Extreme Mechanics Letters最新文献_第10页

3D-printed silica glass micro-mechanical device (MMD) for in situ mechanical testing 用于现场机械测试的3d打印硅玻璃微机械装置（MMD）

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

Extreme Mechanics Letters

Pub Date : 2025-08-01 Epub Date: 2025-07-10 DOI: 10.1016/j.eml.2025.102384

Ziyong Li , Yanwen Jia , Fang Su , Juzheng Chen , Xiewen Wen , Wenjun Liang , Hao Wu , Yang Lu

Micro-electro-mechanical systems (MEMS)-based devices offers a premium solution for versatile in situ micro-/nano- mechanical characterizations of low-dimensional materials, however, they are primarily manufactured using costly top-down silicon photolithography microfabrication processes. Previously, we demonstrated that high-resolution bottom-up 3D printing technologies can be used for printing such micro-mechanical device (MMD), but those photopolymer-based devices are of low-modulus and less stable for long-term use. Here, based on our recently developed high-resolution glass 3D printing technique, we show that silica glass MMD with high definition and performance. The versatility of high-resolution additive manufacturing, combined with the long-term mechanical stability as well as exceptional mechanical properties of high-performance glass, enables the fabrication of MMDs with more desirable characteristics. This facilitates the in-situ micro-/nano- mechanical characterizations on novel materials. The tensile behaviors of microfibers and nanofilms, as demonstrated by our developed MMDs, showcase the potential for a groundbreaking approach to in situ micro-/nano- mechanical testing through the integration of 3D printing, high-performance glass, and MEMS technologies.

基于微机电系统（MEMS）的器件为低维材料的多用途原位微/纳米机械表征提供了一种优质的解决方案，然而，它们主要是使用昂贵的自上而下硅光刻微加工工艺制造的。此前，我们证明了高分辨率自下而上的3D打印技术可用于打印此类微机械设备（MMD），但这些基于光聚合物的设备具有低模量且长期使用不太稳定。在这里，基于我们最近开发的高分辨率玻璃3D打印技术，我们展示了具有高清晰度和高性能的二氧化硅玻璃MMD。高分辨率增材制造的多功能性，加上高性能玻璃的长期机械稳定性和卓越的机械性能，使mmd的制造具有更理想的特性。这有助于对新材料进行原位微/纳米力学表征。正如我们开发的mmd所展示的那样，微纤维和纳米膜的拉伸行为展示了通过3D打印、高性能玻璃和MEMS技术的集成，为原位微/纳米机械测试提供开创性方法的潜力。

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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 : 2025-08-01 Epub 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

A novel mechanical criterion and interpretation for dual stress plateau phenomenon in NiTi alloy under tension 张力作用下NiTi合金双应力平台现象的新力学判据及解释

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

Extreme Mechanics Letters

Pub Date : 2025-08-01 Epub Date: 2025-07-07 DOI: 10.1016/j.eml.2025.102380

Xi Qie, Jianping Lin

Numerous studies have investigated Lüders band and transformation stress plateau in NiTi. However, localized plastic deformation (LPD) of martensite and the stress drop before the second stress plateau remain poorly understood. In this study, drawing an analogy to Lüders band propagation, we observed LPD band nucleation propagation in a microstructure with 253 nm grain size by in-situ Digital Image Correlation (DIC). Based on displacement conservation, we propose a mechanical criterion for inelastic loading in NiTi. This criterion accurately predicts the stress drop associated with LPD band nucleation and movement, providing a theoretical foundation. Furthermore, we systematically explain, for the first time, the abnormal strain softening effect responsible for the second stress plateau during martensitic plastic deformation. By offering new insights into martensitic transformation and LPD mechanisms, this research advances the understanding of dual stress plateaus and LPD in NiTi.

大量研究对镍钛中的 ders带和相变应力平台进行了研究。然而，马氏体的局部塑性变形（LPD）和第二次应力平台前的应力降仍不清楚。在本研究中，我们通过原位数字图像相关（DIC）技术，类比LPD波段的传播，观察了253 nm晶粒尺寸的微观结构中LPD波段的形核传播。在位移守恒的基础上，提出了NiTi非弹性载荷的力学判据。该判据准确预测了与LPD带形核和运动相关的应力降，为LPD带形核和运动提供了理论依据。此外，我们首次系统地解释了马氏体塑性变形过程中导致第二次应力平台的异常应变软化效应。通过对马氏体相变和LPD机制的新认识，本研究推进了对NiTi双应力平台和LPD的认识。

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 : 2025-08-01 Epub 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

Water-abundant and tough structured composite hydrogels via ion transfer printing 通过离子转移印花制备的水凝胶

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

Extreme Mechanics Letters

Pub Date : 2025-08-01 Epub Date: 2025-05-30 DOI: 10.1016/j.eml.2025.102367

Jingping Wu, Zhengjin Wang, Xiao Liu, Yong Zheng, Yang Gao, Jian Hu

Hydrogels with high water content and toughness are essential to various applications in smart materials and biomimetic systems. However, there exists a conflict between water content and toughness. To enhance toughness, high polymer chain density or water-free reinforcements are usually introduced into hydrogel matrices, which inevitably lead to a reduction in water content. In this study, we present a facile method for preparing water-abundant and tough hydrogels through ion transfer printing. By utilizing sodium alginate/polyacrylamide (Alg/PAAm) hydrogels as a flexible matrix and Fe³⁺ ions as stiffening agents, we selectively introduce Fe³⁺ ions into predefined regions of the hydrogel matrix, resulting in well-structured composite hydrogels comprising soft Alg/PAAm matrix and hard Fe³⁺-crosslinked Alg/PAAm (Fe-Alg/PAAm) fibers. As both the matrix and fibers are stretchable and water-abundant, the composites exhibit impressive stretchability (ε∼1000 %) and water content (p∼95 %). Notably, the alternating arrangement of the soft and hard fiber/matrix architecture effectively prevents crack propagation during loading by inducing stress deconcentration at the crack tip, thereby leading to exceptional toughness (Γ∼22000 J/m²). This simple method introduces a universal design strategy for constructing stretchable, water-abundant, and tough hydrogels, considering that ionic crosslinking with multi-valent cation crosslinkers is widely used in hydrogels. Beyond the Fe³⁺ and Alg/PAAm hydrogel system discussed here, this concept can be extended to various combinations of multi-valent ions and hydrogel networks containing opposite charges.

具有高含水量和韧性的水凝胶在智能材料和仿生系统的各种应用中是必不可少的。但其含水量与韧性之间存在矛盾。为了增强韧性，通常在水凝胶基质中引入高聚物链密度或无水增强剂，这不可避免地导致含水量的降低。在这项研究中，我们提出了一种简单的方法，通过离子转移印刷制备富水和坚韧的水凝胶。利用海藻酸钠/聚丙烯酰胺（Alg/PAAm）水凝胶作为柔性基质，Fe3+离子作为增强剂，我们选择性地将Fe3+离子引入水凝胶基质的预定区域，得到结构良好的复合水凝胶，包括软Alg/PAAm基质和硬Fe3+交联Alg/PAAm （Fe-Alg/PAAm）纤维。由于基体和纤维都具有可拉伸性和丰富的水分，复合材料表现出令人印象深刻的拉伸性（ε ~ 1000 %）和含水量（p ~ 95 %）。值得注意的是，软硬纤维/基体结构的交替排列通过诱导裂纹尖端的应力分散，有效地防止了加载过程中的裂纹扩展，从而获得了优异的韧性（Γ ~ 22000 J/m2）。考虑到离子交联与多价阳离子交联剂在水凝胶中的广泛应用，这种简单的方法为构建可拉伸、富水和坚韧的水凝胶提供了一种通用的设计策略。除了这里讨论的Fe3+和Alg/PAAm水凝胶体系之外，这个概念还可以扩展到各种多价离子的组合和含有相反电荷的水凝胶网络。

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引用次数: 0

Front cover CO1 前盖CO1

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

Extreme Mechanics Letters

Pub Date : 2025-08-01 Epub Date: 2025-07-16 DOI: 10.1016/S2352-4316(25)00099-9

引用次数: 0

The mapping relationship between initiator and mechanical properties of free radical polymerized hydrogels 自由基聚合水凝胶引发剂与力学性能的映射关系

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

Extreme Mechanics Letters

Pub Date : 2025-06-01 Epub Date: 2025-04-08 DOI: 10.1016/j.eml.2025.102327

Yujun Guo , Heng Zhu , Zhe Chen , Shaoxing Qu

Most of the hydrogels are formed by free radical polymerization of the precursor solution containing monomer, crosslinker, initiator, and water. The change of any one of the components will affect the final network structure, which will lead to different mechanical properties. Although the initiator plays a key role in the synthesis of hydrogels, the mapping relationship between the initiator and the mechanical properties of hydrogels has not been well explained. In this paper, a polyacrylamide hydrogel with high water content is taken as the research object. The influence of the initiator on the elastic modulus and toughness of the hydrogel is analyzed experimentally and theoretically. In theory, we reveal the microscopic mechanism of the initiator on the evolution of the network structure. By taking the kinetic chain length as an intermediate variable, a mechanochemical coupling model is developed to predict the relationship between the initiator and the elastic modulus. The theoretical predictions agree well with the experimental results. Furthermore, we find that initiators can tune the modulus of hydrogels, but have little effect on toughness. These mechanical changes induced by initiators provide more options for hydrogel applications. And utilizing the kinetic chain length as a characteristic parameter for the evolution of the network helps elucidate the impact of free radical polymerization reactions on macroscopic mechanical behavior.

大多数水凝胶都是通过自由基聚合含有单体、交联剂、引发剂和水的前体溶液形成的。任何一种成分的改变都会影响最终的网络结构，从而导致不同的机械性能。虽然引发剂在水凝胶的合成中起着关键作用，但引发剂与水凝胶机械性能之间的映射关系尚未得到很好的解释。本文以一种高含水量的聚丙烯酰胺水凝胶为研究对象。实验和理论分析了引发剂对水凝胶弹性模量和韧性的影响。在理论上，我们揭示了引发剂对网络结构演变的微观机理。通过将动力学链长作为中间变量，建立了一个机械化学耦合模型来预测引发剂与弹性模量之间的关系。理论预测与实验结果非常吻合。此外，我们还发现引发剂可以调节水凝胶的模量，但对韧性的影响很小。引发剂引起的这些机械变化为水凝胶的应用提供了更多选择。利用动力学链长作为网络演变的特征参数，有助于阐明自由基聚合反应对宏观机械行为的影响。

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引用次数: 0

Layer-jamming soft gripper for improved stiffness control and underwater adhesion 层卡软夹具，改善刚度控制和水下附着力

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

Extreme Mechanics Letters

Pub Date : 2025-06-01 Epub Date: 2025-04-05 DOI: 10.1016/j.eml.2025.102322

Minseong Kim, Junyeock Oh, Donghoon Son

Soft robotic grippers have attracted significant attention due to their lightweight, simple structures, and versatile applications. Especially, soft suction cups (SSCs) are generally used for their low energy consumption and a high lifting ratio. However, they encounter challenges for mitigating a trade-off between conformability and adhesion performance and applications for the wet conditions. This paper introduces the layer-jamming soft gripper (LJSG), a novel design that significantly enhances adhesion while maintaining adaptive conformability and demonstrates effective underwater adhesion. Notably, the LJSG is resistant to hydraulic leakage due to a protective membrane attached to its body. Additionally, our design concurrently enhances adhesion capability with layer-jamming mechanism compared to conventional SSCs and mitigates the impact of unjammed layers on conformability by incorporating an interval to reduce required preload for interfacial adaptation. These features collectively enable the LJSG to demonstrate reliable performance in grasping diverse objects underwater. We elucidate the layer-jamming mechanism and demonstrate how jammed layers enhance maximum pull-off force by analytical method, numerical method, and experiments. The LJSG shows 300 % adhesion improvement than previous SSCs via the experiments, while 290 % from the analytical method and 245 % from the numerical method. The experiments also demonstrate that LJSG has an enhanced capability for gripping curved objects. This design can be applicable for grasping objects regardless of their curvatures and sizes. Hence, these findings underscore LJSG’s potential for diverse applications, particularly in challenging underwater environments, and position it as a viable solution for adaptive, high-performance soft robotic adhesion.

机器人软爪以其重量轻、结构简单、用途广泛而备受关注。特别是软吸盘（ssc）由于其低能耗和高提升比而被广泛使用。然而，它们面临的挑战是如何减轻相容性和粘附性能之间的权衡，以及在潮湿条件下的应用。本文介绍了一种新颖的层卡软夹持器（LJSG），它在保持自适应顺应性的同时显著增强了附着力，并展示了有效的水下附着力。值得注意的是，LJSG具有抗液压泄漏的能力，因为它的身体上附着了一层保护膜。此外，与传统ssc相比，我们的设计同时增强了层卡机制的粘附能力，并通过加入间隔来减少界面适应所需的预载荷，减轻了未卡层对相容性的影响。这些特点共同使LJSG在水下捕捉各种物体时表现出可靠的性能。通过解析法、数值法和实验，阐明了层间的干扰机制，并论证了被干扰的层间如何提高最大拉脱力。实验结果表明，LJSG的粘接性能比以往的ssc提高了300 %，比解析法提高了290 %，比数值法提高了245 %。实验还表明，LJSG对弯曲物体的抓取能力有所提高。这种设计可以适用于抓取物体，无论其曲率和大小。因此，这些发现强调了LJSG的多种应用潜力，特别是在具有挑战性的水下环境中，并将其定位为自适应、高性能软机器人粘附的可行解决方案。

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引用次数: 0

Multi-scale investigation of orientation-dependent mechanical properties and fracture propagation in cortical bone using digital volume correlation and atomic force microscopy 使用数字体积相关和原子力显微镜对皮质骨的定向相关力学性能和骨折扩展进行多尺度研究

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

Extreme Mechanics Letters

Pub Date : 2025-06-01 Epub Date: 2025-04-18 DOI: 10.1016/j.eml.2025.102338

Hutomo Tanoto , Hanwen Fan , Anoushka Prabhu , Fernanda Espinoza , Yuxiao Zhou

This study investigates the orientation-dependent mechanical properties and fracture propagation behavior in bovine cortical bone, focusing on the role of lamellar plane orientation and its internal hierarchical structures—both of which are critical to bone mechanical strength and fracture resistance. By combining mechanical testing, micro-computed tomography (micro-CT), digital volume correlation (DVC), and atomic force microscopy (AFM), we examined region- and orentation-dependent mechanical properties of cortical bone, as well as the crack propagation influenced by underlying microstructures. At sub-millimeter scale, three-dimensional (3D) displacement and strain captured through in situ three-point bending and DVC provided detailed insights into internal deformation patterns during crack propagation. Distinct crack propagation behaviors were observed in bone samples with lamellar planes oriented parallel and perpendicular to the loading plane. AFM nanomechanical mapping was performed on cracked cross-sections, revealing the heterogeneous mechanical properties within the hierarchical lamellar structure. These micrometer-scale measurements, obtained from orthogonal cracked cross-sections, help explain the different crack propagation mechanisms observed during the bending experiments. Our findings demonstrate that the orientation of lamellar plane— the fundamental structural component of both plexiform and osteonal bone—relative to the loading plane plays a critical role in determining crack paths and local strain distribution. The integrated application of DVC and AFM provides a multiscale perspective on fracture resistance in cortical bone. These insights have important implications for the design of biomimetic materials in bone implants and for improving clinical assessments of fracture risk.

本研究研究了牛皮质骨的取向相关力学性能和骨折扩展行为，重点研究了板层平面取向及其内部层次结构的作用，这两者对骨的机械强度和抗骨折性至关重要。通过结合力学测试、微计算机断层扫描（micro-CT）、数字体积相关（DVC）和原子力显微镜（AFM），我们研究了皮质骨的区域和方向相关的力学特性，以及受底层微观结构影响的裂纹扩展。在亚毫米尺度下，通过原位三点弯曲和DVC捕获三维位移和应变，可以详细了解裂纹扩展过程中的内部变形模式。在与加载面平行和垂直的层状面方向下，骨试样的裂纹扩展行为明显。对裂纹截面进行了AFM纳米力学映射，揭示了分层层状结构内的非均匀力学性能。这些微米尺度的测量结果来自正交裂纹截面，有助于解释弯曲实验中观察到的不同裂纹扩展机制。我们的研究结果表明，层状面相对于加载面的取向在决定裂纹路径和局部应变分布方面起着关键作用。层状面是丛状和骨状骨的基本结构成分。DVC和AFM的综合应用为皮质骨的骨折抵抗提供了一个多尺度的视角。这些见解对骨植入物仿生材料的设计和改善骨折风险的临床评估具有重要意义。

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引用次数: 0

A method for identifying the damage thresholds of porcine brain under low- and medium-strain rates 中低应变率下猪脑损伤阈值的识别方法

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

Extreme Mechanics Letters

Pub Date : 2025-06-01 Epub Date: 2025-04-15 DOI: 10.1016/j.eml.2025.102335

Zhihui Qu , Yimou Fu , Qiuping Yang , Jingyu Wang , Liqun Tang , Shaoxing Qu

Predicting the damage thresholds of brain tissue is crucial for preventing permanent pathological changes and developing therapeutic interventions. This study presents a method for determining the damage thresholds of porcine brain tissue using experimental data and theoretical modeling. By conducting loading and unloading experiments on porcine brain samples, the mechanical responses under varying strain rates and maximum compressive strains are analyzed. A constitutive model incorporating viscoelastic behavior, the Mullins effect, and residual deformation is proposed, effectively characterizing the mechanical properties of the brain tissue. By calculating the ratio of damage-induced dissipated energy and viscoelastic dissipated energy, the extent of damage under different maximum compression strain is quantified. The method’s reliability is validated through examining changes in modulus between the stress–strain curves obtained from the first and second loadings. At a strain rate of 0.3

s^{- 1}

, the mild damage strain threshold is estimated to be 0.2 – 0.3, while the moderate-to-severe damage threshold falls within 0.3 – 0.4, aligning closely with values reported in the literature. Additionally, the damage strain thresholds at 200

s^{- 1}

are consistent with those at 0.3

s^{- 1}

. The corresponding stress threshold at 200

s^{- 1}

ranges from 5.9 to 11.4 kPa for mild damage and from 11.4 to 22.8 kPa for moderate-to-severe damage. The findings of this study are expected to contribute to brain damage prediction.

预测脑组织损伤阈值对于预防永久性病理改变和制定治疗干预措施至关重要。本研究提出了一种利用实验数据和理论模型确定猪脑组织损伤阈值的方法。通过对猪脑试样进行加载和卸载实验，分析了不同应变速率和最大压缩应变下的力学响应。提出了一种结合粘弹性行为、Mullins效应和残余变形的本构模型，有效地表征了脑组织的力学特性。通过计算损伤耗散能与粘弹性耗散能的比值，量化了不同最大压缩应变下的损伤程度。通过第一次和第二次加载得到的应力-应变曲线的模量变化，验证了该方法的可靠性。在应变速率为0.3s−1时，估计轻度损伤应变阈值为0.2 - 0.3，而中度至重度损伤阈值在0.3 - 0.4之间，与文献报道的值密切一致。200s−1时的损伤应变阈值与0.3s−1时的损伤应变阈值一致。200s−1的应力阈值范围为：轻度损伤为5.9 ~ 11.4 kPa，中度至重度损伤为11.4 ~ 22.8 kPa。这项研究的结果有望有助于预测脑损伤。

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引用次数: 0