Extreme Mechanics Letters最新文献

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

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

Stabilizing the buckling instabilities of soft cylindrical shell grippers 软圆柱壳夹持器屈曲失稳的稳定研究

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

Extreme Mechanics Letters

Pub Date : 2026-01-02 DOI: 10.1016/j.eml.2025.102437

Wenjie Li , Yu Herng Tan , Zhong Wang , Xuguang Dong , Huichan Zhao

Soft cylindrical shell grippers consist of a rigid outer shell and a soft inner layer that inflates inward under internal pressure. This inflatable ring actuator mechanism enables the gripper to conform to and stably grasp objects, offering unique advantages in handling irregular shapes and compliant materials, and making these grippers promising candidates for soft robotic manipulation. However, upon inflation, their soft inner walls often undergo a sequence of buckling instabilities—from wrinkling to creasing and more complex post-buckling behaviors. Due to the stochastic nature of these buckling instabilities, the resulting deformation patterns—such as the number, positions, and deflections of creases—vary unpredictably, leading to inconsistencies in gripper performance. This study investigates the factors governing the buckling instabilities of soft cylindrical shell grippers and proposes strategies for their stabilization. Through theoretical analysis and finite element (FE) simulations, we establish the relationship between geometric parameters and the predicted buckling instabilities. To control the instability morphology, we introduce evenly distributed geometric imperfections and implement a material training process to mitigate non-uniform deformation by leveraging the Mullins effect. We demonstrate that these combined strategies significantly improve grasping performance, including increased contact area, enhanced self-centering, and improved repeatability. Finally, we validate the gripper’s effectiveness in real-world scenarios through on-arm pick-and-place experiments. This work provides a framework for designing soft cylindrical shell grippers with greater reliability, while maintaining simplicity in fabrication.

软圆柱壳夹持器由坚硬的外壳和在内部压力下向内膨胀的软内层组成。这种充气环致动机构使夹持器符合并稳定地抓取物体，在处理不规则形状和柔性材料方面具有独特的优势，并使这些夹持器成为软机器人操作的有希望的候选者。然而，膨胀后，它们柔软的内壁往往经历一系列的屈曲不稳定——从起皱到折痕以及更复杂的后屈曲行为。由于这些屈曲不稳定性的随机性，所产生的变形模式（如折痕的数量、位置和挠度）不可预测地变化，导致夹持器性能不一致。本文研究了软壳夹持器屈曲失稳的影响因素，并提出了其稳定策略。通过理论分析和有限元模拟，建立了几何参数与预测屈曲失稳之间的关系。为了控制不稳定形态，我们引入均匀分布的几何缺陷，并实施材料训练过程，以利用穆林斯效应来减轻不均匀变形。我们证明了这些组合策略显着提高抓取性能，包括增加接触面积，增强自定心和提高可重复性。最后，我们通过手臂拾取和放置实验验证了抓手在现实场景中的有效性。这项工作为设计具有更高可靠性的软圆柱壳夹持器提供了框架，同时保持了制造的简单性。

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引用次数: 0

Front Cover CO1 封面CO1

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

Extreme Mechanics Letters

Pub Date : 2026-01-01 DOI: 10.1016/S2352-4316(26)00001-5

引用次数: 0

Fatigue threshold of dual-crosslinking hydrogels 双交联水凝胶的疲劳阈值

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

Extreme Mechanics Letters

Pub Date : 2025-12-30 DOI: 10.1016/j.eml.2025.102439

Yijian Zheng, Yang Gao, Tongqing Lu

The fatigue threshold of covalent hydrogels follows the Lake-Thomas model, equating to the energy needed to break covalent bonds between crosslinks at the crack tip. Dynamic bonds are widely introduced as secondary crosslinks to toughen hydrogels. Previous studies have reported that dynamic bonds contribute to the fatigue threshold in some tough hydrogels but not in others, making their contribution unclear. In this work, we prepare dual-crosslinking hydrogels (PAV-M²⁺) by introducing ligands along covalent polymer chains, enabling dynamic coordination with various M²⁺ ions to tune the relaxation time. In such hydrogels, we propose that covalent bonds contribute to the fatigue threshold via the Lake-Thomas model, while dynamic bonds contribute based on the competition between relaxation time and the crack-tip strain rate. When the strain rate greatly exceeds the inverse of the relaxation time, dynamic bonds cannot re-associate and contribute little to fatigue threshold. Conversely, when the strain rate is much lower than the inverse of relaxation time, they re-associate reversibly and enhance the threshold. The fatigue threshold of PAV-Ni hydrogels (relaxation time ∼ 300 ms) is 10.5 J/m² at a strain rate of 1 s⁻¹ (consistent with the Lake-Thomas prediction, 9.4 J/m²), and increases to 17.7 J/m² at 0.1 s⁻¹. The fatigue threshold of PAV-Zn hydrogels (relaxation time ∼ 0.3 ms) is 39.8 J/m² at 1 s⁻¹ and 41.4 J/m² at 0.1 s⁻¹, due to the recovery of dynamic bonds during loading cycles. Based on these results, we propose a modified Lake-Thomas model that incorporates the contribution of dynamic bonds to fatigue threshold, capturing the competition between relaxation time and strain rate.

共价水凝胶的疲劳阈值遵循Lake-Thomas模型，等于断裂裂纹尖端交联共价键所需的能量。动态键作为二级交联被广泛引入以增强水凝胶。先前的研究已经报道了动态键对某些坚韧水凝胶的疲劳阈值有贡献，但对其他水凝胶没有贡献，这使得它们的贡献尚不清楚。在这项工作中，我们通过在共价聚合物链上引入配体来制备双交联水凝胶（PAV-M2+），使其能够与各种M2+离子动态配位来调节弛豫时间。在这种水凝胶中，我们提出共价键通过Lake-Thomas模型贡献疲劳阈值，而动态键基于松弛时间和裂纹尖端应变率之间的竞争贡献疲劳阈值。当应变速率大大超过松弛时间的倒数时，动态键不能重新结合，对疲劳阈值的贡献很小。相反，当应变速率远低于松弛时间的倒数时，它们会可逆地重新关联并提高阈值。当应变速率为1 s−1时，PAV-Ni水凝胶的疲劳阈值（松弛时间~ 300 ms）为10.5 J/m2（与Lake-Thomas预测一致，为9.4 J/m2），当应变速率为0.1 s−1时，疲劳阈值增加到17.7 J/m2。由于加载过程中动态键的恢复，PAV-Zn水凝胶的疲劳阈值（松弛时间~ 0.3 ms）在1 s−1时为39.8 J/m2，在0.1 s−1时为41.4 J/m2。基于这些结果，我们提出了一个改进的Lake-Thomas模型，该模型包含了动态键对疲劳阈值的贡献，捕捉了松弛时间和应变速率之间的竞争。

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引用次数: 0

Chebyshev physics-informed Kolmogorov-Arnold networks for diffusion-convection-reaction equation in soft material adhesion system 软材料黏附系统中扩散-对流-反应方程的Chebyshev物理Kolmogorov-Arnold网络

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

Extreme Mechanics Letters

Pub Date : 2025-12-13 DOI: 10.1016/j.eml.2025.102436

Zheyu Dong , Jiabao Bai , Daochen Yin , Kunqing Yu , Siqi Yan , Zhi Sheng , Zheng Jia

Recent advances in soft material adhesion have attracted considerable interest due to their potential implications for various scientific disciplines. Solving the 1D Diffusion-Convection-Reaction Equation (DCR Equation) remains a critical challenge in adhesion systems of soft materials, often hindered by computational complexities. Specifically, solving the 1D DCR Equation is particularly challenging owing to its intrinsic complexity as a nonlinear dynamical system, which is governed by an equation combining temporal evolution with zeroth, first, and second-order spatial differential terms. While substantial progress has been made through both experimental and theoretical approaches, the application of neural network-based methods in this area remains relatively underdeveloped. In this study, we address this gap by introducing, for the first time, Chebyshev physics-informed Kolmogorov-Arnold networks (c-PIKANs) specifically for modeling 1D DCR Equation of soft-material adhesion, a framework that systematically optimizes architecture parameters (learning rate, polynomial order, layer size) to maximize predictive performance. The c-PIKAN architecture outperforms conventional multilayer perceptron (MLP)-based physics-informed neural networks (PINNs) in accuracy and efficiency while requiring a smaller network size. This work paves the way for future applications of Kolmogorov-Arnold Networks (KANs) in soft material mechanics and provides crucial guidance for the adjustment of network hyperparameters, potentially opening new avenues for innovation in the field.

软材料粘附的最新进展由于其对各种科学学科的潜在影响而引起了相当大的兴趣。一维扩散-对流-反应方程（DCR方程）的求解一直是软质材料黏附系统中的一个关键挑战，通常受到计算复杂性的阻碍。具体来说，由于其作为一个非线性动力系统的内在复杂性，求解一维DCR方程尤其具有挑战性，该系统由一个将时间演化与零阶、一阶和二阶空间微分项相结合的方程所控制。虽然通过实验和理论方法取得了实质性进展，但基于神经网络的方法在这一领域的应用仍然相对不发达。在本研究中，我们通过首次引入Chebyshev物理通知Kolmogorov-Arnold网络（c-PIKANs）来解决这一差距，该网络专门用于建模软材料粘附的1D DCR方程，该框架系统地优化了架构参数（学习率，多项式顺序，层大小）以最大化预测性能。c-PIKAN架构在精度和效率方面优于传统的基于多层感知器（MLP）的物理信息神经网络（pinn），同时需要更小的网络规模。这项工作为Kolmogorov-Arnold网络（KANs）在软材料力学中的未来应用铺平了道路，并为网络超参数的调整提供了重要指导，可能为该领域的创新开辟新的途径。

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引用次数: 0

Experimental characterization and modeling anisotropic mechanical responses of liquid crystal elastomers with exchangeable disulfide bonds 具有可交换二硫键的液晶弹性体各向异性力学响应的实验表征和建模

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

Extreme Mechanics Letters

Pub Date : 2025-12-07 DOI: 10.1016/j.eml.2025.102435

Baihong Chen , Huxiao Yang , Rui Xiao

The exchangeable liquid crystal elastomers (LCEs) with dynamic disulfide bonds possess excellent processability, recyclability and room-temperature programmability, making them highly promising for applications in soft robotics and shape-morphing structures. In this work, we combine experimental and theoretical approaches to systematically investigate the effect of programming stretches on the anisotropic mechanical response of LCEs with exchangeable disulfide bonds. We first fabricated a series of monodomain LCEs by applying varying programming stretches using disulfide exchange reactions. The thermal actuation response of these specimens was then characterized. Uniaxial tensile tests were further conducted to elucidate the effects of the programming stretches on the anisotropic mechanical responses at different strain rates. A viscoelastic model is then applied to simulate the anisotropic and rate-dependent mechanical response of monodomain LCEs. The results reveal the existence of a saturation programming stretch. Below this threshold, increasing programming stretches extends the length of the stress plateau, while the plateau stress remains unchanged. Notably, the Young’s moduli along orthogonal directions are identical prior to director rotation, contrasting with conventional two-step polymerized monodomain LCEs. This suggests that the anisotropic modulus of conventional LCEs may originate from the prestretched network. The experimental results also reveal that hysteresis loops under uniaxial loading along the director are larger than those under perpendicular loading. This indicates that the viscosity associated with director rotation is significantly lower than that of network deformation. For the theoretical part, the viscoelastic model with multiple relaxation processes successfully captures the anisotropic and rate-dependent mechanical response of monodomain LCEs, while the model with a single relaxation process fails to predict the area of the hysteresis loop over a wide rate region.

具有动态二硫键的可交换液晶弹性体（LCEs）具有优异的可加工性、可回收性和室温可编程性，在软机器人和变形结构中具有很大的应用前景。在这项工作中，我们结合实验和理论方法系统地研究了规划拉伸对具有交换二硫键的lce各向异性力学响应的影响。我们首先通过使用二硫交换反应应用不同的编程拉伸来制备一系列单畴lce。然后对这些试样的热驱动响应进行了表征。进一步进行了单轴拉伸试验，阐明了不同应变速率下规划拉伸对各向异性力学响应的影响。然后应用粘弹性模型模拟了单畴LCEs的各向异性和速率相关的力学响应。结果表明饱和规划拉伸的存在。在此阈值以下，增加编程拉伸会延长应力平台的长度，而平台应力保持不变。值得注意的是，与传统的两步聚合单畴LCEs相比，在定向旋转之前，沿着正交方向的杨氏模量是相同的。这表明传统LCEs的各向异性模量可能来源于预拉伸网络。实验结果还表明，沿方向单轴加载时的滞回线比垂直加载时的滞回线要大。这表明与导向器旋转相关的粘度明显低于网络变形相关的粘度。在理论部分，具有多个弛豫过程的粘弹性模型成功地捕获了单域LCEs的各向异性和速率相关的力学响应，而具有单一弛豫过程的模型无法在宽速率区域内预测滞后环的面积。

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引用次数: 0

Control of dynamic frictional instability using mechanical metamaterials 利用机械超材料控制动态摩擦不稳定性

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

Extreme Mechanics Letters

Pub Date : 2025-12-03 DOI: 10.1016/j.eml.2025.102428

Sourav Kumar Panja , Kunnath Ranjith

We investigate the control of frictional instabilities at bi-material interfaces using mechanical metamaterials with unconventional dynamic properties. Specifically, we examine two configurations: (i) an anti-plane shear problem involving a metaelastic layer with negative effective density and shear modulus slipping on a classical elastic half-space, and (ii) an in-plane problem where a metaelastic half-space exhibiting triple-negative properties (negative density, bulk modulus, and shear modulus) overlies a conventional elastic half-space. Guided by a linear stability analysis of quasi-static steady sliding, we carry out numerical simulations of spontaneous rupture propagation at the interface with a slip-weakening friction law. This work shows the possibility of rupture arrest or propagation control at bi-material interfaces by negative effective properties of mechanical metamaterial with implications for seismic fault engineering, tribology, and advanced material design.

我们使用具有非常规动态特性的机械超材料研究双材料界面摩擦不稳定性的控制。具体来说，我们研究了两种配置：(i)涉及具有负有效密度和剪切模量的元弹性层在经典弹性半空间上滑动的反平面剪切问题，以及（ii）平面内问题，其中具有三负性质的元弹性半空间（负密度，体模量和剪切模量）覆盖在传统弹性半空间上。在准静态稳态滑动线性稳定性分析的指导下，采用滑移弱化摩擦规律对界面处的自发破裂扩展进行了数值模拟。这项工作显示了通过机械超材料的负有效特性在双材料界面上阻止破裂或控制传播的可能性，这对地震断层工程、摩擦学和先进材料设计具有重要意义。

引用次数: 0