Extreme Mechanics Letters最新文献_第8页

Magnetic field induced toughening mechanisms in isotropic and anisotropic soft magnetoactive elastomers 各向同性和各向异性软磁活性弹性体的磁场诱导增韧机制

IF 4.3 3区工程技术 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY

Extreme Mechanics Letters

Pub Date : 2025-06-23 DOI: 10.1016/j.eml.2025.102368

Nusrat Jahan Salim, Ignacio Arretche, Kathryn H. Matlack

Soft magnetoactive elastomers (sMAEs) are promising multifunctional composites obtained by embedding soft-magnetic particles into an elastomer matrix. Under external magnetic fields, these composites exhibit tunability in mechanical and rheological properties, including stiffness modulation and controllable deformation. Despite growing interest in their magneto-mechanical capabilities, the fracture behavior of sMAEs under magnetic fields remains entirely unexplored. Here, we present the first comprehensive experimental characterization of the fracture toughness and underlying fracture mechanisms in sMAEs subjected to magnetic fields. The study includes different volume fractions of particles, with particles arranged both randomly and aligned, parallel and perpendicular to the loading direction. Experimental results show that in the presence of a magnetic field, fracture toughness increases by 42% for anisotropic sMAEs and 23% for isotropic sMAEs, compared to their unmagnetized states. With the aid of the load-stretch curves, spatial distribution of strain from Digital Image Correlation (DIC), and optical microscopy images of the test specimens, we identify two key mechanisms driving the observed toughening: bulk magneto-mechanical induced stiffening and/or local magneto-mechanical coupling near the crack tip that delays catastrophic failure. This work bridges a critical knowledge gap and expands the design space for durable and adaptive multifunctional magneto-responsive composites.

软磁活性弹性体（sMAEs）是一种很有前途的多功能复合材料，它将软磁颗粒嵌入弹性体基体中。在外加磁场作用下，复合材料表现出力学和流变性能的可调性，包括刚度调制和变形可控。尽管人们对它们的磁机械性能越来越感兴趣，但它们在磁场下的断裂行为仍然完全未被探索。在这里，我们提出了第一个综合的实验表征的断裂韧性和潜在的断裂机制，在磁场作用下的中小微材料。研究中包含了不同体积分数的颗粒，颗粒的排列有随机的也有排列的，平行于加载方向的也有垂直于加载方向的。实验结果表明，在磁场作用下，各向异性微晶合金的断裂韧性比未磁化状态分别提高了42%和23%。借助载荷-拉伸曲线、数字图像相关（DIC）应变的空间分布以及试样的光学显微镜图像，我们确定了驱动所观察到的增韧的两个关键机制：体磁力诱导的增韧和/或裂纹尖端附近的局部磁力耦合，延迟了灾难性破坏。这项工作弥补了关键的知识差距，扩大了耐用和自适应多功能磁响应复合材料的设计空间。

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引用次数: 0

Twist deformation of physical trefoil knots 物理三叶结的捻度变形

IF 4.3 3区工程技术 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY

Extreme Mechanics Letters

Pub Date : 2025-06-23 DOI: 10.1016/j.eml.2025.102369

Taiki Goto , Shunsuke Nomura , Tomohiko G. Sano

Knots across various length scales, from micro to macro-scales, such as polymers, DNA, shoelaces, and surgery, serving their unique mechanical properties. The shapes of ideal knots have been extensively studied in the context of knot theory, while those of physical knots have only been recently discussed in the literature. The complex interplay of elasticity and geometry, such as bending, twisting, and contact, needs to be disentangled to predict their deformation. Still, the unified understanding of the deformation of physical knots is insufficient. Here, we focus on the trefoil knot, a closed knot with a nontrivial topology, and study the relationship between the shapes of the trefoil knot and applied physical twists, combining experiments and simulations. As we twist the elastomeric rod, the knot becomes either tightened or loosened, preserving the original three-fold symmetry, and then buckles and exhibits symmetry breaking at critical angles. The curvature profiles computed through the X-ray tomography (

μ

CT) analysis also exhibit similar symmetry breaking. The transition would be triggered by the mechanical instability, where the imposed twist energy is converted into the bending energy. The phase transition observed here is analogous to the classical buckling phenomena of elastic rings known as the Michell instability. We find that the twist buckling instability of the trefoil knot results from the interplay of bending, twisting, and contact properties of the rod. In other words, the buckling of the knot is predictable based on the elasticity and geometry of rods, which would be useful in avoiding or even utilizing their buckling in practical engineering applications such as surgery and the shipping industry.

从微观到宏观的各种长度尺度的结，如聚合物、DNA、鞋带和手术，都具有独特的机械性能。在结理论的背景下，理想结的形状已经得到了广泛的研究，而物理结的形状最近才在文献中得到讨论。弹性和几何的复杂相互作用，如弯曲、扭曲和接触，需要解开纠缠，以预测它们的变形。然而，对物理结变形的统一认识是不够的。本文以具有非平凡拓扑结构的三叶结为研究对象，结合实验和仿真，研究了三叶结形状与应用物理扭转之间的关系。当我们扭动弹性体杆时，结要么变紧，要么变松，保持原来的三重对称，然后在临界角度弯曲并呈现对称性破坏。通过x射线断层扫描（μCT）分析计算的曲率分布也表现出类似的对称性破缺。这种转变将由机械不稳定性触发，其中施加的扭转能转化为弯曲能。这里观察到的相变类似于称为米歇尔不稳定性的弹性环的经典屈曲现象。研究发现，三叶结的扭转屈曲失稳是由杆的弯曲、扭转和接触性能共同作用的结果。换句话说，基于杆的弹性和几何形状，结的屈曲是可预测的，这将有助于避免甚至利用其在实际工程应用中的屈曲，如外科手术和航运业。

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引用次数: 0

Soft stretchable topological adhesion of hydrogels 水凝胶的柔软可拉伸拓扑粘附

IF 4.3 3区工程技术 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY

Extreme Mechanics Letters

Pub Date : 2025-06-20 DOI: 10.1016/j.eml.2025.102373

Daochen Yin, Jie Ma, Zihang Shen, Zhi Sheng, Yuren Yin, Zheng Jia

Hydrogels are often stretchable and soft. Therefore, when two hydrogels are bonded by an adhesive, the adhesive layer should be stretchable so as not to degrade adhesion during stretching, and should also be soft so as not to affect the mechanical properties (e.g., stress-stretch relationship, modulus, and stretch at rupture) of the hydrogel adherends. Topological adhesion has been one of the state-of-the-art adhesion methods for bonding hydrogels, and stretchable topological adhesion (STA) has been well documented in the literature. However, topological hydrogel adhesion that is both stretchable and soft has not been achieved yet. Here, we demonstrate a soft stretchable topological adhesion (SSTA) strategy using long and flexible stitching polymers that can form topological entanglements with the adherend network as the adhesive. Experimental results indicate that the topological adhesion produced by the SSTA strategy is stretchable, i.e., the adhesion energy is insensitive to applied stretches, and soft, i.e., the application of the adhesive does not alter the stress-stretch relationship, modulus, and stretch at rupture of the hydrogel adherends, which is not possible with existing STA methods for hydrogels. A resistive strain sensor and a soft gripper integrated by the SSTA method are demonstrated.

水凝胶通常具有可拉伸性和柔软性。因此，当两个水凝胶通过粘合剂粘合时，粘合剂层应具有可拉伸性，以免在拉伸过程中降低附着力；同时粘合剂层也应具有柔软性，以免影响水凝胶粘附物的力学性能（如应力-拉伸关系、模量、断裂拉伸）。拓扑粘附一直是最先进的粘合水凝胶的方法之一，可拉伸拓扑粘附（STA）已经在文献中得到了很好的记录。然而，既可拉伸又柔软的拓扑水凝胶粘附尚未实现。在这里，我们展示了一种柔软的可拉伸拓扑粘附（SSTA）策略，使用长而灵活的拼接聚合物，可以与粘附网络形成拓扑纠缠作为粘合剂。实验结果表明，SSTA策略产生的拓扑粘附是可拉伸的，即粘附能对施加的拉伸不敏感，并且是柔软的，即粘合剂的应用不会改变水凝胶粘附物的应力-拉伸关系、模量和破裂时的拉伸，这是现有的水凝胶STA方法所无法实现的。介绍了一种采用SSTA方法集成的电阻式应变传感器和软夹持器。

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引用次数: 0

Designing hyperelastic and adhesive heterogeneous polymer networks under shear conditions 在剪切条件下设计超弹性和粘接的非均相聚合物网络

IF 4.3 3区工程技术 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY

Extreme Mechanics Letters

Pub Date : 2025-06-20 DOI: 10.1016/j.eml.2025.102374

Haowei Ruan , Ping Zhang , Canhui Yang

Strong adhesion and low hysteresis are essential for the applications of soft polymeric adhesives, but unifying them is challenging due to their contradictory relations with network structures. In this study, we investigate the design principles of hyperelastic and adhesive heterogeneous polymer networks under shear conditions. The heterogeneous polymer networks, composed of two adhesive layers sandwiching a hyperelastic bulk, which are in series upon shear, are generally adhesive but hysteretic. Our theoretical analysis shows that a large thickness ratio and a small shear modulus ratio between the hyperelastic bulk and the adhesive surface are crucial for minimizing hysteresis. We verify the principles by synthesizing heterogeneous polymer networks consisting of a layer of PBA sandwiched between two layers of P(BA-co-IBA-co-AA) and examining their hysteresis via cyclic shear tests. The theoretical predictions agree well with experimental results. We further show that the design criteria for low hysteresis also apply to achieving high creep recovery. This work provides mechanistic insights into the rational design and synthesis of soft polymeric adhesives for applications in flexible electronics, soft robotics, and beyond, where shear loads prevail, and strong adhesion and low hysteresis are mission-critical.

强附着力和低迟滞是软性高分子胶粘剂应用的必要条件，但由于它们与网络结构的矛盾关系，统一它们是具有挑战性的。在这项研究中，我们研究了剪切条件下超弹性和粘接非均相聚合物网络的设计原则。非均相聚合物网络由两个胶粘剂层夹在一个超弹性体中组成，它们在剪切时是串联的，通常是粘着的，但是滞后的。我们的理论分析表明，大的厚度比和小的剪切模量比在超弹性体和粘接表面之间是最小化迟滞的关键。我们通过合成由一层PBA夹在两层P（BA-co-IBA-co-AA）之间组成的非均相聚合物网络来验证这些原理，并通过循环剪切测试检测了它们的滞后性。理论预测与实验结果吻合良好。我们进一步表明，低迟滞的设计准则也适用于实现高蠕变恢复。这项工作为柔性电子、软机器人等领域的软聚合物粘合剂的合理设计和合成提供了机械见解，在这些领域，剪切载荷普遍存在，强附着力和低迟滞是关键任务。

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引用次数: 0

Stable self-rotation of liquid crystal elastomer radiating spokes under constant illumination 恒定光照下液晶弹性体辐射辐条的稳定自旋

IF 4.3 3区工程技术 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY

Extreme Mechanics Letters

Pub Date : 2025-06-20 DOI: 10.1016/j.eml.2025.102375

Huili Dong , Pengsen Xu , Ming Wang

A self-excited system obtains energy from a stable external stimulus and generates and sustains oscillations through its internal mechanisms. However, these oscillations may be detrimental to the stable operation of the structure and can result in fluctuating friction. For enhancing system stability and reducing friction fluctuations, we constructed a stable self-rotation system with liquid crystal elastomer (LCE) radiating spokes under constant illumination. In this paper, we achieve continuous modeling of the illumination distribution by introducing an activation function. Based on the LCE photothermally-responsive model, the temperature field in the LCE rods was analyzed. The actuating rotating moment for the self-rotation of the radiating spokes is generated by the shift in the center of mass due to the photothermally-responsive contraction of the LCE. Subsequently, we provided the equilibrium equation and critical condition for stable self-rotation. Under the mutual influence of the temperature field and the actuating rotating moment, the system eventually achieves stable self-rotation. The system absorbs heat to offset damping dissipation, maintaining continuous self-rotation. Numerical simulations indicate that the stable angular velocity is influenced by parameters including heat flux, contraction coefficient, damping rotating moment, illumination zone, and gravitational acceleration. This stable self-rotation system with LCE radiating spokes shows great promise in soft robotics and energy harvesting due to its low friction fluctuations and high stability.

自激系统从稳定的外部刺激中获得能量，并通过其内部机制产生和维持振荡。然而，这些振荡可能不利于结构的稳定运行，并可能导致波动摩擦。为了提高系统稳定性和减小摩擦波动，我们构建了恒定光照下液晶弹性体（LCE）辐射辐条稳定自旋转系统。在本文中，我们通过引入激活函数来实现光照分布的连续建模。基于LCE光热响应模型，分析了LCE棒内的温度场。辐射辐条自旋的驱动力矩是由LCE的光热响应性收缩引起的质心位移产生的。然后给出了稳定自旋的平衡方程和临界条件。在温度场和驱动力矩的共同影响下，系统最终实现稳定的自旋转。系统吸收热量来抵消阻尼耗散，保持连续的自旋转。数值模拟表明，稳定角速度受热流密度、收缩系数、阻尼力矩、光照区和重力加速度等参数的影响。由于低摩擦波动和高稳定性，这种具有LCE辐射辐条的稳定自旋转系统在软机器人和能量收集方面具有很大的应用前景。

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引用次数: 0

Exploring the mechanical properties of aperiodic monotile composite family through Gaussian process regression 利用高斯过程回归研究非周期单瓦复合材料族的力学性能

IF 4.3 3区工程技术 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY

Extreme Mechanics Letters

Pub Date : 2025-06-12 DOI: 10.1016/j.eml.2025.102370

Jiyoung Jung, Kundo Park, Grace X. Gu

The discovery of the first aperiodic monotile has led to the identification of a family of aperiodic monotiles with varying shape parameters that adjust the length ratio between edges. This finding has inspired the development of novel materials utilizing the structure, with significant interest in its distinctive characteristics. However, while previous studies have primarily focused on the unique features of the aperiodic monotile structures, no systematic studies have been conducted to address the statistical aspects induced by their aperiodic nature, such as the variation in mechanical properties due to the translation and orientation of the pattern. In real-world applications, understanding the statistical variance in the mechanical properties of aperiodic monotiles is crucial for ensuring the reliability and robustness of engineering designs. Motivated by these gaps, we present a Gaussian process regression-based framework to predict the mechanical properties of aperiodic monotile composites for given input parameters, as well as the variance in mechanical properties with respect to different arrangements of the pattern. Validation of the model confirms its ability to successfully predict the mechanical properties and their variance. The proposed regression model is then used to explore the continuous design space of aperiodic monotile composites, revealing that patterns with a tuned shape parameter can offer superior load-bearing capabilities of reinforcements compared to other patterns with different shape parameters. This study contributes to the development of novel composite structures by incorporating both the unique design features and the statistical variation inherent in aperiodic monotile designs.

第一个非周期单片的发现导致了一系列非周期单片的识别，这些单片具有不同的形状参数，可以调节边缘之间的长度比。这一发现激发了利用该结构开发新型材料的灵感，并对其独特的特性产生了极大的兴趣。然而，虽然以前的研究主要集中在非周期单瓦结构的独特特征上，但尚未进行系统的研究来解决由其非周期性质引起的统计方面的问题，例如由于图案的平移和取向而引起的力学性能的变化。在实际应用中，了解非周期单块材料力学性能的统计方差对于确保工程设计的可靠性和鲁棒性至关重要。在这些空白的激励下，我们提出了一个基于高斯过程回归的框架来预测给定输入参数下非周期单瓦复合材料的力学性能，以及力学性能随图案不同排列的变化。该模型的验证证实了其成功预测力学性能及其方差的能力。利用所提出的回归模型对非周期单瓦复合材料的连续设计空间进行了探索，结果表明，与具有不同形状参数的其他图案相比，具有调谐形状参数的图案可以提供更好的增强筋承载能力。本研究结合了非周期单片设计的独特设计特征和固有的统计变异，有助于新型复合材料结构的发展。

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引用次数: 0

Inverse design of nonlinear mechanics of bio-inspired materials through interface engineering and Bayesian optimization 基于界面工程和贝叶斯优化的仿生材料非线性力学反设计

IF 4.3 3区工程技术 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY

Extreme Mechanics Letters

Pub Date : 2025-06-10 DOI: 10.1016/j.eml.2025.102359

Wei Zhang , Mingjian Tang , Haoxuan Mu , Xingzi Yang , Xiaowei Zeng , Rui Tuo , Wei (Wayne) Chen , Wei Gao

In many biological materials such as nacre and bone, the material structure consists of hard grains and soft interfaces, with the interfaces playing a significant role in the material’s mechanical behavior. This type of structures has been utilized in the design of various bio-inspired composite materials. Such applications often require the materials to exhibit a specified nonlinear stress–strain relationship. A key challenge lies in identifying appropriate interface properties from an infinite search space to achieve a given target stress–strain curve. This study introduces a Bayesian optimization (BO) framework specifically tailored for the inverse design of interfaces in bio-inspired composites. As a notable advantage, this method is capable of expanding the design space, allowing the discovery of optimal solutions even when the target curve deviates significantly from the initial dataset. Furthermore, our results show that BO can identify distinct interface designs that produce similar target stress–strain responses, yet differ in their deformation and failure mechanisms. These findings highlight the potential of the proposed BO framework to address a wide range of inverse design challenges in nonlinear mechanics problems.

在珍珠质、骨等生物材料中，材料结构由硬颗粒和软界面组成，界面对材料的力学行为起着重要作用。这种类型的结构已被用于各种仿生复合材料的设计中。这种应用通常要求材料表现出特定的非线性应力-应变关系。一个关键的挑战在于从无限搜索空间中确定适当的界面属性，以获得给定的目标应力-应变曲线。本研究介绍了一种贝叶斯优化（BO）框架，专门用于仿生复合材料界面的逆向设计。作为一个显著的优势，该方法能够扩展设计空间，即使目标曲线与初始数据集显著偏离，也可以发现最优解。此外，我们的研究结果表明，BO可以识别出不同的界面设计，这些设计产生相似的目标应力-应变响应，但其变形和破坏机制不同。这些发现突出了所提出的BO框架在解决非线性力学问题中广泛的反设计挑战方面的潜力。

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引用次数: 0

Developing artificial mechanics intuitions from extremely small data 从极小的数据中开发人工力学直觉

IF 4.3 3区工程技术 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY

Extreme Mechanics Letters

Pub Date : 2025-06-09 DOI: 10.1016/j.eml.2025.102371

Jingruo Peng, Shuze Zhu

Humans can possess good mechanics intuitions by learning from a few examples, which leads to the question of how to develop artificial mechanics intuitions that can be learned from small data, as we are eagerly entering the era of artificial intelligence. We propose in this Letter the sample-switchable training method, which successfully develops highly-accurate artificial mechanics intuitions that can master brachistochrone problem, catenary problem, and large nonlinear deformation problem of elastic plate by learning from no more than three samples. The model’s intuitive prediction ability increases nonlinearly with respect to the number of training samples, suggesting that superb mechanics intuitions can be in principle achieved based on a finite number of samples, reflecting how human brains form good mechanics intuitions just by learning a few cases. Our current work presents an alternative perspective for educating artificial intelligence capable of intuitively understanding and predicting how materials deform and move, a scenario that has been frequently seen in Science-Fiction movies.

人类可以通过几个例子的学习来拥有良好的力学直觉，这就引出了一个问题，当我们急切地进入人工智能时代的时候，如何开发出可以从小数据中学习的人工力学直觉。我们在这篇论文中提出了样本切换训练方法，该方法通过不超过三个样本的学习，成功开发出高精度的人工力学直觉，可以掌握弹性板的臂链线问题、悬链线问题和大非线性变形问题。该模型的直观预测能力随着训练样本数量的增加呈非线性增长，说明在有限的样本数量上原则上可以实现极好的力学直觉，反映了人类大脑是如何通过学习几个案例形成良好的力学直觉的。我们目前的工作为教育人工智能提供了另一种视角，能够直观地理解和预测材料如何变形和移动，这是科幻电影中经常出现的场景。

引用次数: 0

Micro-ballistic impact of a Co33Os20Ta10B37 metallic glass with ultrahigh dynamic strength 超高动强度Co33Os20Ta10B37金属玻璃的微弹道冲击

IF 4.3 3区工程技术 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY

Extreme Mechanics Letters

Pub Date : 2025-06-09 DOI: 10.1016/j.eml.2025.102372

G. Ding , H.B. Zhao , X.H. Jing , X.M. Duan , S.L. Cai , H.B. Zhou , L. Yu , G.H. Duan , J. Duan , R. Li , L.H. Dai , M.Q. Jiang

Metallic glasses (MGs) show significant potential for hypervelocity impact protection due to their high hardness and dynamic strength. In this study, the protective performance of a new Co₃₃Os₂₀Ta₁₀B₃₇ MG was systematically evaluated. Plate impact experiments revealed an ultra-high Hugoniot elastic limit (HEL) up to 19 GPa, setting a new record for metallic materials. Using the laser-induced micro-particle impact test (LIPIT), we characterized the impact response and protective performance of Co₃₃Os₂₀Ta₁₀B₃₇ subjected to SiO₂ micro-particle impact. The results demonstrated a high coefficient of restitution (COR) and dynamic strength for Co₃₃Os₂₀Ta₁₀B₃₇. More importantly, the low impact-mode ratio further indicates that it can efficiently withstand the high-velocity impact of micro-particles, as confirmed by the absence of craters in post-impact surface. These results emphasize the outstanding resistance of Co₃₃Os₂₀Ta₁₀B₃₇ MG to hypervelocity impact, underscoring its promising potential as an advanced protective material.

金属玻璃由于其高硬度和高动强度，在超高速冲击防护方面显示出巨大的潜力。本研究对新型Co33Os20Ta10B37 MG的防护性能进行了系统评价。平板撞击实验显示，超高Hugoniot弹性极限（HEL）高达19 GPa，创下了金属材料的新纪录。采用激光诱导微颗粒冲击试验（LIPIT），表征了Co33Os20Ta10B37在SiO2微颗粒冲击下的冲击响应和防护性能。结果表明，Co33Os20Ta10B37具有较高的恢复系数（COR）和动态强度。更重要的是，低的撞击模态比进一步表明它可以有效地承受微粒的高速撞击，这一点从撞击后表面没有陨石坑得到了证实。这些结果强调了Co33Os20Ta10B37 MG对超高速撞击的卓越抗性，强调了其作为先进防护材料的潜力。

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引用次数: 0

Data-driven scheme for two-scale chemo-mechanical coupled problem for heterogeneous materials under transient chemical diffusion 非均质材料瞬态化学扩散双尺度化学-力学耦合问题的数据驱动格式

IF 4.3 3区工程技术 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY

Extreme Mechanics Letters

Pub Date : 2025-06-04 DOI: 10.1016/j.eml.2025.102363

Xinwei Yang , Chunwang He , Jie Yang , Yikun Wu , Le Yang , Hao-Sen Chen

This study developed a data-driven computational scheme of multiscale multiphysics coupled problem for heterogeneous materials under transient chemical diffusion. Firstly, the data-driven scheme decouples the multiscale problem into two stages, i.e., offline generation of material constitutive behavior database by microscopic simulation, and online macroscopic boundary value problem (BVP) based on the data-driven mechanical scheme. In addition, data-driven scheme converts the multiphysics coupled constitutive relationship into the material conjugate quantities in database which avoids the poor convergence in multiscale multiphysics coupled calculation. Then, a two-scale chemo-mechanical model with a simple microstructure is validated in two cases: diffusion-induced mechanical deformation and deformation-enhanced chemical diffusion. The results show that the proposed framework can characterize the chemo-mechanical coupled behavior with good convergence and accuracy, which is more efficient than the full-scale finite element simulation. Finally, this data-driven scheme is applied to analyze the multilayer porosity structures for lithium-ion battery cathodes. The results show that cathodes with gradient porosity design can improve the utilization of active materials and enhance the effective capacity.

本文提出了非均质材料瞬态化学扩散下多尺度多物理场耦合问题的数据驱动计算方案。首先，数据驱动方案将多尺度问题解耦为两个阶段，即通过微观模拟离线生成材料本构行为数据库，以及基于数据驱动力学方案的在线宏观边值问题。此外，数据驱动方案将多物理场耦合本构关系转换为数据库中的材料共轭量，避免了多尺度多物理场耦合计算收敛性差的问题。然后，在扩散引起的机械变形和变形增强的化学扩散两种情况下，验证了具有简单微观结构的双尺度化学-力学模型。结果表明，该框架能较好地表征化学-力学耦合行为，具有较好的收敛性和精度，比全尺寸有限元模拟更有效。最后，将该数据驱动方案应用于锂离子电池阴极的多层孔隙结构分析。结果表明，采用梯度孔隙度设计的阴极可以提高活性物质的利用率，提高阴极的有效容量。

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引用次数: 0