Thin-Walled Structures最新文献_第7页

Aero-thermo-elastic behaviour of variable stiffness composite laminates and sandwich panels with temperature-dependent material properties 具有温度相关材料特性的变刚度复合材料层压板和夹芯板的气动热弹性行为

IF 6.6 1区工程技术 Q1 ENGINEERING, CIVIL

Thin-Walled Structures

Pub Date : 2026-05-01 Epub Date: 2026-02-27 DOI: 10.1016/j.tws.2026.114738

J.A. Moreira , F. Moleiro , A.L. Araújo , A. Pagani

This work is focused on the evaluation of the impact of temperature-dependent material properties on the linear aero-thermo-elastic flutter and buckling stability of variable stiffness composite laminates and sandwich panels with curvilinear fibres under supersonic airflow and thermal loads. To ensure a proper structural modelling, an assessment of Equivalent Single Layer and Layerwise models is also provided, involving the First- and Third-order Shear Deformation Theories as well as further refined theories based on high-order Lagrange

z

-expansions with thickness stretching. Numerical applications are centred on graphite-epoxy composite laminates and PVC foam core sandwich panels, with either unidirectional or curvilinear fibres, considering simply supported and clamped boundary conditions. It is concluded that temperature-dependent material properties can substantially decrease both critical buckling temperatures and flutter boundaries, depending on the fibre orientations, thermal expansion coefficients and boundary conditions. In particular, the temperature-dependency of the core material plays a major role on the aero-thermo-elastic stability of sandwich panels. Ultimately, the models accuracy assessment reveals that high-order theories are necessary to attain highly accurate flutter estimations for temperatures close to the critical buckling temperature, especially when considering curvilinear fibres and temperature-dependent material properties.

本文研究了在超音速气流和热载荷作用下，温度相关材料性能对变刚度曲线纤维复合材料层合板和夹层板的线性气动热弹性颤振和屈曲稳定性的影响。为了确保正确的结构建模，还提供了等效单层和分层模型的评估，包括一阶和三阶剪切变形理论，以及基于高阶拉格朗日z-展开的厚度拉伸的进一步改进理论。数值应用集中在石墨-环氧复合材料层压板和PVC泡沫芯夹层板上，具有单向或曲线纤维，考虑简单支撑和夹紧的边界条件。结果表明，与温度相关的材料性能可以显著降低临界屈曲温度和颤振边界，这取决于纤维取向、热膨胀系数和边界条件。特别是芯材的温度依赖性对夹芯板的气动热弹性稳定性起着重要的作用。最后，模型的精度评估表明，对于接近临界屈曲温度的温度，特别是考虑到曲线纤维和温度相关的材料特性时，需要高阶理论来获得高精度的颤振估计。

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引用次数: 0

Investigation on shear behavior of longitudinal-plate shear connector in concrete-filled steel tube 钢管混凝土纵板剪力连接件抗剪性能研究

IF 6.6 1区工程技术 Q1 ENGINEERING, CIVIL

Thin-Walled Structures

Pub Date : 2026-05-01 Epub Date: 2026-02-19 DOI: 10.1016/j.tws.2026.114672

Yaojun Zhang , Dan Gan , Jian Jiao , Zhuocheng Tang , Yifeng Liu

In concrete-filled steel tubular (CFST) structures, the natural bond strength is often insufficient to transfer forces between the steel hollow section and the infilled concrete. This study proposed a novel longitudinal-plate shear connector to enhance the interface shear resistance of CFST columns. A total of eight CFST specimens with longitudinal-plate shear connectors and a benchmark specimen were designed and subjected to push-out tests. The test variables included the number of shear connectors, shear connector details (e.g., thickness, width, the existence of openings in the shear connector, and the hole diameter of the openings), and boundary conditions of the longitudinal-plate shear connectors. The experimental results demonstrated that longitudinal-plate shear connectors increased shear capacity by up to 725 % compared to the benchmark specimen. Based on the test results, a verified finite element model was developed on the basis of the dynamic implicit solver to conduct a detailed parametric study. Finally, the failure modes of the longitudinal-plate shear connector were analyzed in detail, and corresponding formulas for predicting the shear capacity of longitudinal-plate shear connection were proposed.

在钢管混凝土（CFST）结构中，自然粘结强度往往不足以在钢空心截面和填充混凝土之间传递力。为了提高钢管混凝土柱的界面抗剪能力，提出了一种新型的纵板剪力连接件。设计了8个纵板剪力连接钢管混凝土试件和1个基准试件，并进行了推拔试验。试验变量包括剪切连接件的数量、剪切连接件的细节（如厚度、宽度、剪切连接件上是否有孔洞、孔洞的孔径）以及纵板剪切连接件的边界条件。试验结果表明，与基准试件相比，纵板剪力连接件的抗剪能力提高了725%。根据试验结果，建立了基于动态隐式求解器的验证有限元模型，进行了详细的参数化研究。最后，对纵板剪力连接件的破坏模式进行了详细分析，并提出了相应的纵板剪力连接件抗剪承载力预测公式。

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引用次数: 0

Ballistic performance and protection mechanism of PDA-CNT modified UHMWPE composite 聚丙烯腈-碳纳米管改性超高分子量聚乙烯复合材料的弹道性能及防护机理

IF 6.6 1区工程技术 Q1 ENGINEERING, CIVIL

Thin-Walled Structures

Pub Date : 2026-05-01 Epub Date: 2026-02-27 DOI: 10.1016/j.tws.2026.114737

Peng Liu , Xinyu Yao , Chaohe Ma , Hongyuan Zhou , Hong Zhang

During ballistic impact, the low surface energy of Ultra-high-molecular-weight polyethylene (UHMWPE) often results in severe interlaminar crack expansion. This study develops a polydopamine-carbon nanotube (PDA-CNT) modified UHMWPE composite. Tensile and peeling experiments show that a 0.01% concentration of CNT has the best modifying effect: the tensile modulus and strength increase by 37%, and the interlayer peeling force increase by 85%. Double Cantilever Beam (DCB) test shows that the mode Ⅰ fracture toughness increases by 117.2%, from 0.87 kJ/mm² to 1.89 kJ/mm². Ballistic experiments show a slight increase in the ballistic limit and a significant reduction in crack extension (from 67.2 mm to 47.8 mm). Finite element analysis (FEA) reveals that the modified laminate exhibits fewer failed cohesive elements and a 34.2% reduction in the delamination area. Compared to the pure target, modification dissipates the projectile’s energy through less kinetic energy but more delamination damage energy. In the secondary impact, the modification reduces the back-face deformation (BFD) from 14.5 mm to 7.8 mm, achieving a 46% reduction. Modification mitigates the superposition effect of multiple impacts on damage and the probability of subsequent projectile impacts on delaminated areas. This modification method could be applied to the protective equipment demanding repeated impact resistance.

超高分子量聚乙烯（UHMWPE）在弹道冲击过程中，由于其表面能较低，往往会导致严重的层间裂纹扩展。本研究开发了一种聚多巴胺-碳纳米管（PDA-CNT）修饰的超高分子量聚乙烯复合材料。拉伸和剥离实验表明，0.01%浓度的碳纳米管改性效果最好，拉伸模量和强度提高37%，层间剥离力提高85%。双悬臂梁（DCB）试验表明，Ⅰ模态断裂韧性提高了117.2%，从0.87 kJ/mm2提高到1.89 kJ/mm2。弹道试验表明，弹道极限略有提高，裂纹扩展明显减小（从67.2 mm减小到47.8 mm）。有限元分析表明，改进后的层合板具有更少的失效内聚单元，分层面积减少34.2%。与纯靶相比，改型通过更少的动能和更多的分层损伤能量来耗散弹丸能量。在二次冲击中，修改后的后面变形（BFD）从14.5 mm减少到7.8 mm，减少了46%。修正减轻了多重冲击对损伤的叠加效应和后续弹丸对分层区域的冲击概率。该改进方法可适用于要求耐反复冲击的防护装备。

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引用次数: 0

Local plastic deformation prediction of spherical and cylindrical pressure hulls subject to underwater shock loading 水下冲击载荷作用下球形和圆柱形耐压壳体的局部塑性变形预测

IF 6.6 1区工程技术 Q1 ENGINEERING, CIVIL

Thin-Walled Structures

Pub Date : 2026-05-01 Epub Date: 2026-02-14 DOI: 10.1016/j.tws.2026.114674

Fu-Jin Yang , Zhao-Li Tian , Jun Guo , Fei Zhao

Pressure hulls of underwater vehicles, typically configured as spherical or cylindrical structures, are vulnerable to localized damage when subjected to shock loads from underwater explosions. This study establishes theoretical models for deformation patterns and deformation center deflection of such hulls under underwater shock by integrating fluid–structure interaction theory, localized deformation mechanics, and structural dynamics. Systematic investigations are conducted to evaluate the influence of hull thickness

h

, diameter

D

, length

L

, shock factor

I

, and hydrostatic pressure

p_{\infty}

. The deformation center deflection

w_{0}

is found to scale as

w_{0} \propto h^{- 2}

with thickness,

w_{0} \propto \sqrt{D}

with diameter,

w_{0} \propto L^{- 0.5}

with length,

w_{0} / D \propto I^{2}

with shock factor, and

w_{0} / D \propto p_{\infty}

with hydrostatic pressure. Results show that spherical hulls of equal diameter exhibit superior shock resistance, and hull thickness plays a particularly significant role in mitigating shock effects. The proposed deformation patterns and deflection metrics provide a practical basis for evaluating shock resistance and assessing pressure-bearing capacity and implosion risks in damaged underwater hulls.

水下航行器的耐压壳通常为球形或圆柱形结构，在受到水下爆炸的冲击载荷时容易受到局部损伤。本研究结合流固耦合理论、局部变形力学和结构动力学，建立了水下冲击下该类船体变形模式和变形中心挠度的理论模型。对船体厚度h、直径D、长度L、冲击系数I和静水压力p∞的影响进行了系统的研究。变形中心挠度w0按厚度w0∝h−2，直径w0∝D，长度w0∝L−0.5，冲击因子w0/D∝I2，静水压力w0/D∝p∞。结果表明，等直径的球形船体具有较好的抗冲击性能，其中船体厚度对减轻冲击效果的作用尤为显著。提出的变形模式和挠度指标为评估受损水下船体的抗冲击能力、承压能力和内爆风险提供了实用依据。

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引用次数: 0

Rigidity paradox of kirigami arches 基里美拱的刚性悖论

IF 6.6 1区工程技术 Q1 ENGINEERING, CIVIL

Thin-Walled Structures

Pub Date : 2026-05-01 Epub Date: 2026-02-17 DOI: 10.1016/j.tws.2026.114691

Eszter Fehér

The geometry of bending-active kirigami arches, decorated by cuts and holes, is strongly influenced by the location and geometry of the perforations. This study demonstrates that, in some instances, the geometric strengthening induced by additional cuts can outweigh the weakening effect of material removal, leading to a counterintuitive increase in structural rigidity under a given concentrated load. We present multiple parametric cut patterns to show that rigidity can be increased both under symmetric and asymmetric loads. While the preferred cut location is often near the point of action of the load, asymmetric loading can shift this optimum elsewhere. Moreover, the distance between the supports also plays a crucial role, namely, the rigidity gain vanishes when the supports are too far apart. We found that the rigidity can be increased for both non-perforated and perforated sheets, and there is a non-monotonic relationship between the global porosity and the rigidity of the structure. Numerical predictions are validated against experimental measurements.

由切口和孔洞装饰的弯曲主动基里伽米拱门的几何形状受到孔洞的位置和几何形状的强烈影响。该研究表明，在某些情况下，额外切割引起的几何强化可能超过材料去除的弱化效应，导致在给定集中载荷下结构刚度的反直觉增加。我们提出了多个参数切割模式，以表明在对称和非对称载荷下刚度都可以增加。虽然首选切割位置通常在载荷作用点附近，但不对称载荷可以将此最佳位置转移到其他地方。此外，支座之间的距离也起着至关重要的作用，即当支座间距过大时，刚度增益消失。我们发现，无论是无孔板还是有孔板，结构刚度都可以增加，并且整体孔隙率与结构刚度之间存在非单调关系。数值预测与实验测量结果相对照。

引用次数: 0

Tensile behavior of corroded high-strength steel components after fire under air and foam cooling 腐蚀高强钢构件火灾后空气和泡沫冷却下的拉伸性能

IF 6.6 1区工程技术 Q1 ENGINEERING, CIVIL

Thin-Walled Structures

Pub Date : 2026-05-01 Epub Date: 2026-02-12 DOI: 10.1016/j.tws.2026.114670

Chunlei Xu , Wenyu Cai , Guo-Qiang Li

In engineering practice, many steel structures in service are inevitably corroded, making them more susceptible to severe damage after exposure to fire. Therefore, assessing the post-fire tensile properties of corroded structural steel is crucial. This study conducted tensile tests on Q690 high-strength structural steel components, subjected to varying levels of corrosion, heating temperatures, and cooling methods (air cooling and foam fire extinguishing agent cooling), to examine their stress-strain behavior, reduction coefficient of mechanical properties, failure modes, and surface strain fields under these combined factors. A predictive model incorporating the combined effects of corrosion, exposure temperature, and cooling method was developed to describe the post-fire mechanical properties of the corroded Q690 steel. In addition, a 3D scanner was used to analyze the damaged surface morphology of the tensile components. The obtained corrosion morphology was then imported into the finite element model for numerical analysis using three-dimensional reverse reconstruction technology. According to this study, below 500 °C, corrosion was the main factor influencing the strength. Above 500 °C, temperature became the dominant factor, with strength decreasing rapidly as temperature increased. When the exposure temperature exceeded 700 °C, the influence of cooling methods on the mechanical properties of steel became pronounced. High temperatures also caused the corrosion-induced pits to expand. The damage depth generally followed a normal distribution, and as the pit depth increased, stress triaxiality increased while fracture equivalent plastic strain decreased.

在工程实践中，许多使用中的钢结构不可避免地会发生腐蚀，这使得钢结构在火灾后更容易受到严重的破坏。因此，评估腐蚀结构钢的火灾后拉伸性能至关重要。本研究对Q690高强度结构钢构件进行了不同程度的腐蚀、加热温度和冷却方式（空气冷却和泡沫灭火剂冷却）下的拉伸试验，考察了这些综合因素下的应力-应变行为、力学性能折减系数、失效模式和表面应变场。建立了一个综合腐蚀、暴露温度和冷却方法影响的预测模型来描述腐蚀后Q690钢的火灾力学性能。此外，利用三维扫描仪对拉伸构件的损伤表面形貌进行了分析。将得到的腐蚀形态导入有限元模型，采用三维逆向重构技术进行数值分析。根据本研究，在500℃以下，腐蚀是影响强度的主要因素。在500℃以上，温度成为主导因素，随着温度的升高，强度迅速下降。当暴露温度超过700℃时，冷却方式对钢力学性能的影响明显。高温还会导致腐蚀引起的凹坑扩大。损伤深度大体上服从正态分布，随着坑深的增加，应力三轴性增大，断裂等效塑性应变减小。

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引用次数: 0

Magnetoelastic free vibration of a microplate on an elastic foundation 弹性基础上微板的磁弹性自由振动

IF 6.6 1区工程技术 Q1 ENGINEERING, CIVIL

Thin-Walled Structures

Pub Date : 2026-05-01 Epub Date: 2026-02-12 DOI: 10.1016/j.tws.2026.114652

Xin Li , Mengxue Xie , Jianbo Feng , Yuda Hu

While previous studies on magnetoelastic plates have provided foundational insights, the combined roles of magnetic saturation and a two-parameter elastic foundation within a consistent size-dependent framework remain less explored, limiting the prediction accuracy for nonlinear stiffness characteristics. This study investigates the magnetoelastic coupled nonlinear vibration of a four-edge simply supported ferromagnetic microplate resting on an elastic foundation under a transverse magnetic field. A magnetization force model is developed by incorporating the nonlinear magnetization behavior and magnetic saturation effects of the ferromagnetic material. Based on the modified strain gradient theory (MGST) and Kirchhoff plate theory, with due consideration of geometric nonlinearity, the kinetic and strain energies of the microplate accounting for size effects are formulated. The additional deformation energy induced by the Winkler–Pasternak elastic foundation is also derived. The nonlinear magneto-elastic coupling vibration equations are established via Hamilton’s variational principle. Using the Galerkin method combined with the method of multiple scales, the second-order analytical expressions for the nonlinear natural frequencies of the coupled system are obtained. Numerical case studies are conducted to examine the variations of microplate deflection and natural frequency under the combined effects of the magnetic field and elastic foundation. The results indicate that the deflection increases with magnetic field intensity but decreases with foundation stiffness parameters. More importantly, the coupled effects of the microplate, magnetic field, and elastic foundation lead to distinct softening-hardening spring transitions, a complex nonlinear behavior originating from the interplay between magnetic saturation and the Pasternak foundation's shear layer.

虽然以前对磁弹性板的研究已经提供了基本的见解，但在一致的尺寸依赖框架内，磁饱和和双参数弹性基础的综合作用仍然很少被探索，这限制了非线性刚度特性的预测精度。研究了弹性基础上四边简支铁磁微板在横向磁场作用下的磁弹性耦合非线性振动。结合铁磁材料的非线性磁化行为和磁饱和效应，建立了磁化力模型。基于修正应变梯度理论（MGST）和Kirchhoff板理论，在考虑几何非线性的基础上，导出了考虑尺寸效应的微孔板的动力学能和应变能。推导了温克勒-帕斯捷尔纳克弹性地基引起的附加变形能。利用Hamilton变分原理建立了非线性磁弹性耦合振动方程。利用伽辽金法结合多尺度法，得到了耦合系统非线性固有频率的二阶解析表达式。通过数值算例研究了磁场和弹性地基共同作用下微板挠度和固有频率的变化规律。结果表明，挠度随磁场强度的增大而增大，随地基刚度参数的增大而减小。更重要的是，微孔板、磁场和弹性地基的耦合作用导致了明显的软化-硬化弹簧转变，这是一种复杂的非线性行为，源于磁饱和与帕斯捷尔纳克地基剪切层的相互作用。

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引用次数: 0

Investigation on entrance and exit delamination damage in drilling CF/PEEK via experimental and machine learning approaches 基于实验和机器学习方法的CF/PEEK钻井进出口分层损伤研究

IF 6.6 1区工程技术 Q1 ENGINEERING, CIVIL

Thin-Walled Structures

Pub Date : 2026-05-01 Epub Date: 2026-02-12 DOI: 10.1016/j.tws.2026.114663

Zhijian Meng , Shunuan Liu , Yuchen Cai , Qi Yang , Bin Luo , Kaifu Zhang

As a thermoplastic composite with superior sustainability and mechanical performance, carbon fiber reinforced polyetheretherketone (CF/PEEK) has become the preferred material for fabricating prototype components in next-generation aircraft applications. However, drilling-induced delamination damage is prone to occur due to the material’s anisotropy and lamination characteristics, severely compromising the service reliability of CF/PEEK components. This study focuses on the entrance and exit delamination damage in drilling CF/PEEK. Specifically, drilling experiments under various parameters are conducted to examine the distribution characteristics and formation mechanisms of delamination. Subsequently, considering thrust force, torque, and drilling temperature, a small-sample sensitivity analysis framework based on a hyperparameter-optimized support vector regression (SVR) model and the Sobol method is developed to identify sensitivity factors influencing delamination. The results indicate that delamination primarily occurs within the fiber cutting angle range of 90°-180°, where fiber bending fractures lead to an increase in subsurface damage. The hole entrance primarily exhibits mode Ⅲ delamination caused by intralaminar tearing, whereas the hole exit primarily exhibits mode III delamination, accompanied by mode I delamination due to interlaminar debonding. Furthermore, torque is identified as the most sensitive factor influencing both entrance and exit delamination. Compared to entrance delamination, the exit delamination is more susceptible to interactions among multiple factors.

作为一种具有优异可持续性和机械性能的热塑性复合材料，碳纤维增强聚醚醚酮（CF/PEEK）已成为制造下一代飞机原型部件的首选材料。然而，由于材料的各向异性和层压特性，容易发生钻井引起的脱层损伤，严重影响CF/PEEK组件的使用可靠性。本文主要研究了CF/PEEK钻井的进出口分层损伤。具体而言，通过不同参数下的钻孔实验，研究脱层的分布特征和形成机制。随后，考虑推力、扭矩和钻井温度，建立了基于超参数优化支持向量回归（SVR）模型和Sobol方法的小样本灵敏度分析框架，识别影响分层的敏感性因素。结果表明：在纤维切割角度为90°~ 180°范围内，分层主要发生，纤维弯曲断裂导致亚表面损伤增加；孔口主要表现为层间撕裂引起的Ⅲ型分层，孔口主要表现为III型分层，同时伴有层间脱粘引起的I型分层。此外，扭矩是影响入口和出口分层的最敏感因素。与入口分层相比，出口分层更容易受到多种因素相互作用的影响。

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引用次数: 0

Experimental and numerical analysis on progressive failure of hat-stiffened composite panels under four-point bending: effect of skin stiffness variation 帽加筋复合材料板四点弯曲渐进式破坏试验与数值分析：蒙皮刚度变化的影响

IF 6.6 1区工程技术 Q1 ENGINEERING, CIVIL

Thin-Walled Structures

Pub Date : 2026-05-01 Epub Date: 2026-02-12 DOI: 10.1016/j.tws.2026.114665

Tianyu Wu , Jiafan Feng , Bojian Li , Bowen Gong , Yuzhong Ge , Wenting Ouyang , Huan Wang , Han Wang , Hua-Xin Peng

Hat-stiffened composite panels are critical structural components of aircraft fuselages, resisting significant bending loads under service conditions. Increasing skin stiffness is considered an approach to enhance their bending performance. In this study, specimens with three skin configurations were used, namely SP-12 (12-ply skin), SP-16 (16-ply skin), and SP-26 (26-ply skin). The effect of varying skin stiffness on four-point bending process was investigated through experiment and progressive damage simulation. It was observed that SP-12 exhibited brittle failure characterized by a single load drop, while SP-16 and SP-26 exhibited progressive failure characterized by multiple load drops. Higher skin stiffness significantly enhanced both initial damage load and final debonding failure load, while reducing the bending deformation. This was because increasing skin stiffness required higher load to drive bending deformation, while the interface strength was not enhanced. Varying skin stiffness altered the shear stress distribution, leading to additional debonding and changes in fracture mode at stringer-filler co-curing interface in SP-16 and SP-26. Delamination also occurred at stringer corners in these specimens affected by higher damage load. This also caused severe intralayer damage and cracks under higher load-bearing capability induced by skin stiffness increasing. Based on the above observations, this study provides insights into improving the bending performance of hat-stiffened composite panels.

帽加筋复合材料板是飞机机身的关键结构部件，在使用条件下可承受巨大的弯曲载荷。增加蒙皮刚度被认为是提高其弯曲性能的一种方法。本研究使用了三种皮肤形态的标本，分别是SP-12（12层）、SP-16（16层）和SP-26（26层）。通过实验和渐进损伤模拟研究了不同蒙皮刚度对四点弯曲过程的影响。SP-12表现为单次载荷下降的脆性破坏，而SP-16和SP-26表现为多次载荷下降的渐进式破坏。较高的蒙皮刚度显著提高了初始损伤载荷和最终脱粘破坏载荷，同时降低了弯曲变形。这是因为增加蒙皮刚度需要更高的载荷来驱动弯曲变形，而界面强度没有提高。表面刚度的变化改变了SP-16和SP-26的剪切应力分布，导致了筋填料共固化界面的额外剥离和断裂模式的变化。在受较高损伤载荷影响的试件中，弦角处也出现分层现象。这也造成了严重的层内损伤和裂缝在较高的承载能力下引起的皮肤刚度增加。基于上述观察结果，本研究为提高帽加筋复合材料板的弯曲性能提供了见解。

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引用次数: 0

Designing lightweight nanolattices: multiscale optimization of geometry and size effects 设计轻量化纳米晶格：几何和尺寸效应的多尺度优化

IF 6.6 1区工程技术 Q1 ENGINEERING, CIVIL

Thin-Walled Structures

Pub Date : 2026-05-01 Epub Date: 2026-02-21 DOI: 10.1016/j.tws.2026.114704

Hyoui Yoon , Hyobi Lee , Sangryun Lee

Lattice–truss structures have emerged as lightweight architected materials capable of achieving exceptional stiffness-to-weight ratios through geometry-driven design. Nanolattice architectures—composed of periodic networks of nanoscale beams—offer an opportunity to realize lightweight yet mechanically robust materials, whose properties can surpass those of bulk alternatives. However, the mechanical behavior of nanolattices remains difficult to predict accurately, as intrinsic size effects due to surface stresses can substantially alter nanolattice properties. Although multiscale approaches coupling atomistic simulations with continuum models have been employed, the individual contributions of surface-induced stresses and geometric design to nanolattice stiffness have not been clearly distinguished. To address this issue, this study introduces a unified multiscale framework that explicitly separates and quantifies surface-stress effects and beam geometry effects in nanolattice structures. By coupling molecular statics (MS) simulations with finite element analysis (FEA), the mechanical behaviors of body-centered (BC) and octet-truss (OT) lattices are evaluated under controlled beam geometries and lattice size variations. The results demonstrate that the optimal geometries identified at the continuum scale remain valid at the nanoscale when surface effects are incorporated. Surface-stress-corrected MS results exhibit strong agreement with FEA predictions, confirming that geometry-driven stress redistribution, rather than intrinsic surface tension, governs the effective stiffness response. Both BC and OT lattices exhibit a size-dependent stiffening trend, originating from the increase in the axial stiffness of individual nanobeams as their diameter decreases. These findings elucidate how geometry, scale, and surface energy collectively govern mechanical stiffness in nanolattices, providing fundamental design guidelines for lightweight and high-stiffness nanoscale architectures.

格架结构已经成为一种轻质建筑材料，能够通过几何驱动设计实现特殊的刚度-重量比。纳米晶格结构——由纳米级光束的周期性网络组成——提供了一个实现轻量化但机械坚固的材料的机会，其性能可以超过那些块状替代品。然而，纳米晶格的力学行为仍然难以准确预测，因为表面应力引起的固有尺寸效应可以大大改变纳米晶格的性质。虽然已经采用了多尺度方法将原子模拟与连续介质模型相结合，但表面诱导应力和几何设计对纳米晶格刚度的单独贡献尚未得到明确区分。为了解决这个问题，本研究引入了一个统一的多尺度框架，明确地分离和量化纳米晶格结构中的表面应力效应和梁几何效应。通过分子静力学（MS）模拟与有限元分析（FEA）相结合的方法，研究了受控梁几何形状和晶格尺寸变化下体心（BC）和八元桁架（OT）晶格的力学行为。结果表明，当考虑表面效应时，在连续尺度上确定的最佳几何形状在纳米尺度上仍然有效。表面应力校正的质谱结果与有限元预测结果非常吻合，证实了几何驱动的应力重分布，而不是固有的表面张力，决定了有效的刚度响应。BC和OT晶格都表现出与尺寸相关的硬化趋势，这源于单个纳米梁的轴向刚度随着其直径的减小而增加。这些发现阐明了几何、尺度和表面能如何共同控制纳米晶格的机械刚度，为轻量化和高刚度纳米尺度结构提供了基本的设计指导。

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引用次数: 0