Extreme Mechanics Letters最新文献

Thermal rotation behavior of 3D bimaterial bending-dominated chiral metamaterials 三维双材料弯曲主导手性超材料的热旋转行为

IF 4.5 3区工程技术 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY

Extreme Mechanics Letters

Pub Date : 2026-01-25 DOI: 10.1016/j.eml.2026.102453

Yi Zhang , Wei Zhong Jiang , Xue Gang Zhang , Hui Chen Luo , Xiang Jie Wei , Han Yan , Jun Dong , Xin Ren

Conventional materials exhibit uniformly positive coefficients of thermal expansion (CTE). While anomalous CTE values have been documented, including negative or zero coefficients, the achievable deformation modes remain constrained to the orthogonal direction. Realizing thermally driven rotational or torsional deformation continues to present fundamental challenges. Here, we introduce a design strategy integrating thermostat metal strips into 3D chiral metamaterials. The critical geometrical parameters are analyzed numerically, including tessellating cellular numbers and strips’ relative lengths. An oil bath heating test is conducted to examine the thermal rotating effect of the assembled specimen. Results indicate that the increase in cellular number diminishes the rotating behavior. Enhancing the relevant length of metal strips will enhance intrinsic bending-driven rotating mechanisms, thereby amplifying the angle. A maximum rotating angle of 13.8° is achieved over a temperature range of 25 ℃ to 300 ℃. These findings expand the scope of thermally responsive metamaterials and show the potential application for temperature-sensitive devices in structural engineering.

传统材料表现出均匀的正热膨胀系数（CTE）。虽然记录了异常的CTE值，包括负系数或零系数，但可实现的变形模式仍然限制在正交方向上。实现热驱动的旋转或扭转变形仍然是一个根本性的挑战。本文介绍了一种将恒温金属条集成到三维手性超材料中的设计策略。对关键几何参数进行了数值分析，包括镶嵌细胞数和条带的相对长度。进行了油浴加热试验，以检验装配试件的热旋转效应。结果表明，细胞数的增加使旋转性能降低。增加金属带的相关长度将增强固有的弯曲驱动旋转机构，从而扩大角度。在25℃至300℃的温度范围内，最大旋转角度为13.8°。这些发现扩大了热响应超材料的范围，并显示了在结构工程中温度敏感器件的潜在应用。

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引用次数: 0

Effects of electrolyte infiltration on the cracking of active materials in lithium-ion batteries 电解液浸润对锂离子电池活性物质开裂的影响

IF 4.5 3区工程技术 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY

Extreme Mechanics Letters

Pub Date : 2026-01-21 DOI: 10.1016/j.eml.2026.102452

Yisen Peng , Feng Hao

The cracking of electrode active materials causes capacity fade that is one of the bottlenecks in high-performance battery design. Electrolyte infiltrates surface cracks, increasing electrochemically active area and offering fast pathways for lithium-ion insertion/extraction, while interior cracks hinder lithium-ion diffusion within active materials. However, the theoretical model is still lacking to differentiate electrolyte infiltration into surface crack and interior crack. Herein, a chemo-mechanical phase field model coupling the modified smoothed boundary method (SBM) is established to investigate the effect of electrolyte infiltration on chemo-mechanical responses. Within a unified framework, the proposed model captures the coupled processes of electrolyte infiltration and crack growth by distinguishing between interior and surface cracks and tracking the electrolyte-active material interface. It is found that surface cracks infiltrated by electrolyte enhance the accumulation of lithium ions and stress concentration at the crack tip, which further accelerates fracture propagation. The freshly exposed crack surfaces in turn enable more electrochemical reaction sites and improve rate capability, although the cracks destroy the mechanical integrity of active materials. The voltage jump could be induced by coalescence of surface and interior cracks, accompanying by electrolyte penetration. The proposed model provides insights into the complex interaction of electrolyte infiltration, lithium-ion diffusion, stress evolution, and fracture propagation.

电极活性材料的开裂引起的容量衰减是高性能电池设计的瓶颈之一。电解质渗入表面裂纹，增加了电化学活性面积，为锂离子的插入/提取提供了快速途径，而内部裂纹阻碍了锂离子在活性材料中的扩散。然而，目前还缺乏区分电解液渗入表面裂纹和渗入内部裂纹的理论模型。为此，建立了一种耦合改进光滑边界法（SBM）的化学-力学相场模型，研究了电解质浸润对化学-力学响应的影响。在统一的框架内，该模型通过区分内部和表面裂纹以及跟踪电解质-活性材料界面来捕获电解质渗透和裂纹扩展的耦合过程。研究发现，电解液对表面裂纹的渗透增强了裂纹尖端锂离子的积累和应力集中，进一步加速了裂纹的扩展。尽管裂纹破坏了活性材料的机械完整性，但新暴露的裂纹表面反过来又能产生更多的电化学反应位点并提高反应速率。电压跳变是由表面裂纹和内部裂纹合并引起的，同时伴随着电解液的渗透。该模型提供了电解质渗透、锂离子扩散、应力演化和断裂扩展的复杂相互作用的见解。

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引用次数: 0

Multistable mechanical metamaterials with compatible sensitive actuation and high stability 具有兼容敏感驱动和高稳定性的多稳态机械超材料

IF 4.5 3区工程技术 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY

Extreme Mechanics Letters

Pub Date : 2026-01-15 DOI: 10.1016/j.eml.2026.102450

Xiangyu Guo , Yuanming Xu , Nan Zhu , Hang Xu

Multistable mechanical metamaterials (MMMs) program shape reconfigurations through snap-through transitions between multiple stable states in response to environmental stimuli, such as changes in mechanical load, temperature, or magnetic field. One major unresolved challenge is the trade-off resulting from the inherent coupling between the critical actuation load and the multistability. MMMs that require high actuation loads to snap through exhibit strong mechanical stability but are difficult to trigger and cannot respond to small-amplitude environmental stimuli. In contrast, those that can snap through under low loads become highly susceptible to disturbances and may fail to maintain multistability. This study introduces a tri-beam bistable building block to decouple critical actuation load and structural multistability. The constructed MMMs are capable of programming strain energy barriers into their layouts to achieve multistability under arbitrary actuation loads, even low to near-zero. The mechanical properties and deformation mechanisms of MMMs are investigated via a combination of numerical simulation, analytical modeling, and experimental validation. The proposed heterogeneous discrete assembly strategy integrates rigid and flexible components into MMM unit cells, enabling support-free additive manufacturing of reconfigurable one-directional, planar, and spatial MMMs with near-isotropic mechanical behavior. The developed MMMs exhibit post-manufacturing re-programmable deformation, high compactability, and multi-directional stability.

多稳态机械超材料（MMMs）通过响应环境刺激（如机械负荷、温度或磁场的变化）在多个稳定状态之间的瞬时转换来编程形状重新配置。一个尚未解决的主要挑战是临界驱动负载和多稳定性之间固有耦合的权衡。需要高驱动负载才能通过的mm具有很强的机械稳定性，但难以触发，并且不能响应小幅度的环境刺激。相比之下，那些可以在低负载下快速通过的电路变得非常容易受到干扰，并且可能无法保持多稳定性。本研究引入了一种三梁双稳构件来解耦临界驱动载荷和结构的多重稳定性。所构建的mm能够在其布局中编程应变能屏障，以实现任意驱动载荷下的多稳定性，甚至低至接近零。通过数值模拟、分析建模和实验验证相结合的方法研究了mm材料的力学性能和变形机理。提出的异构离散装配策略将刚性和柔性组件集成到MMM单元格中，使具有近各向同性力学行为的可重构单向、平面和空间mm的无支撑增材制造成为可能。开发的mm具有制造后可重新编程变形，高紧凑性和多向稳定性。

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引用次数: 0

Velocity-controlled acoustic tweezers based on beat-frequency modulated surface acoustic waves for programmable particle manipulation 基于热频调制表面声波的可编程粒子操纵速度控制声镊

IF 4.5 3区工程技术 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY

Extreme Mechanics Letters

Pub Date : 2026-01-15 DOI: 10.1016/j.eml.2026.102451

Duo Xu , Lin Wu , Yuyang Lin , Chunyu Xu , Yongmao Pei

Achieving continuous, real-time control over particle velocity, not merely position, represents a fundamental challenge in acoustic tweezers technology. While substantial research has focused on precise dynamic manipulation, most platforms lack the simplicity and versatility for direct velocity command. Here, we introduce a velocity-controlled acoustic tweezers platform based on beat-frequency modulated surface acoustic waves (SAWs). This system translates a single, straightforward input—frequency difference—into a precise and direct particle velocity output. We demonstrate precise velocity control for diverse modes of motion, including uniform motion and accelerated motion, precise angular steering at arbitrary orientations, and the execution of complex programmable trajectories (e.g., Lissajous curves). In contrast to phase modulation, which achieve particle manipulation through discrete positional updates, the beat-frequency modulation approach establishes a direct and continuous command over particle velocity, fundamentally simplifying the paradigm of velocity control. We also induced bubble cluster oscillation via beat-frequency modulation. This work establishes a simple (utilizing frequency difference as the sole control parameter) yet powerful framework for direct velocity manipulation, with promising applications in targeted drug delivery and tissue engineering.

实现对粒子速度的连续、实时控制，而不仅仅是对粒子位置的控制，是声镊技术面临的一个基本挑战。虽然大量的研究集中在精确的动态操作上，但大多数平台缺乏直接速度命令的简单性和通用性。本文介绍了一种基于热频调制表面声波（SAWs）的速度控制声镊平台。该系统将单一、直接的输入——频率差——转化为精确、直接的粒子速度输出。我们演示了各种运动模式的精确速度控制，包括均匀运动和加速运动，任意方向的精确角度转向，以及复杂可编程轨迹的执行（例如，Lissajous曲线）。相位调制通过离散位置更新实现粒子操纵，而节拍-频率调制方法建立了对粒子速度的直接和连续指挥，从根本上简化了速度控制范式。我们还通过频率调制诱导了气泡团振荡。这项工作建立了一个简单（利用频率差作为唯一的控制参数）但功能强大的框架，用于直接速度操纵，在靶向药物输送和组织工程中有很好的应用前景。

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引用次数: 0

Spatiotemporal mechanical stimuli from dental crypt during tooth development: An integrated experimental and computational study 牙齿发育过程中来自牙隐窝的时空机械刺激：一项综合实验和计算研究

IF 4.5 3区工程技术 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY

Extreme Mechanics Letters

Pub Date : 2026-01-15 DOI: 10.1016/j.eml.2026.102449

Julia Kehl , Hanwen Fan , Xiaqiu Xiao , Vincent Hoefler , Mitesha Saha , Noriaki Ono , Yuxiao Zhou

Tooth eruption and late-stage morphogenesis occur within a mechanically dynamic environment shaped by tooth growth and bone remodeling that changes jawbone geometry, yet the mechanical conditions experienced by developing teeth remain poorly quantified. In this study, we combined in situ mechanical testing with micro-computed tomography (micro-CT) imaging and computational modeling to reveal how stresses and strains are distributed in the jawbone surrounding developing teeth in juvenile pigs. Mechanical testing within a CT scanner, coupled with digital volume correlation, provided full-field three-dimensional deformation and strain maps surrounding the developing tooth. Local elastic moduli and microstructural organization of adjacent bone were quantified using atomic force microscopy, enabling validation of material properties used in computational models. Voxel-based finite element models derived from micro-CT data were then digitally modified to represent earlier developmental stages, allowing prediction of stage-dependent stress and strain as the dental crypt enlarges and biomineralization evolves. Together, these integrated datasets reveal how chewing-level forces applied to the overlying deciduous tooth propagate through the jawbone and influence the mechanical environment of the developing tooth across stages of tooth development.

牙齿出牙和后期形态发生在一个由牙齿生长和骨重塑形成的机械动态环境中，改变了颌骨的几何形状，但牙齿发育过程中所经历的机械条件仍然缺乏量化。在这项研究中，我们将原位力学测试与微计算机断层扫描（micro-CT）成像和计算模型相结合，揭示了幼猪发育中牙齿周围颌骨的应力和应变分布。在CT扫描仪内进行机械测试，再加上数字体积相关，提供了发育中牙齿周围的全场三维变形和应变图。使用原子力显微镜对相邻骨的局部弹性模量和微观结构组织进行了量化，从而验证了计算模型中使用的材料特性。基于体素的有限元模型来源于微ct数据，然后进行数字修改以代表早期发育阶段，从而可以预测随着牙隐窝扩大和生物矿化的发展，阶段相关的应力和应变。总之，这些综合数据集揭示了施加在上覆乳牙上的咀嚼力如何通过颌骨传播，并影响牙齿发育各个阶段的机械环境。

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引用次数: 0

Anomalous thermomechanical actuation of liquid crystal elastomer balloons 液晶弹性体气球的异常热机械驱动

IF 4.5 3区工程技术 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY

Extreme Mechanics Letters

Pub Date : 2026-01-14 DOI: 10.1016/j.eml.2026.102448

Zumrat Usmanova, Ruobing Bai

Elastomeric balloons are widely studied in various soft actuation systems owing to their simplicity and versatility. Recently, balloons made of liquid crystal elastomers (LCEs) stand out with their unconventional, thermal-responsive inflation behaviors due to the intrinsic coupling between directionally ordered liquid crystal mesogens and stretchable polymer networks, offering an attractive way for fast, large, reversible, and stimuli-responsive actuation. However, this thermomechanical coupling, together with their resultant actuation and instability in LCE balloons, remains poorly understood. Here we show the anomalous thermomechanical actuation of a spherical LCE balloon by solving a boundary-value problem based on the well-established quasi-convex elastic energy for polydomain LCE. We modify the elastic energy to ensure its consistency with the classical model by Bladon, Warner, and Terentjev based on freely jointed chains. We predict the thermally modulated pressure-volume response of the LCE balloon, where the peak pressure for snap-through instability depends non-monotonically on temperature. This nonmonotonic dependence originates from the competing temperature-dependent effects of the mesogen order and the network elasticity, which also govern the modulus of the LCE in the nematic phase. Finally, by extending the free energy to a Gent-like model, we quantify the detailed temperature-dependent snap-through behavior, compare multiple performance metrics of spherical and cylindrical balloons, and analyze an envisioned thermally modulated fluid pump across a wide range of operating temperatures.

弹性体气球由于其简单和通用性，在各种软驱动系统中得到了广泛的研究。最近，由液晶弹性体（LCEs）制成的气球因其非常规的热响应膨胀行为而脱颖而出，这是由于定向有序液晶介元与可拉伸聚合物网络之间的内在耦合，为快速、大型、可逆和刺激响应驱动提供了一种有吸引力的方法。然而，这种热-机械耦合，以及它们在LCE气球中的致动性和不稳定性，仍然知之甚少。本文基于已建立的多域LCE准凸弹性能，通过求解边值问题，展示了球形LCE气球的反常热力驱动。我们修改了弹性能，使其与Bladon、Warner和Terentjev基于自由关节链的经典模型保持一致。我们预测了LCE气球的热调制压力-体积响应，其中瞬时穿过不稳定性的峰值压力非单调地依赖于温度。这种非单调依赖源于中介质序和网络弹性的温度依赖效应，这也决定了LCE在向列相的模量。最后，通过将自由能扩展到类似根特的模型，我们量化了详细的温度相关的snap-through行为，比较了球形和圆柱形气球的多个性能指标，并分析了在广泛的工作温度范围内设想的热调制流体泵。

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引用次数: 0

Aperiodic minimal surfaces for high toughness metamaterials 高韧性超材料的非周期极小表面

IF 4.5 3区工程技术 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY

Extreme Mechanics Letters

Pub Date : 2026-01-14 DOI: 10.1016/j.eml.2026.102447

Stephen Daynes

Architected materials based on triply periodic minimal surfaces (TPMS) offer excellent stiffness–weight efficiency but often suffer from anisotropic behaviour and preferential crack paths imposed by their underlying symmetry. This work introduces a new class of aperiodic minimal surface metamaterials constructed through a boundary method-based minimal surface formulation. These geometries preserve continuous curvature while embedding long-range structural disorder, enabling manufacturable three-dimensional metamaterials without repeating units or inter-cell discontinuities. Using a combination of additive manufacturing, mechanical testing, and continuum damage finite element analysis, it is shown that the aperiodic Vertices and Edges-connected topologies achieve 40–80 % higher stiffness, 30–40 % greater strength, and up to 50 % higher toughness. Toughness improvements are driven by the designs’ inherently irregular curvature networks that suppress aligned weakness planes and promote highly tortuous crack paths. Unlike TPMS, which display strong orientation-dependent response, the aperiodic architectures show near-isotropic behaviour under 0° and 45° domain rotations. The results demonstrate that geometric aperiodicity provides an effective route to improving flaw tolerance, delaying catastrophic crack propagation, and achieving superior toughness in minimal surface-based metamaterials. This establishes a design framework for next-generation tough, lightweight structures leveraging aperiodic minimal geometry.

基于三周期最小表面（TPMS）的建筑材料具有优异的刚度-重量效率，但往往受到各向异性行为和其潜在对称性所施加的优先裂纹路径的影响。本文介绍了一类新的非周期极小表面超材料，该材料是通过基于边界法的极小表面公式构造的。这些几何形状保留了连续的曲率，同时嵌入了远程结构紊乱，使可制造的三维超材料没有重复单元或胞间不连续。结合增材制造、机械测试和连续损伤有限元分析，结果表明，非周期顶点和边缘连接拓扑结构的刚度提高了40-80 %，强度提高了30-40 %，韧性提高了50 %。韧性的提高是由设计固有的不规则曲率网络驱动的，这种网络抑制了对齐的弱点面，并促进了高度弯曲的裂纹路径。与TPMS表现出强烈的方向依赖性响应不同，非周期结构在0°和45°域旋转下表现出近各向同性行为。结果表明，几何非周期性为提高表面基超材料的裂纹容限、延迟灾难性裂纹扩展和获得优异韧性提供了有效途径。这为利用非周期最小几何形状的下一代坚固、轻量化结构建立了设计框架。

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引用次数: 0

Conditional diffusion modeling for constructing geometrical connectivity in multiscale metamaterial system 构造多尺度超材料系统几何连通性的条件扩散建模

IF 4.5 3区工程技术 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY

Extreme Mechanics Letters

Pub Date : 2026-01-10 DOI: 10.1016/j.eml.2026.102446

Hao Wu , Chen Yu , Chuang Liu , HengAn Wu

Designing multiscale metamaterial systems necessitates the creation of microstructures with compatible boundaries to achieve desired elastic properties induced by topological optimization. However, fulfilling these multiple target requirements remains a significant challenge when designing microstructures with compatible boundaries. To address these issues, we propose a data-driven framework leveraging a conditional diffusion model for the inverse design of microstructures with specific elastic properties and geometrical boundary constraints. Utilizing a large dataset of microstructures generated via topological optimization, our generative model accurately produces diverse geometrical designs for target elastic properties, providing a broad design space for boundary compatibility. The model's accuracy in designing microstructures surpasses that of previous studies. We comprehensively study the relationships between elastic properties and varying ranges of geometrical boundary shapes. Moreover, by incorporating boundary constraints during generation, the proposed BoundaryDiff method ensures mechanical consistency from microscale units to macroscale assemblies. Numerical experiments show that stitched structures generated by our model maintain homogenized elastic properties in close agreement with theoretical predictions, effectively addressing incompatibilities between adjacent microstructures. A numerical case demonstrates the feasibility of our approach in designing multiscale metamaterial systems. This study bridges the gap between microstructure design and topological optimization, holding significant promise for designing functional multiscale metamaterial systems.

设计多尺度超材料系统需要创建具有兼容边界的微结构，以实现由拓扑优化引起的所需弹性性能。然而，在设计具有兼容边界的微结构时，满足这些多目标需求仍然是一个重大挑战。为了解决这些问题，我们提出了一个数据驱动的框架，利用条件扩散模型来逆设计具有特定弹性特性和几何边界约束的微结构。利用通过拓扑优化生成的大型微结构数据集，我们的生成模型精确地生成目标弹性特性的各种几何设计，为边界兼容性提供了广阔的设计空间。该模型在微观结构设计方面的精度超过了以往的研究。我们全面研究了弹性特性与几何边界形状变化范围之间的关系。此外，通过在生成过程中引入边界约束，所提出的BoundaryDiff方法确保了从微观单元到宏观尺度组件的力学一致性。数值实验表明，该模型生成的缝合结构保持了均匀的弹性特性，与理论预测非常吻合，有效地解决了相邻微观结构之间的不相容问题。数值算例验证了该方法在设计多尺度超材料系统中的可行性。该研究弥合了微观结构设计和拓扑优化之间的差距，为设计功能多尺度超材料系统带来了重大希望。

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引用次数: 0

Force-facilitated rare thermally activated bond rupture enables stress relaxation and hysteresis in hydrogel elastomers 力促进的罕见热激活键断裂使水凝胶弹性体的应力松弛和滞后

IF 4.5 3区工程技术 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY

Extreme Mechanics Letters

Pub Date : 2026-01-08 DOI: 10.1016/j.eml.2026.102443

Chih-Jung Lin , Heng-Kwong Tsao , Yu-Jane Sheng

Hydrogel elastomers display stress relaxation, hysteresis, and the Mullins effect even in highly crosslinked networks where chain mobility is strongly suppressed, yet their microscopic origin remains elusive. Although bond rupture has been recognized as a possible contributor, its temporal and spatial occurrence under applied force has not been clearly elucidated. Dissipative particle dynamics simulations with bond-rupture capability reproduce the macroscopic responses, attributed to rare rupture events in tensile strands. Rupture does not result from direct mechanical fracture but from thermal fluctuations that surpass a stress-lowered energy barrier, initiating network reconfiguration that relaxes stress and produces hysteresis. Microscopic variations in mean bond length quantitatively mirror macroscopic stress evolution, ruling out viscoelastic dissipation as the primary mechanism. Our results establish thermally activated bond rupture as the unifying microscopic origin of stress relaxation and hysteresis in hydrogel elastomers, linking microscopic bond dynamics to macroscopic stress responses under cyclic deformations.

水凝胶弹性体即使在链迁移率受到强烈抑制的高度交联网络中也表现出应力松弛、滞后和穆林斯效应，但其微观起源仍然难以捉摸。虽然粘结断裂已被认为是一个可能的因素，但其在施加力作用下的时间和空间发生情况尚未清楚阐明。耗散粒子动力学模拟与键断裂能力再现宏观响应，归因于罕见的断裂事件在拉伸股。破裂不是由直接的机械断裂引起的，而是由超过应力降低的能量势垒的热波动引起的，从而引发网络重构，从而松弛应力并产生滞后。平均键长的微观变化定量地反映了宏观应力演化，排除了粘弹性耗散作为主要机制的可能性。我们的研究结果表明，热激活键断裂是水凝胶弹性体中应力松弛和滞后的统一微观起源，将微观键动力学与循环变形下的宏观应力响应联系起来。

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引用次数: 0

Unified data-driven constitutive modeling of mechanical metamaterials across truss, shell, and plate topologies 跨桁架、壳和板拓扑结构的统一数据驱动的机械超材料本构建模

IF 4.5 3区工程技术 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY

Extreme Mechanics Letters

Pub Date : 2026-01-08 DOI: 10.1016/j.eml.2025.102438

Paul P. Meyer, Thomas Tancogne-Dejean, Dirk Mohr

The macroscopic large deformation response of mechanical metamaterials is governed by the stress distribution within their evolving mesostructures in addition to the elasto-plastic behavior of their constituent solid phase. As a consequence, their homogenized stress-strain response exhibits features of combined isotropic, kinematic and distortional hardening. To investigate the mechanical behavior of lattice materials, we build finite element models of the representative unit cell (RUC) of truss, shell and plate lattices of cubic symmetry. Training data sets are generated comprised of random walk type of strain paths in 6D (input sequences) and the corresponding macroscopic stress histories (output sequences). A comprehensive hyperparameter study exploring the effects of network architecture, training data set size and strain path characteristics, revealed that a compact minimal state cell (MSC) model with only 5000 parameters achieves excellent generalization after training on merely 6000 sequences. Using the same fixed architecture, the model is successfully trained and validated for FCC-truss lattices, BCC-shell lattices and FCC/SC-plate lattices. For reference, the anisotropic Deshpande-Fleck plasticity model is calibrated to the same data. The comparison illustrates the remarkably high predictive accuracy of the data-driven framework, demonstrating its potential as general surrogate modeling strategy for complex lattice metamaterials. The MSC model’s applicability to large-scale analysis is also demonstrated through hemispherical punch indentation, where MSC simulations with a few thousand solid elements reproduce the response of a detailed shell model with millions of elements.

力学超材料的宏观大变形响应不仅受其组成固相的弹塑性行为的影响，还受其演化的细观结构内的应力分布的影响。因此，它们的均匀应力应变响应表现出各向同性、运动硬化和变形硬化相结合的特征。为了研究晶格材料的力学行为，我们建立了立方体对称桁架、壳和板晶格的代表性单元格（RUC）的有限元模型。训练数据集由6D中随机游走型应变路径（输入序列）和相应的宏观应力历史（输出序列）组成。一项综合的超参数研究探索了网络结构、训练数据集大小和应变路径特征的影响，结果表明，只有5000个参数的紧凑最小状态单元（MSC）模型在仅仅6000个序列上训练后就能获得很好的泛化效果。采用相同的固定结构，对FCC-桁架晶格、bcc -壳晶格和FCC/ sc -板晶格进行了成功的训练和验证。作为参考，将各向异性Deshpande-Fleck塑性模型校准为相同的数据。比较说明了数据驱动框架的非常高的预测精度，证明了它作为复杂晶格超材料的通用代理建模策略的潜力。MSC模型对大规模分析的适用性也通过半球形冲孔压痕得到了证明，其中具有数千个固体单元的MSC模拟再现了具有数百万个单元的详细壳模型的响应。

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引用次数: 0