European Journal of Mechanics A-Solids最新文献_第2页

Fracture behaviour of notched P3HB specimens – Effects of strain rate and natural aging 缺口P3HB试样的断裂行为。应变速率和自然时效的影响

IF 4.2 2区工程技术 Q1 MECHANICS

European Journal of Mechanics A-Solids

Pub Date : 2026-01-22 DOI: 10.1016/j.euromechsol.2026.106036

Elżbieta Bura , Wiesław Frącz

This study investigates the fracture mechanics of notched P3HB specimens subjected to monotonic tensile loading under different average strain rates, from 0.14·10⁻³ s⁻¹ to 14·10⁻³ s⁻¹, and tested 24, 168, and 720 h after manufacturing to capture changes due to natural aging. Flat specimens were weakened with double-sided V-notches of various root radii to analyse stress concentration effects. Force response, elongation, and fracture surface morphology were examined to identify mechanisms governing crack initiation and propagation. Natural aging increased Young's modulus by 15–20 % and reduced elongation at break by 30–40 %, indicating embrittlement over time. In contrast, higher strain rates promoted up to 25 % greater maximum force and elongation to fracture, likely due to strain-induced mesophase formation. In all cases, fracture initiated at the notch root, with a larger notch radius reducing stress concentration and delaying crack initiation. A progressive shift toward brittle fracture behaviour was observed with aging duration and strain rate. The predictive capability of two classical brittle-fracture criteria-Maximum Tangential Stress (MTS) and Mean Stress (MS) – was evaluated. Significant discrepancies between predicted and experimental critical loads were found, with errors of approximately 49–56 %. These results demonstrate that existing criteria do not adequately capture local deformation mechanisms in P3HB. Reliable fracture prediction therefore requires models incorporating evolving plastic strain fields and experimentally derived hardening behaviour, providing a foundation for improved failure criteria for aging-sensitive polymers. When critical parameters were calibrated using experimental data within the Theory of Critical Distances framework, the prediction error was reduced to below 7 % (MTS), demonstrating that the proposed approach provides quantitative predictive capability for notched P3HB specimens across different aging times and strain rates.

在0.14·10−3 s−1到14·10−3 s−1的不同平均应变速率下，研究了有缺口的P3HB试样在单调拉伸载荷下的断裂力学，并在制造后24、168和720 h进行了测试，以捕捉自然时效引起的变化。采用不同根半径的双面v形切口对平面试件进行削弱，分析应力集中效应。力响应，伸长率和断裂表面形貌进行了检查，以确定控制裂纹萌生和扩展的机制。自然时效使杨氏模量增加了15 - 20%，断裂伸长率降低了30 - 40%，表明随着时间的推移脆化。相比之下，较高的应变率可使断裂的最大力和伸长率提高25%，这可能是由于应变诱导的中间相形成。在所有情况下，断裂都是从缺口根部开始的，较大的缺口半径减少了应力集中，延迟了裂纹的发生。随着时效时间和应变速率的增加，逐渐向脆性断裂行为转变。对最大切向应力（MTS）和平均应力（MS）两种经典脆性断裂准则的预测能力进行了评价。预测临界负荷与实验临界负荷之间存在显著差异，误差约为49% - 56%。这些结果表明，现有的标准不能充分捕捉P3HB的局部变形机制。因此，可靠的断裂预测需要结合不断变化的塑性应变场和实验导出的硬化行为的模型，为改进老化敏感聚合物的失效标准提供基础。当使用临界距离理论框架内的实验数据校准关键参数时，预测误差降至7% （MTS）以下，表明所提出的方法可以对不同时效时间和应变速率的缺口P3HB样品进行定量预测。

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引用次数: 0

Designing the futuristic dielectric elastomer minimum energy structures using artificial neural networks (ANN) 基于人工神经网络的未来电介质弹性体最小能量结构设计

IF 4.2 2区工程技术 Q1 MECHANICS

European Journal of Mechanics A-Solids

Pub Date : 2026-01-21 DOI: 10.1016/j.euromechsol.2026.106034

Bhaskar Anupam, Keshav Purviya, Ankur Miglani, Aman Khurana

Dielectric elastomer minimum energy structures (DEMES) have gained significant attention for their ability to switch between multiple equilibrium states. These structures are formed when a pre-stretched elastomer film adheres to an inextensible frame and achieves equilibrium through energy minimization. Traditional methods for analyzing DEMES mechanics-numerical, theoretical, and experimental are often labor-intensive and time-consuming. This paper introduces the application of artificial neural network (ANN) techniques to predict the behavior of DEMES-based actuators efficiently. Using the Levenberg–Marquardt and Bayesian Regularization algorithms, the performance of two prototypes: the four-arm gripper and the flapping-wing actuator previously studied experimentally and numerically in Khurana et al. (2024a), is predicted. The ANN-based approach demonstrates excellent agreement with the numerical results while significantly reducing computation time. This study highlights the potential of ANN techniques as a fast and reliable tool for the parametric evaluation of DEMES structures, streamlining the design and analysis process. Future applications of DEMES, enhanced by ANN-based predictive models, include the development of adaptive soft robotics, bio-inspired actuators, and energy-efficient morphing structures. These advancements could lead to intelligent material systems with real-time control capabilities for biomedical devices, aerospace engineering, and wearable technologies.

介电弹性体最小能量结构（DEMES）由于能够在多种平衡态之间切换而受到广泛关注。当预拉伸弹性体薄膜附着在不可扩展的框架上并通过能量最小化达到平衡时，这些结构就形成了。传统的分析DEMES力学的方法——数值的、理论的和实验的——往往是劳动密集型和耗时的。本文介绍了应用人工神经网络（ANN）技术有效地预测基于demes的执行器的行为。利用Levenberg-Marquardt和Bayesian正则化算法，预测了Khurana等人（2024a）先前通过实验和数值研究的两种原型：四臂抓手和扑翼驱动器的性能。基于人工神经网络的方法与数值结果吻合良好，同时大大减少了计算时间。这项研究强调了人工神经网络技术作为一种快速可靠的工具对DEMES结构进行参数评估的潜力，简化了设计和分析过程。基于人工神经网络的预测模型增强了DEMES的未来应用，包括自适应软机器人、仿生致动器和节能变形结构的开发。这些进步可能会导致具有实时控制能力的智能材料系统，用于生物医学设备、航空航天工程和可穿戴技术。

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引用次数: 0

Characterization of the soft behavior of nematic elastomers over a range of temperature and strain rates 向列弹性体在一定温度和应变速率下的软性能表征

IF 4.2 2区工程技术 Q1 MECHANICS

European Journal of Mechanics A-Solids

Pub Date : 2026-01-21 DOI: 10.1016/j.euromechsol.2026.106035

Alice Kutsyy , Adeline Wihardja , Victoria Lee , Kaushik Bhattacharya

Nematic elastomers are a particular class of liquid crystal elastomers (LCEs) that exhibit both liquid-crystalline order and rubber (entropic) elasticity. This combination makes them stimuli-responsive soft materials with a number of unusual thermo-mechanical properties. They have been proposed for various applications, including soft robotics, enhanced adhesion, and impact resistance. This paper presents a new experimental setup and a comprehensive dataset characterizing the soft behavior of nematic elastomers over a range of temperatures and strain rates. We also fit the results to a recently developed model of nematic elastomers (Lee et al., 2023).

向列弹性体是一类特殊的液晶弹性体（LCEs），它同时具有液晶有序和橡胶（熵）弹性。这种组合使它们成为具有许多不寻常的热机械性能的刺激响应软材料。它们已被提出用于各种应用，包括软机器人，增强附着力和抗冲击性。本文提出了一个新的实验装置和一个全面的数据集，表征了向列弹性体在一系列温度和应变速率下的软行为。我们还将结果拟合到最近开发的向列弹性体模型（Lee et al., 2023）。

引用次数: 0

Creep rupture life prediction model combining microstructure evolution and Monkman-Grant relation for thermal and irradiation creep 结合显微组织演化和Monkman-Grant关系的热、辐射蠕变断裂寿命预测模型

IF 4.2 2区工程技术 Q1 MECHANICS

European Journal of Mechanics A-Solids

Pub Date : 2026-01-20 DOI: 10.1016/j.euromechsol.2026.106033

Dong Tang , Shilin Li , Long Yu , Xinfu He , Xiazi Xiao

In this work, a creep rupture life prediction model is proposed by combining the creep constitutive laws and Monkman-Grant (M-G) relation to analyze the rupture time under thermal and irradiation creep. The model could simultaneously characterize the influence of testing temperature, applied stress and irradiation damage on the steady-state creep strain rate by taking into account corresponding microstructure evolution, accurately capture the mechanism transitions during creep, and then convert the steady-state creep strain rate into macroscopic rupture life via the M-G relation. Once the irradiation effect is ignored, the model can be degraded to predict the thermal creep rupture life. Model validation is achieved by comparing theoretical results with the experimental data of 15-15Ti, 316H, P92 and 304 steels for both thermal and irradiation creep. Related mechanism analyses indicate that the shortened thermal creep rupture life with increasing stress and temperature is mainly ascribed to the accelerated activity of dislocation climb that leads to the enhancement of dislocation mobility and acceleration of creep damage accumulation. Under irradiation creep, it is the elevated vacancy diffusion coefficient that leads to the enhanced activity of dislocation climb, and finally results in the shorter irradiation creep rupture life when compared with the one under thermal creep. The proposed model could provide an efficient theoretical tool for material creep life assessment under extreme environments.

本文结合蠕变本构律和Monkman-Grant （M-G）关系，建立了热、辐射蠕变作用下的蠕变断裂寿命预测模型。该模型能够同时表征试验温度、外加应力和辐照损伤对稳态蠕变应变速率的影响，并考虑相应的微观组织演变，准确捕捉蠕变过程中的机制转变，进而通过M-G关系将稳态蠕变应变速率转化为宏观断裂寿命。在忽略辐照效应的情况下，可以对模型进行退化以预测热蠕变断裂寿命。通过将理论结果与15-15Ti、316H、P92和304钢的热蠕变和辐照蠕变实验数据进行对比，验证了模型的有效性。相关机理分析表明，随着应力和温度的升高，热蠕变断裂寿命缩短的主要原因是位错爬升活动加快，导致位错迁移率增强，蠕变损伤积累加速。辐照蠕变下，空位扩散系数的升高导致位错攀爬活性增强，最终导致辐照蠕变断裂寿命较热蠕变短。该模型可为极端环境下材料蠕变寿命评估提供有效的理论工具。

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引用次数: 0

Analytical and numerical study of the radial compression of a helical spring: Relationship between diameter variation, elongation and radial force 螺旋弹簧径向压缩的解析与数值研究：直径变化、延伸率与径向力的关系

IF 4.2 2区工程技术 Q1 MECHANICS

European Journal of Mechanics A-Solids

Pub Date : 2026-01-20 DOI: 10.1016/j.euromechsol.2026.106026

Franck Jourdan

This study investigates the mechanical behavior of helical springs subjected to radial compression, a configuration particularly relevant to biomedical applications such as stents. Traditional models, notably those by Wahl and later Jedwab & Clerc (J&C), were developed for axial loading and rely on geometric assumptions that do not hold under radial compression—most notably, the constraint of non-rotating ends. These assumptions lead to significant overestimations of spring elongation. To address this limitation, an alternative analytical model is proposed, based on beam theory and Castigliano’s theorem. This model accounts for end rotation and spring coiling, and incorporates material properties such as Poisson’s ratio. The analytical predictions are validated through finite element simulations (FEM), showing strong agreement in elongation estimates and highlighting the limitations of J&C’s approach. Two numerical benchmark tests are conducted to compare the models: one varying the initial pitch angle, and another replicating J&C’s stent configuration. Results demonstrate that elongation and radial force are sensitive to pitch angle and that spring coiling significantly influences mechanical response. The alternative theory provides a more accurate and physically consistent framework for modeling radially compressed springs, with implications for the design of medical and industrial devices.

本研究调查了螺旋弹簧在径向压缩下的机械行为，这种结构与支架等生物医学应用特别相关。传统的模型，尤其是Wahl和后来的Jedwab &； Clerc （J&；C）的模型，是针对轴向载荷开发的，并且依赖于在径向压缩下不成立的几何假设——最明显的是，非旋转端部的约束。这些假设导致了对弹簧伸长的严重高估。为了解决这一限制，提出了一种基于梁理论和卡斯蒂利亚诺定理的替代解析模型。该模型考虑了端部旋转和弹簧卷曲，并结合了材料特性，如泊松比。通过有限元模拟（FEM）验证了分析预测，在伸长率估计上显示出强烈的一致性，并突出了强生公司方法的局限性。进行了两个数值基准试验来比较模型：一个是改变初始俯仰角的模型，另一个是复制强生支架结构的模型。结果表明，伸长率和径向力对俯仰角敏感，弹簧卷取对机械响应有显著影响。替代理论为径向压缩弹簧的建模提供了一个更准确和物理上一致的框架，对医疗和工业设备的设计具有指导意义。

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引用次数: 0

Ultrahigh strain rate compression and tensile fracture in polyimide and polyimide-based composites: A comparative study 聚酰亚胺与聚酰亚胺基复合材料超高应变率压缩拉伸断裂的比较研究

IF 4.2 2区工程技术 Q1 MECHANICS

European Journal of Mechanics A-Solids

Pub Date : 2026-01-20 DOI: 10.1016/j.euromechsol.2026.106031

Y.X. Zhao , Y. Cai , R.C. Pan , N.B. Zhang , Tao Liu , K. Li , L. Lu , S.N. Luo

Plate impact experiments are conducted on pure polyimide, a 15% graphite filled polyimide composite, and a 15% graphite/10% polytetrafluoroethylene (PTFE) filled polyimide composite, to investigate their compression and spall damage under ultrahigh strain rate loading. The Hugoniot equation of state (shock adiabat) of polyimide is measured up to a peak shock stress of 1.6 GPa with the reverse-impact method. Free-surface velocity histories of polyimide/polyimide composites are measured to deduce their dynamic mechanical properties, including spall strength, interfacial strength, and tensile strain rate. The addition of graphite leads to sequential interfacial debonding and matrix fracture. The graphite/matrix interface tensile strength is approximately 0.05 GPa for the two composites. Spall strength shows negligible dependence on impact velocity for the three materials studied. X-ray computed tomography is conducted on both pre- and post-impact samples. Compared to pure polyimide, the fracture surfaces of the graphite-filled polyimide composite exhibit increased roughness; the debonding at the graphite-polyimide interfaces provides numerous void nucleation sites, results in a more discrete damage distribution, but delays the fracture of the matrix. The incorporation of PTFE reduces matrix integrity, leading to more significant spall damage and a reduction in spall strength. Our present findings not only enhance the understanding of damage mechanisms in graphite-filled polyimide composites, but also provide valuable guidance for the application of polymer composites in protective and structural materials.

对纯聚酰亚胺、15%石墨填充聚酰亚胺复合材料和15%石墨/10%聚四氟乙烯（PTFE）填充聚酰亚胺复合材料进行了平板冲击实验，研究了它们在超高应变率载荷下的压缩和剥落损伤。用反向冲击法测量了峰值冲击应力为1.6 GPa时聚酰亚胺的Hugoniot状态方程（冲击绝热）。测量了聚酰亚胺/聚酰亚胺复合材料的自由表面速度历史，以推断其动态力学性能，包括剥落强度、界面强度和拉伸应变率。石墨的加入导致了连续的界面剥离和基体断裂。两种复合材料的石墨/基体界面抗拉强度约为0.05 GPa。所研究的三种材料的剥落强度与冲击速度的关系可以忽略不计。对撞击前后的样品进行了x射线计算机断层扫描。与纯聚酰亚胺相比，石墨填充聚酰亚胺复合材料的断口表面粗糙度增加；石墨-聚酰亚胺界面的脱粘提供了大量的空穴成核位点，导致更离散的损伤分布，但延迟了基体的断裂。PTFE的掺入降低了基体的完整性，导致更显著的剥落损伤和剥落强度的降低。本研究结果不仅提高了对石墨填充聚酰亚胺复合材料损伤机理的认识，而且为聚合物复合材料在防护材料和结构材料中的应用提供了有价值的指导。

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引用次数: 0

Crack morphology effects on post-fracture tensile behavior of ionomer-laminated glass 裂纹形态对离子夹层玻璃断裂后拉伸性能的影响

IF 4.2 2区工程技术 Q1 MECHANICS

European Journal of Mechanics A-Solids

Pub Date : 2026-01-16 DOI: 10.1016/j.euromechsol.2026.106024

Dongdong Xie , Xing-Er Wang , Jian Yang , Yige Wang , Zhufeng Pan , Chenjun Zhao , Shennan Peng

The tensile behavior of fractured laminated glass, which is affected by crack morphology, is crucial for assessing its residual structural performance. This paper investigated the random-cracked tensile behavior of fractured SG (SentryGlas®) laminated glass with different tempering levels and glass thicknesses for the first time. Besides, the crack morphological features including fragment density and uniform parameter were captured. The uniform parameter was defined as the ratio of the minimum centroid distance of fragments to the assumed uniform centroid distance. It is shown that the equivalent stiffness and strength decrease with an increasing tempering level. The mechanical properties show a strong correlation with fragment density, whereas the uniform parameter has an insignificant correlation. It is followed by developing mesoscale numerical models considering the random crack morphology and effective adhesion of fragments. The numerical models provide a novel method for reproducing the realistic tensile behaviors of fractured laminated glass. The effective adhesion coefficient was determined and found to have a linear relationship with fragment density. The effects of tempering level, glass thickness, and SG thickness on the tensile behavior were parametrically analyzed. Furthermore, surrogate models were constructed to assess the equivalent stiffness and strength of fractured laminated glass with different design variables, providing effective approaches for post-fracture performance evaluation for the refined design under static loading and at room temperature.

断裂夹层玻璃的拉伸性能受裂纹形态的影响，是评价夹层玻璃残余结构性能的关键。本文首次研究了不同钢化水平和玻璃厚度的SG （sentryglass®）夹层玻璃断裂后的随机开裂拉伸行为。此外，还捕获了裂纹的形态特征，包括碎片密度和均匀参数。均匀参数定义为碎片的最小质心距离与假设的均匀质心距离之比。结果表明，等效刚度和强度随回火水平的增加而减小。力学性能与破片密度有较强的相关性，而均匀参数的相关性不显著。随后，建立了考虑随机裂纹形态和碎片有效粘附的中尺度数值模型。该数值模型为再现夹层玻璃断裂的真实拉伸行为提供了一种新的方法。测定了有效粘附系数，发现有效粘附系数与破片密度呈线性关系。参数化分析了回火水平、玻璃厚度和SG厚度对拉伸性能的影响。通过构建代理模型，对不同设计变量下夹层玻璃的等效刚度和强度进行评估，为静载和室温下的精细化设计提供了有效的断裂后性能评估方法。

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引用次数: 0

Mechanical behaviour of an optimised novel Ti6Al4V lattice structure fabricated via LPBF: “An experimental and FEA investigation” LPBF制备的新型优化Ti6Al4V晶格结构的力学行为：“实验和有限元研究”

IF 4.2 2区工程技术 Q1 MECHANICS

European Journal of Mechanics A-Solids

Pub Date : 2026-01-14 DOI: 10.1016/j.euromechsol.2026.106017

Kirandeep Singh , Guofang Liang , Kevin Tetsworth , Justin Cooper-White , Deniz U. Erbulut , Mingxing Zhang

Critical-sized bone defects lack the inherent capacity for self-repair and require engineered bone scaffold structures to provide mechanical stability while facilitating osteointegration. Conventional lattice architectures often fail to reconcile high strength with elevated porosity due to discontinuous geometries and stress concentrations at nodal junctions. The Hexanoid (HH) scaffold, inspired by curved surfaces and exhibiting three-dimensional periodicity, has demonstrated superior in-silico cell proliferation but remains mechanically suboptimal. This study introduces a titanium-based Modified Hexanoid (MH) scaffold, engineered to enhance structural performance while retaining porosity conductive to bone ingrowth. Scaffolds were fabricated using Ti6Al4V alloy via Laser Powder Bed Fusion (L-PBF) and mechanically benchmarked against HH, Cubic (CU) and Circular (CR) scaffold structures. Quasi-static compression testing reveals that the MH scaffold achieved an elastic modulus of ∼9 GPa, a yield strength of ∼104 MPa, and a compressive strength of ∼154 MPa, representing improvements of 24 %, 58 %, and 37 %, respectively, over the HH design. The MH design maintained a porosity of approximately 73 %, exceeding HH (∼61 %) and being comparable to CU (∼77 %) and CR (∼76 %). By combining porosity similar to that of trabecular bone with mechanical properties approaching those of cortical bone, the MH scaffold overcomes the strength-porosity trade-off, demonstrating strong potential for load-bearing orthopaedic implants.

临界尺寸的骨缺损缺乏固有的自我修复能力，需要工程骨支架结构在促进骨整合的同时提供机械稳定性。由于几何形状不连续和节点处的应力集中，传统的晶格结构往往无法调和高强度和高孔隙率。受曲面启发，具有三维周期性的Hexanoid （HH）支架显示出优越的硅细胞增殖能力，但机械性能仍不理想。本研究介绍了一种基于钛的改性类己烷支架（MH），旨在提高结构性能，同时保持有利于骨长入的孔隙度。支架采用Ti6Al4V合金通过激光粉末床熔合（L-PBF）制造，并以HH、Cubic （CU）和Circular （CR）支架结构为机械基准。准静态压缩测试表明，MH支架的弹性模量为~ 9 GPa，屈服强度为~ 104 MPa，抗压强度为~ 154 MPa，分别比HH设计提高了24%，58%和37%。MH设计保持了约73%的孔隙度，超过HH(~ 61%)，与CU（~ 77%）和CR（~ 76%）相当。通过结合类似小梁骨的孔隙度和接近皮质骨的力学性能，MH支架克服了强度-孔隙度的权衡，显示出承重骨科植入物的强大潜力。

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引用次数: 0

Phase-field modeling of fatigue-induced crack propagation in strain-hardening elastomers 应变硬化弹性体疲劳裂纹扩展的相场模拟

IF 4.2 2区工程技术 Q1 MECHANICS

European Journal of Mechanics A-Solids

Pub Date : 2026-01-14 DOI: 10.1016/j.euromechsol.2026.106030

Shreeraman Swamynathan , Sebastian Jobst , Marc-André Keip

Engineering materials and structures are often subject to repeated and cyclic loading during the entire life of a product. Prediction of fatigue failure under such loads has been a topic of interest in the scientific community for decades. In the context of the computational modeling of fracturing, the phase-field method has attracted great attention in the last years owing to its elegant way of modeling cracks within a continuum in the form of a scalar damage field. There is also growing literature where enhancements have been proposed to numerically model fatigue effects within the phase-field framework. However, most of the existing work concentrates on elastic and elasto-plastic behavior of metallic materials within the realm of small deformations. Fatigue formulations for polymers are also largely limited to Neo–Hookean models. In the present work, we propose a modeling framework that can be applied to the numerical simulation of fatigue crack growth of strain-hardening elastomeric materials, where the inextensibility of the polymeric chains is incorporated using a Gent-like material model. Numerical studies with increasing complexities are systematically performed to exemplify the striking features of the model. In addition, Wöhler and Paris curves are simulatively generated under multiple deformation modes and compared with data from the literature.

工程材料和结构在产品的整个生命周期中经常受到重复和循环的载荷。几十年来，预测这种载荷下的疲劳失效一直是科学界感兴趣的话题。在压裂计算建模的背景下，相场法由于其以标量损伤场的形式在连续统内对裂缝进行建模的优雅方式，近年来引起了人们的广泛关注。也有越来越多的文献提出在相场框架内对疲劳效应进行数值模拟。然而，现有的大部分工作集中在小变形范围内金属材料的弹性和弹塑性行为。聚合物的疲劳公式也很大程度上局限于Neo-Hookean模型。在目前的工作中，我们提出了一个建模框架，可以应用于应变硬化弹性体材料的疲劳裂纹扩展的数值模拟，其中聚合物链的不可扩展性被纳入使用类根材料模型。系统地进行了越来越复杂的数值研究，以举例说明该模型的显著特征。另外，模拟生成了多种变形模式下的Wöhler和Paris曲线，并与文献数据进行了对比。

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引用次数: 0

Oblique impact behavior of bio-inspired turtle shell suture interfaces 仿生龟壳缝合界面的斜冲击行为

IF 4.2 2区工程技术 Q1 MECHANICS

European Journal of Mechanics A-Solids

Pub Date : 2026-01-13 DOI: 10.1016/j.euromechsol.2026.106028

Xu Zhang , Tom Allen , Shouji Zhao , Wu Yan , Qiang Fu , Zhenqing Wang

The study investigates the dynamic response of bionic suture interfaces inspired by turtle shell under oblique impact at angles of 0°, 15°, 30°, 45°, and 60°. Four geometric configurations (triangular, trapezoidal, anti-trapezoidal, and rectangular) are examined numerically. Results demonstrate that increasing the impact angle enhances frictional energy dissipation through impactor sliding, accompanied by greater energy absorption, structural deformation, and damage area. The interdigitated suture design effectively suppresses interlaminar slippage under oblique loading. When impact occurs perpendicular to the tip angle, the structural response resembles that of a conventional flat plate under normal impact, exhibiting comparatively inferior mechanical performance. Among the tested geometries, the triangular suture interface outperforms others in impact resistance. At identical impact angles, the load-bearing capacities of anti-trapezoidal, trapezoidal, and triangular interfaces exceed that of the rectangular interfaces by 23 %–37 %, 19 %–40 %, and 81 %–89 %, respectively. Notably, the triangular suture with a tip angle of 4.6° demonstrates optimal performance. This systematic study provides valuable data on the oblique impact behavior of bioinspired suture interfaces, offering fundamental guidance for the design of advanced protective composites and bioinspired artificial armor systems.

研究了以龟壳为灵感的仿生缝合界面在0°、15°、30°、45°和60°角度的斜冲击下的动态响应。四种几何构型（三角形、梯形、反梯形和矩形）进行了数值检验。结果表明：增大冲击角能增强冲击块滑动的摩擦能耗散，同时能吸收增大，结构变形增大，损伤面积增大；指间缝线设计有效地抑制了斜载荷下的层间滑移。当冲击发生在垂直于尖端角时，结构响应与传统平板在正常冲击下的响应相似，力学性能相对较差。在测试的几何形状中，三角形缝合界面的抗冲击性优于其他几何形状。在相同的冲击角度下，反梯形界面、梯形界面和三角形界面的承载能力分别比矩形界面高出23% ~ 37%、19% ~ 40%和81% ~ 89%。值得注意的是，尖端角为4.6°的三角形缝线表现出最佳的性能。该系统研究为仿生缝合界面的斜冲击行为提供了有价值的数据，为先进防护复合材料和仿生人工装甲系统的设计提供了基础指导。

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引用次数: 0