-546页

作者： Yanpeng YUE yongping wan School of Aerospace Engineering and Applied Mechanics Tongji UniversityShanghai 200092China

The closed-form solutions of the dynamic problem of heterogeneous piezoelectric materials are formulated by introducing polarizations into a reference medium and using the generalized reciprocity *** solutions can be reduced to the ones of an elastodynamic *** on the effective medium method,these closedform solutions can be used to establish the self-consistent equations about the frequencydependent effective parameters,which can be numerically solved by *** predictions are compared with the experimental results,and good agreement can be ***,the analyses on the effects of microstructure and wavelength on the effective properties,resonance frequencies,and attenuation are also presented,which may provide some guidance for the microstructure design and analysis of piezoelectric composites.

关键词： piezoelectric composite dynamic effective property self-consistent method resonance frequency wavelength

Effective properties of coated fibrous piezoelectric composites with spring-type interfaces under anti-plane mechanical and in-plane electrical loads

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Science China(Physics,Mechanics & Astronomy) 2016年第10期59卷 58-65页

作者： Yin Shi yongping wan Zheng Zhong School of Aerospace Engineering and Applied Mechanics Tongji University

In this paper,we investigate the effective properties of three-phase(matrix/coating/fiber)cylindrical piezoelectric composites with imperfect interfaces under anti-plane mechanical and in-plane electrical *** using the electromechanically coupling spring-type interface model and the generalized self-consistent method(GSM),we analytically derived the effective electroelastic *** present solutions include as special cases the three-phase cylindrical piezoelectric composites with perfect interfaces as well as the two-phase(matrix/fiber)case with imperfect or perfect *** calculations are graphically shown to demonstrate dependence of the effective moduli on the interfacial *** particular size-dependent characteristic due to the interfacial imperfection is also discussed.

关键词： effective moduli piezoelectric composites spring-type interface generalized self-consistent method size effect

THE EFFECTIVE ELECTROMECHANICAL PROPERTIES OF CELLULAR PIEZOELECTRET FILM:FINITE ELEMENT MODELING

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Acta Mechanica Solida Sinica 2013年第1期26卷 1-8页

作者： yongping wan Liangliang Fan Zheng Zhong School of Aerospace Engineering and Applied Mechanics Tongji University

Cellular space-charge polymer film, also called cellular piezoelectret, has very large piezoelectric effect due to their unique microvoid structure. In this article, the cellular piezoelectret film is considered to be a periodic composite material with closed-cell microvoids aligned periodically. Three dimensional finite element modeling is carried out to obtain the effective elastic modulus and piezoelectric coefficients. Sensitivity analysis was presented by modeling the effec- tive electromechanical properties with different individual variable, including material constants and void shape parameters. By assuming a relation between void shape and void volume fraction, the finite element model can simulate quite well the inflation experiments of the voided charged Polypropylene film published in literature. Finally, the finite element model is used to explore the voided charge polymer film with non-uniform distribution of the trapped charges on the internal surface of voids. It was found that the resultant overall piezoelectric coefficients will be more significant if charges are closely gathered in the central area, and sparse in the around area of the internal surface of voids.

关键词： piezoelectret electromechanical finite element methods

Variational bounds of the effective moduli of piezoelectric composites

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Science China(Physics,Mechanics & Astronomy) 2012年第11期55卷 2106-2113页

作者： wan yongping XIE LongTao ZHONG Zheng School of Aerospace Engineering and Applied Mechanics Tongji UniversityShanghai 200092China

The classical Hashin-Shtrikman variational principle was re-generalized to the heterogeneous piezoelectric *** auxiliary problem is very much simplified by selecting the reference medium as a linearly isotropic elastic *** electromechanical fields in the inhomogeneous piezoelectrics are simulated by introducing into the homogeneous reference medium certain eigenstresses and eigen electric fields.A closed-form solution can be obtained for the disturbance fields,which is convenient for the manipulation of the energy *** an application,a two-phase piezoelectric composite with nonpiezoelectric matrix is *** of upper and lower bounds for the overall electromechanical moduli of the composite can be *** bounds are shown better than the Voigt-Reuss type ones.

关键词： variational bound piezoelectric composite effective modulus

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含不完美界面的磁电复合材料倾斜裂纹问题

复合材料学报 2018年第12期35卷 3474-3486页

作者：刘宝汉万永平同济大学航空航天与力学学院上海200092

研究了含非完美界面的双层压电/压磁复合材料中压电相存在一个倾斜于界面的III型裂纹问题。采用弹簧型耦合界面模型模拟非完美界面,运用Fourier积分变换法将裂纹面条件转化为奇异积分方程,并使用Lobatto-Chebyshev方法数值求解了裂纹尖... 详细信息

研究了含非完美界面的双层压电/压磁复合材料中压电相存在一个倾斜于界面的III型裂纹问题。采用弹簧型耦合界面模型模拟非完美界面,运用Fourier积分变换法将裂纹面条件转化为奇异积分方程,并使用Lobatto-Chebyshev方法数值求解了裂纹尖端应力强度因子(SIF)。详细地研究了裂纹尖端SIF与界面参数、压电/压磁材料参数和材料的层厚、裂纹的倾斜角、裂纹与界面的距离等几何参数的关系。结果表明:力学不完美性可以独立地增大SIF,而磁学、电学不完美性只有与力学不完美性耦合时才会减小SIF;力学-电学、力学-磁学不完美性的耦合会减小SIF,而磁学-电学不完美性的耦合不会影响SIF;磁场作用下,增大压磁层弹性模量会减小SIF,而增大压电层压电系数,减小压电层弹性模量和介电常数,均会减小SIF;界面不完美性会影响SIF随裂纹倾斜角度或裂纹与界面之间距离的变化规律;在一定范围内增加压电层或压磁层厚度可以减小SIF。

关键词：磁电复合材料非完美界面 Ⅲ型倾斜裂纹 Fourier积分变换奇异积分方程应力强度因子

磁性形状记忆合金力磁耦合行为的唯象模型研究

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固体力学学报 2016年第2期37卷 135-144页

作者：龚臣成万永平同济大学航空航天与力学学院上海200092

论文基于热力学及耗散概念,推导了一种磁性形状记忆合金(MSMA)的力磁耦合三维唯象本构关系.采用内变量模拟微观相结构及磁结构的演化,考虑了马氏体相变过程及马氏体重定向过程.同时,论文摒弃了传统的单畴假设,运用双畴模型来模拟循环加... 详细信息

论文基于热力学及耗散概念,推导了一种磁性形状记忆合金(MSMA)的力磁耦合三维唯象本构关系.采用内变量模拟微观相结构及磁结构的演化,考虑了马氏体相变过程及马氏体重定向过程.同时,论文摒弃了传统的单畴假设,运用双畴模型来模拟循环加载下的磁畴结构演化.根据文献中的二维加载情况的实验数据确定本模型的参数.数值模拟结果表明:论文的模型可以很好的捕捉磁性形状记忆合金的形状记忆效应、应变及磁化响应的滞后性.应变及磁化响应模拟结果明显比文献中的理论模型更加吻合实验数据,低磁场时尤为明显.

关键词：磁性形状记忆合金马氏体变体重定向磁场诱导相变唯象模型

含非完整界面的功能梯度压电材料Ⅲ型裂纹问题

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力学季刊 2019年第4期40卷 740-752页

作者：李冉万永平同济大学航空航天与力学学院

本文研究了含非完整界面的功能梯度压电复合材料的Ⅲ型裂纹问题.此裂纹垂直于非完整界面,采用弹簧型力电耦合界面模型模拟非完整界面.界面两侧材料的性质,如弹性模量、压电常数和介电常数均假定呈指数函数形式且沿着裂纹方向变化.运用... 详细信息

本文研究了含非完整界面的功能梯度压电复合材料的Ⅲ型裂纹问题.此裂纹垂直于非完整界面,采用弹簧型力电耦合界面模型模拟非完整界面.界面两侧材料的性质,如弹性模量、压电常数和介电常数均假定呈指数函数形式且沿着裂纹方向变化.运用积分变换法将裂纹面条件转换为奇异积分方程,并使用Gauss-Chebyshev方法对其进行数值求解.根据算例结果讨论了一些退化问题并分析了裂纹尖端强度因子与材料的非均匀系数和非完整界面参数的关系.

关键词：压电功能梯度复合材料非完整界面积分变换奇异积分方程应力强度因子

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基于机器学习的人体外鼻部材料参数识别方法

力学季刊 2022年第4期43卷 824-834页

作者：蔡镇万永平张辉同济大学航空航天与力学学院上海200092 希美得医疗美容医院陕西西安710000

隆鼻术是一种通过手术植入隆鼻假体来改善鼻部外观形态的鼻整形术式.长期以来隆鼻手术假体尺寸的确定完全依赖于医生的术前经验判断及术中手工雕刻.术中植入假体尺寸不合适,可能会在术后导致各种并发症.本文将人体的外鼻部作为一种超弹... 详细信息

隆鼻术是一种通过手术植入隆鼻假体来改善鼻部外观形态的鼻整形术式.长期以来隆鼻手术假体尺寸的确定完全依赖于医生的术前经验判断及术中手工雕刻.术中植入假体尺寸不合适,可能会在术后导致各种并发症.本文将人体的外鼻部作为一种超弹性材料来考虑,对受术者的鼻部皮肤软组织进行拉伸试验,使用人工神经网络来确定材料参数与拉伸试验数据之间的关系,提出了一种基于神经网络的外鼻部材料参数识别方法.本文成果有助于医生及假体设计生产厂家定量了解受术者鼻部皮肤状况和鼻部软组织拉伸的安全范围,进而确定隆鼻术假体尺寸,提高手术成功率,减少术后并发症.

关键词：隆鼻术鼻部张力测试机器学习人工神经网络参数识别

An analytical nonlinear model for laminate multiferroic composites reproducing the dc-magnetic-bias dependent magnetoelectric properties

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An analytical nonlinear model for laminate multiferroic comp...

北京力学会第18届学术年会

作者： Lizhi Lin yongping wan Faxin Li ( State Key Laboratory for Turbulence and Complex Systems, College of Engineering, Peking University, 100871 )

In this paper, we proposed an analytical nonlinear model for laminate multiferroic composites. Analysis of this model on L-T and L-L mode of sandwiched Terfenol-D/PZT/Terfenol-D composites well reproduces the observed... 详细信息

关键词： Laminated multiferroic composites Nonlinear ME model Stress attenuation ME coefficient

来源： cnki会议评论

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含力磁屈服区的压磁材料硬币型裂纹问题研究

力学季刊 2021年第3期42卷 538-549页

作者：李梦涵吴琼万永平同济大学航空航天与力学学院上海200092

本文利用Hankel变换及Copson求解方法,得到了在无穷远处磁荷载以及对称力荷载作用下的无限大压磁材料中,硬币型裂纹在裂纹尖端含有环状力磁双屈服区情况下的相关解析解.本文考虑了磁屈服区尺寸小于、大于、等于力屈服区尺寸的三种情况.... 详细信息

本文利用Hankel变换及Copson求解方法,得到了在无穷远处磁荷载以及对称力荷载作用下的无限大压磁材料中,硬币型裂纹在裂纹尖端含有环状力磁双屈服区情况下的相关解析解.本文考虑了磁屈服区尺寸小于、大于、等于力屈服区尺寸的三种情况.结果表明:屈服区尺寸不仅与外荷载及材料常数相关,更与力磁屈服区尺寸的相对大小有关;其中,较大尺寸的屈服区仅受同性质单一荷载影响,与材料常数无关;而较小尺寸屈服区受力磁两荷载与材料常数共同影响;裂纹张开位移、磁势跳变均沿裂纹面径向增大而减小;裂尖张开位移、裂尖磁势跳变与材料常数相关,且随外荷载增大而增大.

关键词： Hankel变换 Copson方法压磁材料硬币型裂纹力磁屈服区