Mechanics of Materials最新文献_第5页

3D finite element investigation of hyperelastic foam behavior. I. Voronoi closed-cell microstructures 超弹性泡沫行为的三维有限元研究。1 . Voronoi闭细胞微结构

IF 4.1 3区材料科学 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY

Mechanics of Materials

Pub Date : 2025-12-04 DOI: 10.1016/j.mechmat.2025.105566

Thomas C. Merlette, Julie Diani

The mechanical behavior of isotropic, elastomeric, Classical Voronoi closed-cell foams is investigated numerically using 3D finite element simulations under finite-strain uniaxial compression, and infinitesimal-strain shear and hydrostatic loading conditions. Foam microstructures with porosities ranging from 77% to 95% and narrow pore volume distributions were generated by subtracting irregular polyhedra, obtained from Voronoi tessellations of well dispersed seed points, from a cubic matrix. Severe finite-strain uniaxial compression, up to 95% nominal strain, was simulated using the Abaqus/Explicit solver. Parametric studies revealed that the compressive response of the foams scales proportionally with the factor

{(1 - c)}^{2}

, where

c

denotes the porosity. Moreover, at high porosities (typically 90%), the influence of the base polymer’s hyperelasticity reduces to its initial shear modulus

μ_{0}

, since the matrix undergoes only limited strain, whereas the effect of the polymer’s large-strain behavior becomes significant at lower porosities (typically 77%). As a result, all stress–strain curves collapse onto a single master curve when the stress is normalized by

μ_{0} {(1 - c)}^{2}

. The effect of internal gas pressure within the closed cells was also assessed numerically and compared against experimental data, validating the simple analytical model proposed by Gibson and Ashby (1997). At small strains, the shear modulus is accurately predicted by the Differential Hollow Sphere Assemblage (DHSA) originally developed for spherical voids. However, the same model was found to overestimate the bulk modulus, and a phenomenological correction is therefore proposed to enable rapid and more accurate estimation of this quantity.

采用三维有限元模拟方法，对各向同性、弹性、经典Voronoi闭孔泡沫在有限应变单轴压缩、无穷小应变剪切和静水加载条件下的力学行为进行了数值模拟研究。通过从立方矩阵中减去分散良好的种子点的Voronoi镶嵌得到的不规则多面体，可以生成孔隙率为77%至95%的窄孔体积分布的泡沫微结构。使用Abaqus/Explicit求解器模拟了严重的有限应变单轴压缩，高达95%的标称应变。参数研究表明，泡沫的压缩响应与因子（1−c）2成比例，其中c表示孔隙率。此外，在高孔隙率（通常为90%）下，由于基体只承受有限应变，基底聚合物超弹性的影响降低到初始剪切模量μ0，而在低孔隙率（通常为77%）下，聚合物的大应变行为的影响变得显著。结果表明，当应力被μ0(1−c)2归一化时，所有应力-应变曲线都坍塌成一条主曲线。封闭细胞内内部气体压力的影响也进行了数值评估，并与实验数据进行了比较，验证了Gibson和Ashby（1997）提出的简单分析模型。在小应变下，剪切模量可以通过最初为球形空洞开发的微分空心球组合（DHSA）准确预测。然而，同样的模型被发现高估了体积模量，因此提出了一种现象学校正，以便能够快速和更准确地估计这个量。

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引用次数: 0

Discrete element simulations of granular sea ice in triaxial tests under different confining pressures and boundary conditions 不同围压和边界条件下颗粒海冰三轴试验离散元模拟

IF 4.1 3区材料科学 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY

Mechanics of Materials

Pub Date : 2025-12-04 DOI: 10.1016/j.mechmat.2025.105567

Ali Khosravi , Peiman Sharifi , Scott M. Durski , Jennifer Hutchings

Predicting the complete failure behavior of sea ice under varying confinement remains a critical challenge for both engineering design and geophysical modeling. Existing constitutive formulations, such as Mohr–Coulomb, assume linear strength envelopes and therefore cannot capture the nonlinear brittle-to-ductile transition or post-peak strength degradation observed in laboratory tests. To address this limitation, this paper presents a numerical investigation into the compressive behavior of sea ice using the Discrete Element Method (DEM), with a particular emphasis on the effects of confinement and boundary conditions on peak and residual strength. Triaxial compression tests were simulated in PFC^3D using spherical bonded particles and the flat-joint contact model to represent sea ice microstructure. Ice specimens were subjected to a range of confining pressures and boundary conditions varying in wall flexibility and shape to evaluate their influence on both macroscopic strength characteristics and microscale cracking and displacement behavior. For pressure below 3.5 MPa, the DEM model successfully captured the transition from brittle to ductile failure as confinement increased. At low confinement, specimens exhibited abrupt stress drops following peak strength, indicating brittle failure, while higher confinement levels produced gradual softening and elevated residual stresses indicative of ductile response. Microscale analysis confirmed that confinement promotes more distributed cracking and enhanced energy dissipation, stabilizing the post-failure regime. To generalize these findings, a modified Hoek–Brown failure criterion was adapted to characterize sea ice strength behavior under triaxial loading. The model was calibrated using simulation results and experimental data, enabling the derivation of a nonlinear strength envelope and estimation of residual strength as a function of confinement.

预测海冰在不同约束条件下的完全破坏行为仍然是工程设计和地球物理建模的关键挑战。现有的本构公式，如莫尔-库仑，假设线性强度包络，因此无法捕捉实验室测试中观察到的非线性脆性到延性转变或峰后强度退化。为了解决这一限制，本文采用离散元法（DEM）对海冰的压缩行为进行了数值研究，特别强调了约束和边界条件对峰值和残余强度的影响。采用PFC3D模拟三轴压缩试验，采用球形结合颗粒和平面接触模型模拟海冰微观结构。冰试件在不同的围压和边界条件下经受不同的壁面柔韧性和形状，以评估它们对宏观强度特征和微观尺度开裂和位移行为的影响。当压力低于3.5 MPa时，DEM模型成功地捕捉到了约束增加时脆性破坏向延性破坏的转变。在低约束下，试样表现出峰值强度后的突然应力下降，表明脆性破坏，而较高的约束水平产生逐渐软化和残余应力升高，表明韧性响应。微尺度分析证实，约束促进了更分散的开裂，增强了能量耗散，稳定了破坏后的状态。为了推广这些发现，采用了改进的Hoek-Brown破坏准则来表征海冰在三轴载荷下的强度行为。利用仿真结果和实验数据对模型进行了校准，从而推导出非线性强度包络并估计出作为约束函数的残余强度。

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引用次数: 0

A unified thermally activated viscoplastic framework for bitumen failure prediction across various loading paths 一个统一的热激活粘塑性框架，用于沥青在不同加载路径上的破坏预测

IF 4.1 3区材料科学 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY

Mechanics of Materials

Pub Date : 2025-12-03 DOI: 10.1016/j.mechmat.2025.105569

Yankai Wen, Lin Wang

Accurately characterizing bitumen failure under combined thermal and mechanical stresses is key to designing durable pavement systems. This study proposes a unified, physically based framework that incorporates two thermally activated models to characterize the degradation behavior of bitumen. Eyring's stress-assisted molecular flow theory is applied to capture the nonlinear viscoplastic flow behavior under sustained loading, while a modified Arrhenius formulation expressed as a function of stress and temperature is utilized to mechanistically predict failure time. All model parameters are calibrated exclusively using constant-stress creep tests and are subsequently applied without any additional fitting to predict both the evolution of viscoplastic strain and the failure time under strain- and stress-controlled monotonic shear loading tests. Validation across a broad temperature spectrum confirms the model's high accuracy and indicates that viscoplastic deformation and failure are controlled by a common thermally activated mechanism, largely unaffected by the loading path. Minor deviations observed at elevated temperatures indicate the presence of self-healing behavior, suggesting a potential direction for future model refinement. Overall, the proposed framework provides a scalable, mechanistically interpretable, and experimentally efficient approach for reliable binder performance evaluation and performance-based material design.

准确表征沥青在热机械复合应力作用下的破坏是设计耐用路面系统的关键。本研究提出了一个统一的、基于物理的框架，该框架结合了两个热激活模型来表征沥青的降解行为。Eyring的应力辅助分子流动理论用于捕获持续载荷下的非线性粘塑性流动行为，而改进的Arrhenius公式表示为应力和温度的函数，用于机械地预测破坏时间。所有的模型参数都是用恒应力蠕变试验来校准的，然后在没有任何额外拟合的情况下应用，以预测在应变和应力控制的单调剪切加载试验下粘塑性应变的演变和破坏时间。广泛的温度谱验证证实了模型的高精度，并表明粘塑性变形和破坏是由一个共同的热激活机制控制的，在很大程度上不受加载路径的影响。在高温下观察到的微小偏差表明存在自我修复行为，这为未来模型的改进提供了一个潜在的方向。总的来说，所提出的框架为可靠的粘合剂性能评估和基于性能的材料设计提供了一种可扩展的、机械上可解释的、实验上有效的方法。

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引用次数: 0

Global existence and uniqueness of weak solutions for a Willis-type model of elastodynamics 一类willis型弹性动力学模型弱解的整体存在唯一性

IF 4.1 3区材料科学 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY

Mechanics of Materials

Pub Date : 2025-12-01 DOI: 10.1016/j.mechmat.2025.105561

Thomas Blesgen , Patrizio Neff

The existence and uniqueness of weak solutions is shown for a system related to the Willis model of elastodynamics. Both the whole space case and the case of a bounded smooth domain are studied. To this end the equations are reformulated as a linear symmetric hyperbolic system of first order and the existing theory for such systems is applied. If the initial and boundary data is regular enough, classical solutions are obtained. The possibility to transform the problem to a linear symmetric hyperbolic system hinges on a new symmetry condition on the Willis coupling tensor S, not yet considered in the literature. This condition demands that

S

is a totally symmetric third-order tensor.

研究了一类弹性动力学Willis模型系统弱解的存在唯一性。研究了整个空间和有界光滑域的情况。为此，将方程重新表述为一阶线性对称双曲系统，并应用已有的理论。如果初始数据和边界数据足够正则，则得到经典解。将问题转化为线性对称双曲系统的可能性取决于威利斯耦合张量S上的一个新的对称条件，这在文献中尚未考虑。这个条件要求S是一个完全对称的三阶张量。

引用次数: 0

How surface tension influences effective velocities and dispersion of elastic waves in unidirectional porous materials 表面张力如何影响单向多孔材料中弹性波的有效速度和频散

IF 4.1 3区材料科学 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY

Mechanics of Materials

Pub Date : 2025-12-01 DOI: 10.1016/j.mechmat.2025.105564

Hao Hu, Ming Dai, Cun-Fa Gao

Surface stress is known to affect significantly the mechanical behavior of micro- or nano-porous materials. Total surface stress is usually divided into the (initial) surface tension and the surface stretching strain-dependent surface stress related to surface elasticity. The effects of surface elasticity on the effective dynamic properties of porous materials have been well studied in the literature via the use of a simplified version of the Gurtin-Murdoch model which, however, fails to capture corresponding surface tension effects (due to the exclusion of an important surface displacement gradient or equivalently that of the deformation-induced change in the normal direction and curvature of the material surface from this simplified version). In this paper, we employ the complete version of the Gurtin-Murdoch model and the generalized self-consistent method to explore the effects of surface tension on the overall transverse dynamic behavior of a unidirectional porous material. Numerical examples are presented for a soft elastic medium with cylindrical pores at submicron scales. We find that compared with surface elasticity, surface tension plays only a minor role in determining the effective velocity of compressional waves in the microporous medium while it has a comparably significant positive influence on the effective velocity of shear waves (despite the fact that the value of surface tension is much smaller than that of the surface stretching modulus). In particular, we demonstrate that the presence of surface tension reduces significantly the sensitivity of the effective shear-wave velocity to the wave frequency, leading to almost non-dispersive shear wave propagation in the microporous medium in a wide wave-frequency range.

众所周知，表面应力对微孔或纳米孔材料的力学行为有显著影响。总表面应力通常分为（初始）表面张力和与表面弹性有关的与应变相关的表面拉伸应力。通过使用简化版的Gurtin-Murdoch模型，已经在文献中很好地研究了表面弹性对多孔材料有效动态特性的影响，然而，该模型未能捕捉到相应的表面张力效应（由于排除了重要的表面位移梯度，或者等效地排除了变形引起的材料表面法线方向和曲率的变化）。本文采用完整版的Gurtin-Murdoch模型和广义自一致方法，探讨了表面张力对单向多孔材料整体横向动力学行为的影响。给出了具有亚微米尺度柱状孔隙的软弹性介质的数值算例。我们发现，与表面弹性相比，表面张力对微孔介质中纵波有效速度的决定作用较小，而对横波有效速度的影响则相当显著（尽管表面张力的值远小于表面拉伸模量的值）。特别是，我们证明了表面张力的存在显著降低了有效横波速度对波频的敏感性，导致横波在微孔介质中以宽波频范围几乎非色散传播。

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引用次数: 0

Multiscale plasticity in gradient polycrystalline based on discrete dislocation dynamics 基于离散位错动力学的梯度多晶多尺度塑性

IF 4.1 3区材料科学 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY

Mechanics of Materials

Pub Date : 2025-11-28 DOI: 10.1016/j.mechmat.2025.105560

Qing Luo , Qingbing Dong , Xueyu Bai , Wei Min Huang

Materials are naturally polycrystalline, and dislocation-induced plasticity plays a significant role in governing material performance. However, the dislocation evolution involves a complex process of nucleation and annihilation with further interactions when encountering other dislocations and obstacles. In this study, a two-dimensional discrete dislocation dynamic model is developed to study the plastic behavior of gradient polycrystalline, which has been well validated by comparing the solutions with previously reported data. The material hardening mechanism related to grain boundary and obstacle is revealed to be varied with grain size. The gradient yield behavior is investigated for non-uniform grain structure, and the effective grain size is proposed to estimate the yield stress of gradient polycrystalline, which expands the application of the Hall-Petch equation for gradient polycrystalline. The action of local dislocation nucleation is enhanced when subjected to a temperature rise, leading to weaker material strength and the disappearance of the initial pure elastic stage. This study aims to develop a further understanding of the plasticity mechanism and provide valuable insights for the design and optimization of gradient polycrystalline.

材料是天然的多晶材料，位错诱发的塑性对材料的性能起着重要的控制作用。然而，位错的演化是一个复杂的成核和湮灭过程，在遇到其他位错和障碍时还会进一步相互作用。本文建立了一个二维离散位错动力学模型来研究梯度多晶的塑性行为，并通过与先前报道的数据进行比较，得到了很好的验证。结果表明，与晶界和障碍有关的材料硬化机制随晶粒尺寸的变化而变化。研究了非均匀晶粒结构的梯度屈服行为，提出了估计梯度多晶屈服应力的有效晶粒尺寸，拓展了Hall-Petch方程在梯度多晶中的应用。当温度升高时，局部位错形核的作用增强，导致材料强度减弱，初始纯弹性阶段消失。本研究旨在进一步了解梯度多晶的塑性机理，并为梯度多晶的设计和优化提供有价值的见解。

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引用次数: 0

A failure mode dependent damage model with analytical expressions of damage evolution for brittle fiber reinforced composites 基于破坏模式的脆性纤维增强复合材料损伤演化解析模型

IF 4.1 3区材料科学 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY

Mechanics of Materials

Pub Date : 2025-11-27 DOI: 10.1016/j.mechmat.2025.105562

Shubham Rai, Badri Prasad Patel

A 3D failure mode dependent continuum damage model is proposed for brittle fiber-reinforced laminated composites with analytical expressions for coupled damage evolution equations. Two strategies are used to determine coupling vectors (responsible for coupling of damage evolution in different directions): (1) derived from potential functions, and (2) determined from uniaxial and shear experimental stress–strain data. The damage model parameters are determined by minimizing the difference between model predicted and available experimental uniaxial and shear stress–strain curves in the literature. The proposed model captures varying degree of non-linearity in available experimental uniaxial and shear stress–strain curves. The calibrated damage model is employed for progressive failure analysis of moderately thick laminated composite plates using higher-order shear deformation theory with thickness stretch and zig-zag terms. The governing equations are solved using finite element method coupled with Newton–Raphson iterative procedure. It is found that the damage variables based on coupling vectors derived from potential functions are physically consistent unlike coupling vectors obtained from uniaxial and shear stress–strain curves. The proposed model predicts different damage in tension and compression consistent with the strength properties of fiber reinforced composite material in different directions. A parametric study demonstrates the model’s flexibility to match failure loads predicted by existing models in the literature. The model predicted failure loads for notched laminated composite plates under uniaxial tension show good agreement with the experimental results available in the literature.

提出了一种依赖于三维破坏模式的脆性纤维增强层合复合材料连续损伤模型，并给出了耦合损伤演化方程的解析表达式。确定耦合向量（负责不同方向损伤演化的耦合）采用两种策略：(1)由势函数推导，(2)由单轴和剪切实验应力-应变数据确定。损伤模型参数的确定是通过最小化模型预测和现有实验单轴和剪切应力-应变曲线之间的差异来确定的。该模型捕获了现有的单轴和剪切应力-应变曲线的不同程度的非线性。采用校正后的损伤模型，采用高阶剪切变形理论对中厚复合材料层合板的递进破坏进行了分析。采用有限元法结合牛顿-拉夫森迭代法求解控制方程。结果表明，基于势函数的耦合向量的损伤变量与单轴应力-应变曲线和剪切应力-应变曲线的耦合向量在物理上是一致的。该模型在不同方向上预测了与纤维增强复合材料强度特性相一致的拉伸和压缩损伤。参数研究表明，该模型的灵活性，以匹配失效载荷预测现有的模型在文献中。该模型预测的缺口层合板在单轴拉伸作用下的破坏载荷与文献试验结果吻合较好。

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引用次数: 0

A physics-informed neural network model to predict thermo-oxidative/thermal aging of viscoelastic materials 预测粘弹性材料热氧化/热老化的物理信息神经网络模型

IF 4.1 3区材料科学 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY

Mechanics of Materials

Pub Date : 2025-11-25 DOI: 10.1016/j.mechmat.2025.105548

Hossein Naderi, Roozbeh Dargazany

This study introduces a physics-informed machine-learned constitutive model to predict the behavior of viscoelastic materials (VEMs) and their degradation during thermal-oxidative (TO) aging. The framework integrates the eight-chain model with conditional neural networks, enabling the statistical representation of molecular chain dynamics while capturing progressive microstructural changes induced by aging. The complex 3D stress–strain tensor mapping problem has been simplified into a series of super-constrained 1D mapping problems through sequential order reduction. This reduction is achieved using an ensemble of replicated conditional neural network learning agents, each specifically trained to decompose the high-dimensional mapping into distinct 1D problems, each representing a specialized agent. Unlike conventional data-driven approaches, the proposed model embeds physical constraints from polymer chain mechanics and thermodynamics, ensuring both accuracy and consistency. Validation against experimental data demonstrates that the model successfully reproduces the stress–strain response of VEMs and their stiffness changes across different aging levels. This modeling framework will be integrated into the K-Load degradation module developed by Karax LLC¹ to support digital-twin applications for polymeric materials.The developed model (available in GitHub) provides an open-source tool for modeling degradation in polymeric materials and offers a pathway to combining mechanistic constitutive modeling with machine learning.

本研究引入了一种基于物理的机器学习本构模型来预测粘弹性材料（VEMs）的行为及其在热氧化老化（to）过程中的降解。该框架将八链模型与条件神经网络相结合，使分子链动力学的统计表示成为可能，同时捕获由老化引起的渐进微观结构变化。将复杂的三维应力-应变张量映射问题通过序次约简简化为一系列超约束的一维映射问题。这种简化是使用复制的条件神经网络学习代理的集合来实现的，每个代理都经过专门训练，将高维映射分解为不同的1D问题，每个问题代表一个专门的代理。与传统的数据驱动方法不同，该模型嵌入了聚合物链力学和热力学的物理约束，确保了准确性和一致性。实验数据验证表明，该模型能够较好地再现膜片在不同时效水平下的应力应变响应及其刚度变化。该建模框架将集成到Karax LLC1开发的K-Load降解模块中，以支持聚合物材料的数字孪生应用。开发的模型（可在GitHub中获得）为聚合物材料的降解建模提供了一个开源工具，并提供了将机械本构建模与机器学习相结合的途径。

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引用次数: 0

A unified treatment of two-dimensional adhesive contact on a power-law graded elastic half-plane 幂律梯度弹性半平面上二维粘着接触的统一处理

IF 4.1 3区材料科学 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY

Mechanics of Materials

Pub Date : 2025-11-25 DOI: 10.1016/j.mechmat.2025.105559

Fan Xia , Fan Jin

This study develops a unified theoretical solution for two-dimensional (2D) adhesive contact between a power-law graded elastic half-plane and symmetric rigid punches, covering both JKR-type adhesive and non-adhesive conditions. Based on the Betti reciprocal theorem and the generalized Abel transform, closed-form expressions are obtained for surface deformation, pressure distribution, load-displacement relations, and pull-off force. The solution is applied to analyze various punch profiles, such as power-law, cylindrical, optimal, and concave types, highlighting the coupled effects of punch geometry and material gradation on debonding behavior. Classical results for flat, parabolic, and wedge indenters are recovered as special cases. Notably, only the wedge punch exhibits a pull-off force independent of Young’s modulus and Poisson’s ratio in the 2D case, in contrast with the axisymmetric case where only the parabolic punch shows such behavior. For concave indenters, three debonding modes (from edge, center, or full-interface) can be controlled via geometric or gradation parameters. These results provide insights for designing interfacial adhesion through coordinated geometric and material tailoring.

本研究为幂律梯度弹性半平面和对称刚性冲头之间的二维（2D）粘接接触提供了统一的理论解决方案，涵盖了jkr型粘接和非粘接条件。基于Betti互易定理和广义Abel变换，得到了曲面变形、压力分布、载荷-位移关系和拉拔力的封闭表达式。应用该方法分析了幂律型、圆柱型、最优型和凹型等冲孔轮廓，突出了冲孔几何形状和材料级配对脱粘行为的耦合影响。平面、抛物线和楔形压头的经典结果被恢复为特殊情况。值得注意的是，在二维情况下，只有楔形冲头表现出与杨氏模量和泊松比无关的拉离力，而在轴对称情况下，只有抛物线冲头表现出这种行为。对于凹压痕，可以通过几何或渐变参数控制三种剥离模式（从边缘、中心或全界面）。这些结果为通过协调几何和材料剪裁来设计界面粘附提供了见解。

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引用次数: 0

Micromechanical model for multiaxial electromechanical behavior in carbon-black-reinforced elastomers 碳黑增强弹性体多轴电子力学行为的微观力学模型

IF 4.1 3区材料科学 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY

Mechanics of Materials

Pub Date : 2025-11-24 DOI: 10.1016/j.mechmat.2025.105558

Nan Hou , Mahrez Saadedine , Qiang Guo , Karim Kandil , Fahmi Zaïri , Ning Ding

This study presents a comprehensive three-dimensional constitutive model to investigate the interplay between electrical conductivity mechanisms and the biaxial nonlinear mechanical response of carbon-black (CB)-reinforced elastomers. The proposed framework extends previous micromechanical approaches by coupling mechanical reinforcement and electrical transport within a unified continuum description. The reinforcement mechanisms are integrated within a micromechanical framework, capturing near-field direct interactions between CB particles and the surrounding rubber network. Based on Eshelby's inclusion theory, the model explicitly links local stress transfer, interfacial interactions, and particle morphology to the macroscopic response. To account for the hierarchical dispersion of CB, an equivalent particle approach is introduced to represent aggregates, incorporating their size distribution, spatial arrangement, and percolation behavior. The mechanical part of the formulation combines network-based hyperelasticity and viscoelasticity, integrating both the eight-chain and three-chain theories to capture the coupled effects of multiaxiality and inelasticity. The model employs an equivalent circuit tunneling formulation to describe how electrical conductivity evolves with filler content and deformation. This approach establishes a direct correlation between microstructural rearrangements, tunneling resistance, and the progressive breakdown of conductive paths. Progressive damage is incorporated, reflecting CB network breakdown at small deformations and elastomer-filler interface failure at larger deformations. The model capabilities are assessed by analyzing electromechanical performance and failure mechanisms under various deformation modes for styrene-butadiene rubber and natural rubber composites with different CB concentrations. Results demonstrate that the model accurately reproduces the experimentally observed coupling between mechanical reinforcement, conductivity degradation, and deformation mode, highlighting its predictive capability. By integrating micromechanical interactions, network theories, and conduction mechanisms within a single multiscale formulation, this model serves as a robust predictive tool for optimizing conductive elastomers in soft electronics and flexible sensing applications.

本研究提出了一个全面的三维本构模型来研究碳黑（CB）增强弹性体的电导率机制和双轴非线性力学响应之间的相互作用。提出的框架通过在统一的连续体描述中耦合机械强化和电传输来扩展先前的微力学方法。强化机制集成在微机械框架内，捕获CB颗粒与周围橡胶网络之间的近场直接相互作用。该模型基于Eshelby包涵理论，明确地将局部应力传递、界面相互作用和颗粒形态与宏观响应联系起来。为了解释炭黑的分层分散，引入了等效粒子方法来表示聚集体，包括它们的大小分布、空间排列和渗透行为。该公式的力学部分结合了基于网络的超弹性和粘弹性，整合了八链和三链理论，以捕捉多轴性和非弹性的耦合效应。该模型采用等效电路隧道公式来描述电导率如何随填料含量和变形而变化。这种方法建立了微观结构重排、隧道电阻和导电路径逐渐击穿之间的直接关系。渐进式损伤被纳入，反映了CB网络在小变形时的破坏和弹性体-填料界面在大变形时的破坏。通过分析不同CB浓度的丁苯橡胶和天然橡胶复合材料在不同变形模式下的机电性能和失效机理，对模型的能力进行了评估。结果表明，该模型准确再现了实验观察到的力学增强、电导率退化和变形模式之间的耦合，突出了其预测能力。通过将微力学相互作用、网络理论和传导机制集成到一个单一的多尺度公式中，该模型可作为优化软电子和柔性传感应用中导电弹性体的强大预测工具。

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引用次数: 0