Composite Structures最新文献_第8页

Nozzle size-encoded direct 4D printing with enhanced interfacial strength 喷嘴尺寸编码直接4D打印，增强界面强度

IF 7.1 2区材料科学 Q1 MATERIALS SCIENCE, COMPOSITES

Composite Structures

Pub Date : 2025-12-26 DOI: 10.1016/j.compstruct.2025.119997

Fangfang Wang , Yao Wang , Jiaxin Li , Xiaoshan Cao , Chao Yuan

Fused deposition modeling (FDM) 3D printing naturally allows for shape memory programming of extruded thermoplastic polymers during the extrusion/solidification process, which has an inherent compatibility with direct 4D printing. However, the current FDM-based 4D printing methods with non-ideal processing conditions or reduced miscibility of heterogeneous materials increase the microscopic defects that deteriorate the interfacial strength. Herein, we propose a nozzle-size-encoded direct 4D printing approach that achieves tailorable shapeshifting and enhanced interfacial strength. A linear correlation between the heat-induced shrinkage strain of printed filaments and the normalized outlet diameter of the print nozzle is mathematically derived, and validated through experiments. Based on this mechanism, we design laminated structures that serve as basic units to construct self-deployable lattice networks exhibiting bidirectional shrinkage, zero Poisson’s ratio, or unidirectional elongation. Moreover, by virtue of the good chain miscibility of a single type of thermoplastic polymer, the dual-nozzle-size-printed polylactic acid (PLA) specimen shows higher interfacial strength than the conventional PLA-thermoplastic urethane (TPU) bilayer design. Overall, the proposed method provides a simple yet high-quality route for creating complex structures via stimuli-responsive shapeshifting, paving the way for potential applications in smart metamaterials and deployable structures.

熔融沉积建模（FDM） 3D打印自然允许在挤出/凝固过程中对挤出的热塑性聚合物进行形状记忆编程，这与直接4D打印具有固有的兼容性。然而，目前基于fdm的4D打印方法，由于加工条件不理想或非均质材料的混相性降低，增加了微观缺陷，降低了界面强度。在此，我们提出了一种喷嘴尺寸编码的直接4D打印方法，可实现可定制的变形和增强的界面强度。从数学上推导了打印细丝的热收缩应变与打印喷嘴归一化出口直径之间的线性关系，并通过实验进行了验证。基于这种机制，我们设计了层压结构，作为基本单元来构建具有双向收缩、零泊松比或单向伸长的自展开晶格网络。此外，由于单一类型的热塑性聚合物具有良好的链混相性，双喷嘴尺寸印刷的聚乳酸（PLA）样品比传统的PLA-热塑性聚氨酯（TPU）双层设计具有更高的界面强度。总的来说，所提出的方法为通过刺激响应变形创建复杂结构提供了一种简单而高质量的途径，为智能超材料和可展开结构的潜在应用铺平了道路。

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引用次数: 0

Application of machine learning algorithms in predicting ultimate load of EBROG FRP-to-concrete joints in single-lap shear tests 机器学习算法在预测EBROG frp -混凝土节点单搭剪极限荷载中的应用

IF 7.1 2区材料科学 Q1 MATERIALS SCIENCE, COMPOSITES

Composite Structures

Pub Date : 2025-12-25 DOI: 10.1016/j.compstruct.2025.120005

Shokouh Zolfaghari, Shakiba Zolfaghari, Davood Mostofinejad

It is well established that the externally-bonded reinforcement on grooves (EBROG) technique outperforms the traditional externally-bonded reinforcement (EBR) method in strengthening concrete elements with fiber-reinforced polymer (FRP) sheets primarily by delaying or preventing debonding, which allows for more effective stress transfer and results in higher load capacity and improved ductility. Due to the presence of the grooves, the bonding mechanism of FRP sheets to concrete using the EBROG technique is more complex than that of the EBR method, and understanding the influence of various groove-related parameters remains a challenge. This study explores how variations in groove geometry (width, depth, and spacing), concrete compressive strength, and FRP sheet properties affect the ultimate load of the FRP sheet-to-concrete bond with the groove classes of b_g × h_g@s (groove width × depth @ spacing). To better understand the contribution of each factor, the extreme gradient boosting (XGBoost) model was employed as a supportive analytical tool, yielding a strong predictive performance with an R² of 0.9041. The results indicated that for concrete compressive strengths in the range of 25–45 MPa, the 5 × 10@15 mm groove class was identified as the optimal and practically applicable configuration. This groove geometry resulted in ultimate bond loads of 12.42, 13.16, and 13.49 kN for concrete compressive strengths of 25, 35, and 45 MPa, respectively. However, at a concrete compressive strength of 55 MPa, the highest ultimate load of 10.97 kN was achieved with the 10 × 10@45 mm groove class. According to the Gain feature importance analysis, the width and fiber stiffness in the FRP sheet were the most influential parameters in predicting the ultimate bond load, while groove width and concrete compressive strength had the least impact.

众所周知，沟槽外粘接加固（EBROG）技术优于传统的外粘接加固（EBR）方法，主要通过延迟或防止纤维增强聚合物（FRP）板的剥离来增强混凝土元件，从而允许更有效的应力传递，从而提高承载能力和延性。由于沟槽的存在，使用EBROG技术研究FRP片材与混凝土的粘合机制比使用EBR方法更为复杂，并且了解各种沟槽相关参数的影响仍然是一个挑战。本研究探讨了沟槽几何形状（宽度、深度和间距）、混凝土抗压强度和FRP片材性能的变化如何影响FRP片材与bg × hg@s（沟槽宽度×深度@间距）的沟槽等级对混凝土粘结的最终载荷。为了更好地了解每个因素的贡献，我们采用极端梯度提升（XGBoost）模型作为辅助分析工具，得到了较强的预测性能，R2为0.9041。结果表明，在混凝土抗压强度为25 ~ 45 MPa范围内，5 × 10@15 mm槽级是最优且实际适用的配置；当混凝土抗压强度分别为25、35和45 MPa时，这种沟槽几何结构的极限粘结载荷分别为12.42、13.16和13.49 kN。而在混凝土抗压强度为55 MPa时，10 × 10@45 mm槽级最高极限荷载为10.97 kN。根据增益特征重要性分析，FRP片材的宽度和纤维刚度是预测极限粘结荷载的最大影响参数，而槽宽和混凝土抗压强度的影响最小。

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引用次数: 0

Modeling and evaluation for nonlinear vibration, nonlinear bending and thermal postbuckling of multi-auxetic sandwich beams with porosity-dependent GPL-reinforced metal core 含孔隙度相关gpl增强金属芯的多氧夹层梁非线性振动、非线性弯曲和热后屈曲的建模与评价

IF 7.1 2区材料科学 Q1 MATERIALS SCIENCE, COMPOSITES

Composite Structures

Pub Date : 2025-12-25 DOI: 10.1016/j.compstruct.2025.120007

Hui-Shen Shen, Zhouyu Zheng, Xiuhua Chen

Graphene platelet (GPL)-reinforced metal foams with negative Poisson’s ratio (NPR) have emerged as a novel advanced engineering materials. In this study, we design a new multi-auxetic sandwich beam, where the core layer consists of GPL-reinforced (GPLR) porous metal foam, and the facesheets are composite laminates, both exhibiting NPR properties. We investigate small and large amplitude vibrations, nonlinear bending, as well as thermal buckling and postbuckling of multi-auxetic sandwich beams with GPLR porous cores and NPR laminated facesheets supported by elastic foundations. The thermo-mechanical properties of laminated facesheets are temperature-dependent, while the material properties of GPLR metal foam core are porosity-dependent and temperature-dependent. Within the framework of Reddy-Levinson shear deformation beam theory, the governing equations of motion are established for an auxetic sandwich beam where both the core and facesheets exhibit NPR characteristics. The modeling process incorporates the von Kármán nonlinear strain–displacement relationships, the beam-foundation interaction and the thermal effects. A two-step perturbation approach is employed for solving perturbation equations step by step, yielding asymptotic analytical solutions for geometric nonlinear problems of the multi-auxetic sandwich beam. Numerical investigations intended to supply information on the influence played by a number of parameters are performed. A performance evaluation is conducted by comparing numerical results between auxetic and non-auxetic sandwich beams.

负泊松比（NPR）石墨烯血小板（GPL）增强金属泡沫是一种新型的先进工程材料。在这项研究中，我们设计了一种新的多auxetic夹层梁，其中核心层由gpl增强（GPLR）多孔金属泡沫组成，而面板是复合层压板，两者都具有NPR特性。我们研究了弹性基础支撑下具有GPLR多孔芯和NPR层压面板的多氧夹层梁的小振幅和大振幅振动、非线性弯曲以及热屈曲和后屈曲。层合板的热机械性能与温度有关，而GPLR金属泡沫芯的材料性能与孔隙率和温度有关。在Reddy-Levinson剪切变形梁理论的框架下，建立了芯板和面板均具有NPR特性的剪切夹层梁的运动控制方程。建模过程中考虑了von Kármán非线性应变-位移关系、梁-基础相互作用和热效应。采用两步摄动法逐级求解摄动方程，得到了多辅助夹层梁几何非线性问题的渐近解析解。进行了数值研究，旨在提供有关若干参数所起影响的信息。通过数值计算结果的对比，对减震夹层梁与非减震夹层梁的性能进行了评价。

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引用次数: 0

Non-Linear thermal instability behavior of moderately thick variable stiffness laminated composite cylindrical shell panels 中厚变刚度层合复合材料圆柱壳板的非线性热失稳行为

IF 7.1 2区材料科学 Q1 MATERIALS SCIENCE, COMPOSITES

Composite Structures

Pub Date : 2025-12-25 DOI: 10.1016/j.compstruct.2025.120010

Satyajeet Dash , Sumeet Chakraborty , Tanish Dey

This study proposes a semi-analytical framework to investigate the post-buckling behavior of variable stiffness laminated composite (VSLC) shallow cylindrical shell panels subjected to thermal environments. Incorporating first-order shear deformation theory (FSDT), the model accurately predicts the response of moderately thick VSLC panels. The in-plane stress distribution, inherently non-uniform due to varying fiber paths, is determined via membrane strain energy minimization. The displacement functions are generated using the Gram-Schmidt orthogonalization process. Substituting the orthogonal displacement functions into the energy equation and minimizing it yields the governing equations, which are further reduced to a system of non-linear algebraic equations. The non-linear equilibrium paths are efficiently traced utilizing the Crisfield arc-length approach. Numerical results demonstrate that variations in fiber angles and panel curvature significantly influence post-buckling responses. Optimal fiber orientations, panel geometries, and boundary conditions play pivotal roles in enhancing post-buckling strength, with both symmetric and unsymmetric laminates showing distinct advantages depending on support conditions. These findings offer practical guidelines for the design of thermally resilient composite structures, particularly in aerospace applications and other high-performance systems demanding robust stability under thermal loads.

本研究提出了一个半解析框架来研究变刚度层合复合材料（VSLC）浅圆柱壳板在热环境下的后屈曲行为。该模型结合一阶剪切变形理论（FSDT），能较准确地预测中厚VSLC板的响应。平面内应力分布，固有的不均匀，由于不同的纤维路径，是确定通过膜应变能最小化。利用Gram-Schmidt正交过程生成位移函数。将正交位移函数代入能量方程并将其最小化，得到控制方程，并进一步简化为非线性代数方程组。利用Crisfield弧长方法有效地跟踪非线性平衡路径。数值结果表明，纤维角度和板曲率的变化对屈曲后响应有显著影响。最佳的纤维取向、板的几何形状和边界条件在提高屈曲后强度方面起着关键作用，对称和非对称层压板在不同的支撑条件下都表现出明显的优势。这些发现为热弹性复合材料结构的设计提供了实用指南，特别是在航空航天应用和其他高性能系统中，需要在热负荷下具有强大的稳定性。

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引用次数: 0

Ultra-lightweight and flexible CFRP honeycomb and bending behaviors of CFRP honeycomb-core sandwich panels 超轻柔性CFRP蜂窝及CFRP蜂窝芯夹芯板的弯曲性能

IF 7.1 2区材料科学 Q1 MATERIALS SCIENCE, COMPOSITES

Composite Structures

Pub Date : 2025-12-24 DOI: 10.1016/j.compstruct.2025.120000

Xie Chen , Jianqin Wu , Hao Feng , Hualin Fan

To address the issues of weak interface delamination of pure carbon fiber reinforced plastic (CFRP) honeycomb cores and low mechanical performance and weight efficiency of pure foam cores, and to meet the concurrent requirements of structural lightweighting and high strength. This study proposes a new strategy for the composite core layer based on the “flexible honeycomb” design concept. This study innovatively combines foam with flexible CFRP honeycomb. By comparing the performance of pure foam core, pure flexible honeycomb core, and their composite core layer, the research found that the flexible honeycomb-foam composite core layer triggered a unique synergistic failure mechanism – the progressive buckling of the flexible honeycomb walls coupled with the constrained crushing of the foam, thereby fundamentally overcoming the interface delamination defect of pure flexible honeycomb and simultaneously significantly enhancing the shear strength and energy absorption efficiency of the pure foam core. The out-of-plane compressive properties of three types of flexible honeycomb cores and the bending responses of corresponding sandwich panels were studied. The results show that the flexural index of the CFRP honeycomb sandwich structure filled with polyurethane foam (SHF) is at least 60% higher than that of the foam core sandwich structure (SF).

解决纯碳纤维增强塑料（CFRP）蜂窝芯的界面弱分层和纯泡沫芯的力学性能和重量效率低的问题，满足结构轻量化和高强度并存的要求。本研究提出了一种基于“柔性蜂窝”设计理念的复合材料核心层新策略。本研究创新性地将泡沫与柔性CFRP蜂窝相结合。通过对比纯泡沫芯、纯柔性蜂窝芯及其复合芯层的性能，研究发现，柔性蜂窝-泡沫复合芯层触发了一种独特的协同破坏机制——柔性蜂窝壁的逐步屈曲与泡沫的约束破碎耦合；从而从根本上克服了纯柔性蜂窝的界面分层缺陷，同时显著提高了纯泡沫芯的抗剪强度和吸能效率。研究了三种柔性蜂窝芯的面外压缩性能及相应夹层板的弯曲响应。结果表明：聚氨酯泡沫填充CFRP蜂窝夹层结构（SHF）的抗弯指数比泡沫芯夹层结构（SF）的抗弯指数至少高60%；

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引用次数: 0

Anisotropy-compensated wavefield imaging: precise delamination mapping in composites via wavenumber-angle-depth analysis 各向异性补偿波场成像：通过波数-角度-深度分析在复合材料中精确分层映射

IF 7.1 2区材料科学 Q1 MATERIALS SCIENCE, COMPOSITES

Composite Structures

Pub Date : 2025-12-23 DOI: 10.1016/j.compstruct.2025.120002

Zhangchi Gao , Kan Feng , Hu Sun , Xinlin Qing

The anisotropy of composites significantly influences guided wave propagation, posing substantial challenges for ultrasonic guided-wave-based nondestructive testing. Using delamination in composite laminates as a case study, this paper first investigates the anisotropic characteristics of wavenumber during guided wave propagation and analyzes its impact on damage identification. To address this, an anisotropy-compensated damage imaging method is proposed. Finite element simulations combined with semi-analytical finite element (SAFE) analysis of wavenumber dispersion curves elucidated the unique mechanisms of wavenumber anisotropy. These simulations revealed that energy focusing along the composite’s fiber direction obscures damage information, adversely affecting guided wavefield identification. Experimentally, guided wavefields were excited using piezoelectric (PZT) transducers installed on damaged composite plates, and the out-of-plane displacement responses were recorded via a scanning laser Doppler vibrometer (SLDV). Finally, a novel wavefield imaging algorithm based on the wavenumber-angle-effective thickness relationship is introduced. This algorithm incorporates the angular parameter to comprehensively account for anisotropic effects. Validation through both simulation models and experiments demonstrated that the proposed algorithm accurately identifies the location, shape, and depth of delamination, exhibiting excellent damage identification performance.

复合材料的各向异性极大地影响了导波的传播，给基于超声导波的无损检测带来了巨大的挑战。以复合材料层合板的分层为例，研究了导波传播过程中波数的各向异性特征，并分析了其对损伤识别的影响。为了解决这一问题，提出了一种各向异性补偿损伤成像方法。有限元模拟与波数色散曲线的半解析有限元（SAFE）分析相结合，阐明了波数各向异性的独特机理。这些模拟表明，沿着复合材料纤维方向聚焦的能量模糊了损伤信息，不利地影响了导波场识别。实验中，利用安装在损伤复合材料板上的压电（PZT）换能器激发导波场，并通过扫描激光多普勒振动仪（SLDV）记录了导波场的面外位移响应。最后，提出了一种基于波数-角-有效厚度关系的波场成像算法。该算法引入了角度参数，综合考虑了各向异性效应。仿真模型和实验验证表明，该算法能够准确识别分层的位置、形状和深度，具有良好的损伤识别性能。

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引用次数: 0

MXene-SnO2 modified carbon felt electrode for enhanced performance in vanadium redox flow batteries MXene-SnO2改性碳毡电极在钒氧化还原液流电池中的应用

IF 7.1 2区材料科学 Q1 MATERIALS SCIENCE, COMPOSITES

Composite Structures

Pub Date : 2025-12-23 DOI: 10.1016/j.compstruct.2025.120001

Gurpreet Singh , Amanpreet Kaur , Jun Woo Lim

Metal oxide catalysts offer low cost, strong activity, and structural diversity, but their use in vanadium redox systems is limited by poor conductivity and small surface area. This study developed a MXene-SnO₂ composite electrode using a hydrothermal technique, followed by thermal annealing, and investigated its electrocatalytic activity in vanadium redox flow battery systems. MXene, a two-dimensional transition metal carbide, was chosen as a conductive support because of its high electrical conductivity, hydrophilicity, and abundance of surface functional groups. These properties enhance rapid electron transport and provide an accessible surface for vanadium ion interactions. SnO₂ nanoparticles, known for catalytic activity and wettability, were uniformly spread over the MXene surface, contributing to better redox and charge transfer processes. The composite demonstrated enhanced electrocatalytic activity for both VO²⁺/VO₂⁺ and V²⁺/V³⁺ couples compared with individual components. The synergistic action of MXene and SnO₂ enhances ion diffusion, electron transport, and interfacial charge transfer. Cell tests confirmed higher electrolyte performance and reduced polarization. At a current density of 100 mA/cm², the energy efficiency reached 85 %, a 5 % increase from the bare electrode. These findings suggest that mixing MXene and metal oxides is an excellent technique for creating high-performance electrocatalysts for vanadium redox flow batteries.

金属氧化物催化剂成本低，活性强，结构多样，但其在钒氧化还原体系中的应用受到导电性差和表面积小的限制。本研究采用水热法制备了MXene-SnO2复合电极，并对其在钒氧化还原液流电池中的电催化活性进行了研究。MXene是一种二维过渡金属碳化物，由于其高导电性、亲水性和丰富的表面官能团而被选择作为导电载体。这些特性增强了电子的快速传递，并为钒离子相互作用提供了一个可接近的表面。SnO2纳米颗粒具有催化活性和润湿性，均匀分布在MXene表面，有助于更好的氧化还原和电荷转移过程。与单个组分相比，该复合材料对VO2+/VO2+和V2+/V3+对的电催化活性均有所增强。MXene和SnO2的协同作用增强了离子扩散、电子传递和界面电荷转移。电池测试证实了更高的电解质性能和减少极化。在电流密度为100 mA/cm2时，能量效率达到85%，比裸电极提高了5%。这些发现表明，混合MXene和金属氧化物是为钒氧化还原液流电池制造高性能电催化剂的一种极好的技术。

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引用次数: 0

Boundary effect on the determination of the intralaminar fracture toughness of woven composite 机织复合材料层间断裂韧性测定中的边界效应

IF 7.1 2区材料科学 Q1 MATERIALS SCIENCE, COMPOSITES

Composite Structures

Pub Date : 2025-12-23 DOI: 10.1016/j.compstruct.2025.120004

Wushuai Liu , Jian Huang , Rui Liu , Chennian Shi , Wu Xu

In the existing literature, the boundary condition of a single-edge notch tensile (SENT) test is usually modeled as uniform displacement or uniform stress to calculate the intralaminar fracture toughness of composite materials. In this paper, it is observed that the boundary displacements obtained from digital image correlation (DIC) are non-uniform and dependent on the clamping pressure. A SENT finite element (FE) model with wedge grips is established to study the influence of clamping pressure on the displacement distribution. Considering the boundary effect, FE analysis with the boundary condition from DIC of the SENT test is applied to determine the fracture toughness resistance R-curve of woven composites. It is found that the fracture toughness obtained using uniform displacement or uniform stress as boundary conditions is quite different from that using the displacement condition from the DIC. The boundary condition from the DIC is strongly recommended for characterizing the fracture toughness of composite materials.

在现有文献中，单刃缺口拉伸（SENT）试验的边界条件通常建模为均匀位移或均匀应力来计算复合材料的层内断裂韧性。本文观察到由数字图像相关（DIC）得到的边界位移是不均匀的，并且依赖于夹紧压力。为了研究夹紧压力对位移分布的影响，建立了楔形夹紧的send有限元模型。考虑边界效应，采用基于send试验DIC边界条件的有限元分析方法，确定了机织复合材料的断裂韧性和抗断裂韧性r曲线。用均匀位移或均匀应力作为边界条件得到的断裂韧性与用DIC的位移条件得到的断裂韧性有很大的不同。DIC的边界条件被强烈推荐用于表征复合材料的断裂韧性。

引用次数: 0

Influence of boehmite nanoparticles on moisture absorption and temperature effects in GFRP used for wind turbine blades 薄水铝石纳米颗粒对风力涡轮机叶片用玻璃钢吸湿和温度效应的影响

IF 7.1 2区材料科学 Q1 MATERIALS SCIENCE, COMPOSITES

Composite Structures

Pub Date : 2025-12-23 DOI: 10.1016/j.compstruct.2025.120006

Maximilian Jux, Thorsten Mahrholz, Peter Wierach

While boehmite nanoparticle integration enhances GFRP mechanical performance under standard conditions, their behavior under environmental stressors is less understood. This study investigates the effect of moisture absorption and temperature on nanoparticle-reinforced GFRP. A wind power-proven epoxy resin was modified with 5 and 10 wt% taurine-modified boehmite nanoparticles using a three-roll mill. Appropriate processing parameters are identified using viscosity and DSC measurements. Nanomodified GFRP composites are prepared via Vacuum Assisted Resin Infusion (VARI). Furthermore, the influence of moisture and temperature on GFRP properties, considering particle content and layer thickness, was investigated. Therefore, samples are stored under hot-wet conditions (50 °C; 70 % RH) until water saturation. Tensile properties of saturated and dry samples are then evaluated at test temperatures between − 20 °C and + 60 °C. Rheological tests have shown that the viscosity increases more quickly with rising temperature and increasing particle content. At the same time, the initial viscosity drops and the pot life extends by increasing the temperature, particularly for the particle-reinforced resins. DSC measurements confirm that the investigated particle modification only has a small impact on the epoxy system’s cross-linking, while the addition of water leads to reduced cross-linking. Furthermore, the storage of GFRP samples under hot-wet conditions showed that particle modification leads to reduced moisture absorption, which, however, increases again with increasing particle content. Different mechanisms, particularly based on polarity and tortuosity effects, are discussed. The tensile tests reveal that storage under hot-wet conditions results in a decrease in secant modulus (up to 58 %), ultimate tensile strength (up to 53 %) and strain to failure (up to 62 %). This effect is more pronounced in materials with particle modification.

在标准条件下，薄水铝石纳米颗粒集成提高了GFRP的力学性能，但其在环境应力条件下的行为尚不清楚。研究了温度和吸湿性能对纳米颗粒增强玻璃钢的影响。用三辊磨机分别用5%和10%牛磺酸修饰的薄水铝石纳米颗粒对一种风力发电验证的环氧树脂进行了改性。适当的工艺参数确定使用粘度和DSC测量。采用真空辅助树脂注入（VARI）法制备了纳米改性GFRP复合材料。在考虑颗粒含量和层厚的情况下，研究了湿度和温度对GFRP性能的影响。因此，样品保存在湿热条件下（50°C; 70% RH），直到水饱和。然后在- 20°C和+ 60°C之间的测试温度下评估饱和和干燥样品的拉伸性能。流变试验表明，随着温度的升高和颗粒含量的增加，粘度的增加速度更快。同时，随着温度的升高，初始粘度下降，锅的寿命延长，特别是颗粒增强树脂。DSC测量证实，所研究的颗粒改性对环氧体系的交联影响很小，而水的加入会减少交联。此外，在热湿条件下储存的GFRP样品表明，颗粒改性导致吸湿率降低，但随着颗粒含量的增加，吸湿率再次增加。讨论了不同的机制，特别是基于极性和扭曲效应的机制。拉伸试验表明，在湿热条件下储存导致割线模量下降（高达58%），极限抗拉强度下降（高达53%）和破坏应变下降（高达62%）。这种效应在有颗粒改性的材料中更为明显。

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引用次数: 0

Yarn-carrier trajectory planning method of 3D rotary braiding for variable cross-section composite structure 变截面复合材料结构三维旋转编织纱线载体轨迹规划方法

IF 7.1 2区材料科学 Q1 MATERIALS SCIENCE, COMPOSITES

Composite Structures

Pub Date : 2025-12-23 DOI: 10.1016/j.compstruct.2025.119999

Xishuang Jing , Yuhang Ding , Jihao Ran , Fubao Xie , Chengyang Zhang , Siyu Chen

Three-dimensional (3D) braided composites hold great promise for engineering applications due to their superior mechanical performance. However, conventional braiding machines face challenges in producing preforms with variable cross-sectional geometries. This study proposes a trajectory planning framework for 3D braiding based on shortest carrier transfer paths. By discretizing the meshed geometric model of the preform into shape matrices, the method maps carrier positions and optimizes transfer paths under machine constraints, thereby ensuring smooth transitions and avoiding collisions. The framework is validated on diverse geometries, including tapered beams, tubular sections, and branched structures, confirming its adaptability to complex preforms. The structural fidelity of the braided preforms is validated through multi-color yarn visualization, while interlaminar shear strength (ILSS) tests demonstrate a 39.8% improvement over conventional resin transfer molding (RTM) components, attributed to enhanced yarn interlacing. The proposed approach has the potential to serve as an efficient and automated route for fabricating complex aerospace preforms with improved structural integrity.

三维（3D）编织复合材料由于其优越的力学性能，在工程应用中具有很大的前景。然而，传统的编织机在生产具有可变截面几何形状的预制品方面面临挑战。提出了一种基于最短载体传递路径的三维编织轨迹规划框架。该方法通过将预制件的网格化几何模型离散为形状矩阵，映射载体位置，并在机器约束下优化传递路径，从而保证平滑过渡和避免碰撞。该框架在不同的几何形状上进行了验证，包括锥形梁、管状截面和分支结构，证实了它对复杂预制体的适应性。通过多色纱线可视化验证了编织预制品的结构保真度，而层间剪切强度（ILSS）测试表明，由于增强了纱线的交错性，编织预制品比传统的树脂传递模塑（RTM）组件提高了39.8%。所提出的方法有可能作为一种高效和自动化的路线，用于制造具有改进结构完整性的复杂航空航天预制体。

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引用次数: 0