European Journal of Mechanics A-Solids最新文献_第5页

A phase-field model for microstructurally-sensitive crack growth in FCC crystals based on crystal plasticity theory 基于晶体塑性理论的FCC晶体微结构敏感裂纹扩展相场模型

IF 4.2 2区工程技术 Q1 MECHANICS

European Journal of Mechanics A-Solids

Pub Date : 2025-12-23 DOI: 10.1016/j.euromechsol.2025.106007

Hongyi Huang , Zhengbang Ding , Jun Luo

In this paper, a phase field model based on crystal plasticity theory is proposed to characterize the microstructurally-sensitive fatigue and fracture behavior of face-centered cubic crystals (FCC) crystals. The microscopic plastic slip is predicted with a phenomenological crystal plasticity model. The plastic stored energy, along with the tensile part of the decomposed elastic strain energy, is regarded as the crack driving force.The cumulative value of the elastoplastic strain energy is adopted as the damage variable, based on which a fatigue degradation function is introduced to describe the cyclic loading effect. A threshold value of the normalized crack driving force is introduced to mitigate spurious evolution of the crack phase field. Crack growth behavior in FCC single crystals and polycrystals under monotonic and cyclic loading is then studied with phase field modelling. The numerical results indicate that the phase field model can effectively characterize the crystal orientation dependent crack growth in FCC crystals. The predicted crack growth rate conforms to the fundamental characteristics of short fatigue crack growth. The impact of the effective proportion of the accumulated plastic strain energy acting as the crack driving force on the crack growth behavior is discussed in the paper. The numerical findings presented in the paper provide critical insights toward development of a robust numerical approach to characterize the microstructure-sensitive fatigue damage evolution in FCC crystals.

提出了一种基于晶体塑性理论的相场模型来表征面心立方晶体的微结构敏感疲劳和断裂行为。用现象学晶体塑性模型预测微观塑性滑移。将塑性存储能与分解后的弹性应变能中的拉伸部分作为裂纹驱动力。采用弹塑性应变能的累积值作为损伤变量，在此基础上引入疲劳退化函数来描述循环加载效应。引入归一化裂纹驱动力的阈值，以减轻裂纹相场的伪演化。采用相场模型研究了FCC单晶和多晶在单调和循环载荷作用下的裂纹扩展行为。数值结果表明，相场模型可以有效地表征FCC晶体中晶体取向相关的裂纹扩展。预测的裂纹扩展速率符合短疲劳裂纹扩展的基本特征。讨论了累积塑性应变能的有效比例作为裂纹驱动力对裂纹扩展行为的影响。本文提出的数值结果为FCC晶体中微结构敏感疲劳损伤演化的鲁棒数值方法的发展提供了重要的见解。

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引用次数: 0

Quasi-static shape control of structures with topologically complex equilibrium sets 拓扑复杂平衡集结构的准静态形状控制

IF 4.2 2区工程技术 Q1 MECHANICS

European Journal of Mechanics A-Solids

Pub Date : 2025-12-22 DOI: 10.1016/j.euromechsol.2025.106000

Eszter Fehér , András Á. Sipos , Péter L. Várkonyi

Inspired by biological systems, we introduce a general framework for quasi-static shape control of load-bearing structures under slowly varying external actions or requirements. In this setting, shape control aims to traverse the stable sub-manifolds of the equilibrium set to meet some predefined requirements or optimization criteria. This paper explores the implications of large shape changes and high compliance, such as the emergence of unstable equilibria and equilibrium sets with non-trivial topology. We identify various adaptivity scenarios, ranging from inverse kinematics to optimization and path planning problems, and discuss the role of time-dependent loads and requirements. The applicability of the proposed concepts is demonstrated through the example of a soft arch that is susceptible to snap-through behavior.

受生物系统的启发，我们介绍了在缓慢变化的外部作用或要求下，承载结构的准静态形状控制的一般框架。在这种情况下，形状控制的目标是遍历平衡集的稳定子流形，以满足一些预定义的要求或优化准则。本文探讨了大形状变化和高顺应性的含义，如非平凡拓扑的不稳定平衡和平衡集的出现。我们确定了各种适应性场景，从逆运动学到优化和路径规划问题，并讨论了时间相关负载和要求的作用。所提出的概念的适用性是通过一个软拱的例子来证明的，该软拱易受弹跳行为的影响。

引用次数: 0

A nonlinear rigid-flexible piezoelectric beam model for large in-plane motions 大平面内运动的非线性刚柔压电梁模型

IF 4.2 2区工程技术 Q1 MECHANICS

European Journal of Mechanics A-Solids

Pub Date : 2025-12-22 DOI: 10.1016/j.euromechsol.2025.106005

Yanjie Mei , Gongye Zhang , Changwen Mi , Yilin Qu

This research focuses on studying the rigid-flexible dynamic response of piezoelectric beams undergoing large-scale in-plane motion. Utilizing a three-dimensional (3D) framework of the piezoelectric effect, coupled with Euler-Bernoulli beam theory and the principles of rigid-flexible coupling dynamics, a nonlinear one-dimensional (1D) model, which considers the rigid displacement, rotation angle, axial deformation, deflection, and electric potential of the piezoelectric beam, is established. Through meticulous analysis based on the developed model, the paper examines the behavior of several key physical quantities, such as the instantaneous axial deformation, tip deflection, maximum first-order electrical potential, torque, and thrust. These quantities are studied under two typical scenarios—translation and rotation of the component model with the rigid hub. Numerical results show that there is a significant coupling effect between the axial deformation of the piezoelectric beam and its internal first-order potential when there is a large-scale planar motion in the piezoelectric beam. These numerical results indicate that there is a consistent change trend between the instantaneous external force, instantaneous acceleration, axial deformation, deflection and electric potential. These phenomena indicate that the motion state and deformation of the component model can be detected through the electric potential distribution generated in the beam by the piezoelectric effect. This study will provide an important theoretical basis for understanding the electromechanical coupling characteristics of piezoelectric structures in dynamic environments and developing robotic structures accordingly.

本研究的重点是研究大尺度平面内运动压电梁的刚柔动力响应。利用压电效应的三维框架，结合欧拉-伯努利梁理论和刚柔耦合动力学原理，建立了考虑压电梁的刚性位移、旋转角度、轴向变形、挠度和电势的非线性一维模型。通过对所建立模型的细致分析，本文考察了几个关键物理量的行为，如瞬时轴向变形、尖端挠度、最大一阶电势、扭矩和推力。在刚性轮毂的构件模型平移和旋转两种典型情况下，对这些量进行了研究。数值计算结果表明，当压电梁内部存在较大的平面运动时，其轴向变形与其内部一阶势之间存在显著的耦合效应。这些数值结果表明，瞬时外力、瞬时加速度、轴向变形、挠度和电势之间存在一致的变化趋势。这些现象表明，可以通过压电效应在梁内产生的电势分布来检测构件模型的运动状态和变形。该研究将为理解压电结构在动态环境中的机电耦合特性，并据此开发机器人结构提供重要的理论依据。

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引用次数: 0

Estimation of local field statistics in highly filled composites based on an incremental mean-field homogenization scheme 基于增量平均场均匀化方案的高填充复合材料局部场统计估计

IF 4.2 2区工程技术 Q1 MECHANICS

European Journal of Mechanics A-Solids

Pub Date : 2025-12-20 DOI: 10.1016/j.euromechsol.2025.106004

Éléonore Bourdier, Sophie Dartois, Rémi Cornaggia, Renald Brenner

This article addresses the estimation of local field statistics and effective properties of highly filled particulate composites. With this aim in view, use is made of the differential scheme in its incremental form. In this framework, accounting for the successive homogenization steps characteristic of the incremental process, we derive the expressions of first- and second-order moments of intraphase strain fields. For first-order moments, this involves the calculation of the localization tensors for each phase at each step. For the second-order moments, the approach relies on the application of the chain derivation rule throughout the process, making it possible to express the derivatives of the final effective properties as a function of the initial properties of the phases. These expressions have been validated by comparison with available analytical solution for isotropic porous media. Besides, more general microstructures have been considered with phases exhibiting high mechanical contrasts and for a wide range of volume fractions. The numerical results on local field statistics have been compared to other mean-field homogenization schemes, such as the Mori–Tanaka and Lielens models, as well as to full-field simulations on representative microstructures. These comparisons confirm the relevance of the proposed approach in the context of highly inclusionary media.

本文讨论了高填充颗粒复合材料的局部场统计和有效性能的估计。考虑到这一目的，采用增量形式的微分格式。在此框架下，考虑到增量过程的连续均匀化步骤特征，我们推导了相内应变场的一阶和二阶矩的表达式。对于一阶矩，这涉及到在每个步骤中计算每个相位的局部化张量。对于二阶矩，该方法依赖于整个过程中链式推导规则的应用，使得最终有效性质的导数可以表示为相初始性质的函数。通过与现有的各向同性多孔介质解析解的比较，验证了这些表达式的正确性。此外，更一般的微观结构已被考虑与相表现出高机械对比和大范围的体积分数。将局部场统计的数值结果与其他平均场均匀化方案（如Mori-Tanaka和Lielens模型）以及具有代表性的微观结构的全场模拟进行了比较。这些比较证实了所提出的方法在高度包容性媒体背景下的相关性。

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引用次数: 0

Quantitative evaluation of the dependence of the Portevin-Le Chatelier effect on temperature and strain rate in an Al–Mg alloy (AA5083-H111): Insights from machine learning Al-Mg合金（AA5083-H111）中Portevin-Le Chatelier效应对温度和应变速率依赖性的定量评价：来自机器学习的见解

IF 4.2 2区工程技术 Q1 MECHANICS

European Journal of Mechanics A-Solids

Pub Date : 2025-12-18 DOI: 10.1016/j.euromechsol.2025.105989

Angelika Cerny , Manuel Hofbauer , Alois C. Ott , Johannes A. Österreicher

Al–Mg alloys, among others, exhibit the Portevin-Le Chatelier (PLC) effect. In addition to serrations in the stress–strain curve, the PLC effect also manifests itself macroscopically as stretcher strain marks on the workpiece. Therefore, it is of particular interest to predict and quantify the appearance of the PLC effect. In this work, a simple method for calculating the PLC effect strength based on stress–strain curves is presented, which can be used to evaluate the appearance of PLC effect serrations. The influence of different strain rates, temperatures, and holding times on PLC effect serrations is demonstrated using a 5083-H111 alloy. To classify PLC effect occurrence, unsupervised clustering was applied to stress–strain data. Additionally, machine learning models, including Gaussian process regression (GPR) and multilayer perceptron (MLP), were employed to predict the PLC effect based on experimental parameters.

Al-Mg合金表现出波特文-勒夏特列（PLC）效应。除了应力-应变曲线上的锯齿外，PLC效应还在宏观上表现为工件上的拉伸器应变痕迹。因此，预测和量化PLC效应的出现是特别有趣的。本文提出了一种基于应力-应变曲线计算PLC效应强度的简单方法，该方法可用于评估PLC效应锯齿的外观。以5083-H111合金为材料，研究了不同应变速率、温度和保温时间对PLC效应锯齿的影响。为了对PLC效应的发生进行分类，对应力-应变数据进行了无监督聚类。此外，采用机器学习模型，包括高斯过程回归（GPR）和多层感知器（MLP），根据实验参数预测PLC效果。

引用次数: 0

Unveiling the role of peak load in the stability and growth of interlaminar fatigue damage in composite structures 揭示峰值荷载在复合材料结构层间疲劳损伤稳定性和发展中的作用

IF 4.2 2区工程技术 Q1 MECHANICS

European Journal of Mechanics A-Solids

Pub Date : 2025-12-18 DOI: 10.1016/j.euromechsol.2025.106001

Angela Russo, Rossana Castaldo, Aniello Riccio

Understanding the stability of delamination growth is essential for ensuring the reliability of composite structures under compressive fatigue loading. In post-buckling regimes, where crack propagation can become highly unstable and nonlinear, even small variations in the applied load may drastically alter damage evolution and residual strength. Despite its critical role, the stability of interlaminar crack growth under cyclic compression remains poorly understood, demanding refined numerical strategies to capture its complex behaviour. This work addresses this gap by investigating how the peak compressive load influences the stability and progression of delamination in composite structures.

A dedicated numerical approach has been developed to study these effects. The methodology, named SMART LOOP, couples the Virtual Crack Closure Technique (VCCT) with the Paris Law-based damage accumulation model. Such method employs an adaptive timestep strategy to ensure precise load control and mesh-independent predictions. SMART LOOP transforms force-controlled fatigue simulations into a sequence of displacement-controlled static analyses, where the displacement input is automatically adjusted to reach the target load level. This produces delamination length results that are independent of element size, eliminating the need for mesh refinement strategies.

A series of simulations has been carried out on an Omega-stiffened composite panel subjected to three different compressive peak loads (25.2, 27.1, and 29.1 kN). The numerical results have been compared with experimental data from the literature to enhance the understanding of the unstable delamination growth phenomenon. This provides additional insights into failure mechanisms and complements the experimental observations.

了解分层生长的稳定性对于保证复合材料结构在压缩疲劳载荷作用下的可靠性至关重要。在后屈曲状态下，裂纹扩展可能变得高度不稳定和非线性，即使施加载荷的微小变化也可能极大地改变损伤演变和残余强度。尽管层间裂纹在循环压缩下的扩展具有重要作用，但人们对其稳定性的了解仍然很少，因此需要精确的数值策略来捕捉其复杂行为。这项工作通过研究峰值压缩载荷如何影响复合材料结构中分层的稳定性和进展来解决这一空白。一种专门的数值方法被开发出来研究这些影响。该方法名为SMART LOOP，将虚拟裂纹闭合技术（VCCT）与基于巴黎定律的损伤累积模型相结合。该方法采用自适应时间步长策略，以确保精确的负载控制和网格无关的预测。SMART LOOP将力控制的疲劳模拟转换为一系列位移控制的静态分析，其中位移输入被自动调整以达到目标负载水平。这产生了独立于元素大小的分层长度结果，消除了对网格细化策略的需要。对omega -加筋复合材料板进行了一系列模拟，分别承受三种不同的峰值压缩载荷（25.2、27.1和29.1 kN）。将数值结果与文献中的实验数据进行了比较，以加深对不稳定分层生长现象的认识。这为失效机制提供了额外的见解，并补充了实验观察结果。

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引用次数: 0

Accounting for plasticity: An extension of inelastic constitutive artificial neural networks 计算塑性：非弹性本构人工神经网络的扩展

IF 4.2 2区工程技术 Q1 MECHANICS

European Journal of Mechanics A-Solids

Pub Date : 2025-12-18 DOI: 10.1016/j.euromechsol.2025.105998

Birte Boes , Jaan-Willem Simon , Hagen Holthusen

In this work, we extend the framework of inelastic constitutive artificial neural networks (iCANNs) by incorporating plasticity. Thereby, we increase their applicability to capture more complex material behavior by solving the underlying inequality constraints associated with plasticity, aiming to automatically discover the formulation that matches the experimental data most accurately. Learning on stress–strain data, our approach enables the automatic discovery of the constitutive equations for elasto-plastic materials – including the identification of the material parameters and the underlying functional forms of the Helmholtz free energy, yield function and evolution equations for the inelastic deformations including linear and nonlinear kinematic hardening. These are captured using feed-forward neural networks. The proposed methodology ensures objectivity, material symmetry, and thermodynamic consistency, providing a robust and interpretable basis for automatic model discovery at finite strains. Investigation of our model’s prediction showed that the extended iCANNs successfully predict both linear and nonlinear kinematic hardening behavior based on experimental and artificially generated datasets, showcasing promising capabilities of this framework. Nonetheless, challenges remain in fully capturing complex yield criteria – such as those exhibiting tension–compression asymmetry – and predicting complex nonlinear hardening.

在这项工作中，我们通过纳入可塑性扩展了非弹性本构人工神经网络（icann）的框架。因此，我们通过解决与塑性相关的潜在不等式约束来提高它们的适用性，以捕获更复杂的材料行为，旨在自动发现最准确地匹配实验数据的公式。通过学习应力应变数据，我们的方法能够自动发现弹塑性材料的本构方程，包括材料参数的识别和亥姆霍兹自由能的基本函数形式，屈服函数和非弹性变形的演化方程，包括线性和非线性运动硬化。这些都是用前馈神经网络捕获的。所提出的方法确保了客观性、材料对称性和热力学一致性，为有限应变下的自动模型发现提供了可靠和可解释的基础。对我们模型预测的研究表明，扩展的icann成功地预测了基于实验和人工生成的数据集的线性和非线性运动学硬化行为，展示了该框架的良好能力。尽管如此，在充分捕捉复杂的屈服标准（例如那些表现出拉压不对称的屈服标准）和预测复杂的非线性硬化方面仍然存在挑战。

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引用次数: 0

Investigation of energy absorbing performance of Novel hybrid composite tubes with carbon fiber and metallic strip 新型碳纤维-金属带复合材料管吸能性能研究

IF 4.2 2区工程技术 Q1 MECHANICS

European Journal of Mechanics A-Solids

Pub Date : 2025-12-16 DOI: 10.1016/j.euromechsol.2025.106002

Dursun Meriç , Ali Ihsan Budur , Hasan Gedikli

Hybrid composite structures, created by combining different fibers and materials, offer improved mechanical and energy-absorbing properties by balancing the weaknesses of individual materials. The study aims to develop innovative hybrid composite tubes with circular, square, and hexagonal section geometry and to investigate their energy absorption performances. Hybrid composite tubes are manufactured using aluminum (Al6061) and steel (304 L) metal strips with continuous carbon fiber reinforcement in the fiber winding machine. Hybrid composite tubes with one, two and three metal strip layers were produced to examine the effect of the number of metal strip layers on energy absorption performance. As a result of static compression tests, absorbed energy (AE), specific energy absorption (SEA), and peak force criteria were used to evaluate the energy absorption performances of composite and hybrid composite tubes. The results showed that hybrid tubes with one-layer aluminum and one-layer steel metal strip increased AE and SEA values. In contrast, these values decreased in hybrid tubes with two- and three-layer aluminum and steel strips. In addition, it was determined that the peak force values decreased in two- and three-layer hybrid tubes.

混合复合材料结构是由不同的纤维和材料组合而成的，通过平衡单个材料的弱点，提供了更好的机械和吸能性能。该研究旨在开发具有圆形、方形和六边形截面几何形状的新型混合复合材料管，并研究其吸能性能。混合复合管是用铝（Al6061）和钢（304 L）金属带制造的，在纤维缠绕机中有连续的碳纤维增强。制备了一层、两层和三层金属带复合材料管，考察了金属带层数对吸能性能的影响。通过静态压缩试验，采用吸收能（AE）、比能吸收（SEA）和峰值力标准对复合材料管和混合材料管的吸能性能进行了评价。结果表明：一层铝带和一层钢带混合管提高了声发射和声发射强度。相比之下，在两层和三层铝和钢带混合管中，这些值降低了。此外，还确定了两层和三层混合管的峰值力值降低。

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引用次数: 0

Nonlinear dynamic analysis of geometrically exact microshells with flexoelectricity based on weak form quadrature element method 基于弱形式正交元法的几何精密柔电微壳非线性动力学分析

IF 4.2 2区工程技术 Q1 MECHANICS

European Journal of Mechanics A-Solids

Pub Date : 2025-12-16 DOI: 10.1016/j.euromechsol.2025.105985

Tingrui Chen , Jingchun Zhang , Fan Yang , Run Zhang

In this paper, a geometrically exact dynamic shell model incorporating flexoelectricity is developed, along with its formulation based on the weak form quadrature element method. The model accounts for the coupling between the strain gradient and the electric field within the framework of flexoelectricity, including size effects along the thickness direction. The validity and feasibility of the proposed formulation are demonstrated through several numerical examples involving typical geometrically nonlinear dynamic shell problems. Furthermore, the influences of the size-dependent coefficient and the flexoelectric coefficient on the dynamic response of microshell structures are investigated. In contrast to existing flexoelectric shell models, the present model employs a geometrically exact shell theory, providing an innovative framework for analyzing the dynamic behavior of flexoelectric microshells undergoing large displacements and rotations. This study is a step forward to better understand the flexoelectric effects on microshells under large deflections and also provides a feasible method to predict its nonlinear dynamic behaviors.

本文基于弱形式正交元法，建立了包含柔电的几何精确壳层动力学模型，并给出了该模型的表达式。该模型在挠性电的框架内考虑了应变梯度与电场之间的耦合，包括沿厚度方向的尺寸效应。通过几个典型几何非线性动力壳问题的数值算例，验证了所提公式的有效性和可行性。此外，还研究了尺寸相关系数和挠曲电系数对微壳结构动力响应的影响。与现有的柔性电壳模型相比，该模型采用几何精确壳理论，为分析大位移和大旋转下柔性电微壳的动力学行为提供了一个创新的框架。该研究为更好地理解大挠度作用下微壳的挠曲电效应迈出了一步，也为预测微壳的非线性动力学行为提供了一种可行的方法。

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引用次数: 0

Design and nonlinear dynamics of tri-stable piezoelectric vibration energy harvester with a bio-inspired RRS structure 仿生RRS结构三稳定压电振动能量采集器的设计与非线性动力学

IF 4.2 2区工程技术 Q1 MECHANICS

European Journal of Mechanics A-Solids

Pub Date : 2025-12-16 DOI: 10.1016/j.euromechsol.2025.105999

Yanze Wu , Zitai Zeng , Jianyu Sang , Debao Kong , Haipeng Liu , Guangqing Wang

A novel tri-stable piezoelectric vibration energy harvester (PVEH) with a raceway-roller-spring (RRS) structure inspired by soybean pod is proposed for efficient vibration energy harvesting. Its main advantage is that the RRS structure eliminates any use of magnets and can be flexibly designed into various morphologies to achieve the expected nonlinear tri-stability by self-defining the raceway’s coordinates. Firstly, the detailed design steps and nonlinear tri-stability induction mechanism of RRS structure were studied, and then the nonlinear dynamic model of PVEH with RRS structure was derived to explore the system dynamics and harmonic response under sweep frequency and harmonic excitation. Finally, a prototype is manufactured and used for experimental investigation and validation. The results indicate that the PVEH with asymmetrical RRS structure can generate a peak voltage and power of 30.4 V and 241 μW, respectively, achieving the normal power density (NPD) of 4.82 μW mm⁻³.g⁻².Hz⁻¹ over an effective bandwidth of 3.6 Hz (2.4–6 Hz), which is higher than that of the comparisons, meeting the self-powering demands of low-power electronic devices.

为了实现高效的振动能量收集，提出了一种新型的三稳态压电振动能量采集器（PVEH），该采集器采用滚道-滚子-弹簧（RRS）结构。其主要优点是RRS结构消除了任何磁铁的使用，并且可以灵活地设计成各种形态，通过自定义滚道坐标来实现预期的非线性三稳定性。首先，研究了RRS结构的详细设计步骤和非线性三稳定感应机理，然后建立了带有RRS结构的PVEH非线性动力学模型，探讨了扫描频率和谐波激励下的系统动力学和谐波响应。最后，制作了样机并进行了实验研究和验证。结果表明，非对称RRS结构的PVEH峰值电压为30.4 V，峰值功率为241 μW，正常功率密度为4.82 μW mm−3.g−2。Hz−1，有效带宽为3.6 Hz (2.4 ~ 6 Hz)，高于比较值，满足小功率电子设备的自供电需求。

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引用次数: 0