【新文速递】2024年7月9日复合材料SCI期刊最新文章

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今日更新：Composite Structures 2 篇，Composites Part A: Applied Science and Manufacturing 1 篇，Composites Part B: Engineering 1 篇，Composites Science and Technology 1 篇

Composite Structures

Susceptibility versus flexural stiffness in the stability of hybrid laminate columns with a rectangular cross section for a 1D model

Andrzej Teter, Zbigniew Kolakowski

doi:10.1016/j.compstruct.2024.118362

一维模型中矩形截面混合层压板柱稳定性中的敏感性与抗弯刚度关系

Hybrid columns of FGM/FML type with inhomogeneous transverse structure perpendicular to their length are discussed. After that, laminated columns with different layups of laminate plies are discussed, with focus put on the effect exerted by many coupling of the stiffness submatrix on the lowest eigenvalue load. All columns were simply supported The study uses three methods for determining the lowest eigenvalues. The first two are analytical beam methods (i.e. 1D modelling approaches) based on the use of the Euler-Bernoulli theory. The proposed 1D methods are a generalisation of the well-known approach of determining the lowest eigenloads of isotropic columns. The first approach is to solve the eigenproblem directly from the differential equation of the deflection line. The second approach assumes that the curvature of the beam depends on the susceptibility of the beam. This is a fundamental assumption in the bending theory of beams and thin plates. The third method is the FEM (3D shell approach) which is used for the verification of the previous calculations. A comparison of the obtained results showed that the proposed 1D (one-dimensional) approach based on the full susceptibility matrix, which is the inverse stiffness matrix was as accurate as the 3D (three-dimensional) FEM shell model. The relative difference does not exceed 3%. Second 1D approach based on the stiffness matrix yields many times unacceptable differences relative to the reference results obtained by the FEM method. This comparison clearly demonstrates that an approach based on the assumption that curvature is directly proportional to susceptibility in flexural composite structures produces accurate results for all types of coupling.The existing literature extensively explores the impacts of stiffness matrix elements on both the linear and non-linear stability of laminate columns. However, there is a notable absence of studies focusing on the influence of susceptibility. This crucial aspect has been overlooked in prior studies. The present paper endeavors to fill this gap by shedding light on the influence of susceptibility, thereby emphasizing its significance in the analysis of laminate column stability.

讨论了具有垂直于其长度的不均匀横向结构的 FGM/FML 型混合柱。随后，讨论了不同层叠层的层叠柱，重点是刚度子矩阵的许多耦合对最低特征值载荷的影响。研究采用三种方法确定最低特征值。前两种是基于欧拉-伯努利理论的梁分析方法（即一维建模方法）。拟议的一维方法是对确定各向同性柱最低特征荷载的著名方法的概括。第一种方法是直接根据挠度线微分方程求解特征问题。第二种方法假定梁的曲率取决于梁的敏感性。这是梁和薄板弯曲理论中的一个基本假设。第三种方法是有限元法（三维壳体法），用于验证之前的计算结果。对所得结果的比较表明，基于全易感矩阵（即反刚度矩阵）的拟议 1D（一维）方法与 3D （三维）有限元壳模型同样精确。相对差异不超过 3%。第二种基于刚度矩阵的一维方法与有限元方法得出的参考结果相比，产生了数倍的不可接受的差异。这一比较清楚地表明，基于曲率与挠性复合结构中的易感性成正比这一假设的方法可以为所有类型的耦合产生精确的结果。现有文献广泛探讨了刚度矩阵元素对层压柱线性和非线性稳定性的影响。然而，关于易感性影响的研究却明显不足。之前的研究忽略了这一重要方面。本文试图通过阐明易感性的影响来填补这一空白，从而强调易感性在层压支柱稳定性分析中的重要性。

Deflection and stress characteristics of single lap joint (adhesively bonded) theoretical analysis and experimental verification

Naveen Kumar Akkasali, Sandhyarani Biswas, Subrata Kumar Panda

doi:10.1016/j.compstruct.2024.118375

单搭接接头（粘合剂粘接）的挠度和应力特性理论分析与实验验证

The adhesively bonded single-lap joint strength is computed numerically and verified with the experiment. An ABAQUS model is prepared to analyze by adding the primary information, i.e., geometry, material properties, element, and solution type, including the boundary conditions. The model accuracy has been verified through two-step comparisons with published numerical deflection data and in-house experiments. The validated model is used to compute the energy-absorbing capacity better to understand lap joint strength. Further, the statistical analysis (variance-based sensitivity analysis) is conducted to measure the model output variability with the model input parameter. Additionally, the influences of geometry and property-dependent design parameters (layup schemes, loading position, adherend thickness ratio (L/t), and adhesive thickness ratio: (a/h), including the overlapping length (25, 30, 35, and 40 mm) are examined through several examples. The conclusions on the overlap length in bonded joints are that an increase in intact/lap length improves the joint stiffness and decreases the deflection. Similarly, a few insights on layer sequence (angle-ply) and shear stress thickness ratio are discussed in detail.

通过数值计算和实验验证了粘合单搭接接头的强度。通过添加主要信息（即几何形状、材料属性、元素和求解类型，包括边界条件），建立 ABAQUS 模型进行分析。通过与已公布的数值挠度数据和内部实验进行两步对比，验证了模型的准确性。经过验证的模型可用于计算能量吸收能力，从而更好地了解搭接强度。此外，还进行了统计分析（基于方差的敏感性分析），以测量模型输出与模型输入参数之间的变异性。此外，还通过几个实例研究了与几何形状和特性相关的设计参数（铺设方案、加载位置、粘合剂厚度比 (L/t) 和粘合剂厚度比：（a/h），包括重叠长度（25、30、35 和 40 毫米））的影响。关于粘接接头重叠长度的结论是，增加完整/重叠长度可提高接头刚度并减少挠度。同样，我们还详细讨论了关于层序（角层）和剪应力厚度比的一些见解。

Composites Part A: Applied Science and Manufacturing

Nanocellulose-assisted construction of multi-cavity structured Ti3C2Tx/melamine composite sponges for enhanced electromagnetic interference shielding

Daqiang Zhao, Xu Zhou, Tianhao Cui, Gui-Gen Wang

doi:10.1016/j.compositesa.2024.108347

纳米纤维素辅助构建用于增强电磁干扰屏蔽的多腔结构 Ti3C2Tx/melamine 复合海绵

The deposition of Ti3C2Tx nanosheets onto an ultralight melamine sponge (MS) holds great appeal for constructing mechanically robust and high-performance electromagnetic interference (EMI) shielding composites. However, the full potential of Ti3C2Tx materials for shielding performance is impeded by the insufficient affinity between Ti3C2Tx nanosheets and MS. Herein, with the assistance of cellulose nanofibers (CNF), large-sized single-layer Ti3C2Tx nanosheets were firmly attached to the MS skeleton and enveloped the pores. The obtained Ti3C2Tx/MS composite sponges exhibit a unique multi-cavity structure. Moreover, hydrophobic modification was applied to the composites through the use of two-component silane coupling agents. The silane-modified multi-cavity structured composite sponges demonstrate significant enhancements in conductivity, mechanical strength, and environmental stability. Particularly, the incorporation of 17 wt% CNF leads to a 29.3 dB increases in shielding efficiency (SE) for the composite sponge. The enhancement can be attributed to the high reflectance of electromagnetic waves due to the highly conductive Ti3C2Tx/CNF cavity-membranes, the multiple internal reflections within the multi-cavity structure, and the improved interfacial polarization loss capability facilitated by the abundance of MXene-CNF interfaces.

在超轻三聚氰胺海绵（MS）上沉积 Ti3C2Tx 纳米片材，对于构建机械坚固的高性能电磁干扰（EMI）屏蔽复合材料具有极大的吸引力。然而，由于 Ti3C2Tx 纳米片与三聚氰胺海绵之间的亲和力不足，阻碍了 Ti3C2Tx 材料屏蔽性能潜力的充分发挥。在此，在纤维素纳米纤维（CNF）的帮助下，大尺寸单层 Ti3C2Tx 纳米片被牢固地附着在 MS 骨架上，并包覆了孔隙。获得的 Ti3C2Tx/MS 复合海绵呈现出独特的多腔结构。此外，还使用双组分硅烷偶联剂对复合材料进行了疏水改性。硅烷改性的多腔结构复合海绵在导电性、机械强度和环境稳定性方面都有显著提高。特别是加入 17 wt% 的 CNF 后，复合海绵的屏蔽效率 (SE) 提高了 29.3 dB。这种增强可归因于高导电性 Ti3C2Tx/CNF 空腔膜带来的高电磁波反射率、多空腔结构内的多重内部反射以及大量 MXene-CNF 接口带来的更好的界面极化损耗能力。

Composites Part B: Engineering

Graphene at different scales to synergistically optimize the thermal and mechanical properties of CF/PPBESK composites

Bing Wang, Nan Li, Qingguang Bao, Shan Cheng, Jingyao Feng, Mengting Li, Ning Wang, Zaiyu Wang, Binlin Jiang, Lei Chen, Houquan Hong, Xigao Jian

doi:10.1016/j.compositesb.2024.111692

不同尺度的石墨烯协同优化 CF/PPBESK 复合材料的热性能和机械性能

This paper examined the impact of graphene's different scales on carbon fibre-reinforced thermoplastic composites' thermal and mechanical properties (CFRTPs). Experiments using a mixing design method with graphene content of large, medium, and small scales as variables, thermal conductivity (λ) and mechanical properties (flexural (F), compression (C), and tensile strength (T)) as response values. The thermal-mechanical properties of multi-component composites were analyzed and modelled to improve them. Graphene with different scales could effectively bridge and enhance heat flow transfer along the graphene thermal conductivity network, significantly improving the composite’s thermal conductivity. It was verified that the optimized composites exhibited excellent thermal conductivity (λ = 1.329 W/m·K), 140.3 % higher than that pure composite. Furthermore, the mechanical properties of the optimized composites saw significant enhancements, with flexural strength, compressive strength, and tensile strength increasing by 18.9 %, 22.8 %, and 13.2 %, respectively. Moreover, the optimized composite’s thermal properties and energy storage modulus were also notably improved.

本文研究了不同尺度的石墨烯对碳纤维增强热塑性复合材料热性能和机械性能（CFRTPs）的影响。实验采用混合设计法，以大、中、小尺度的石墨烯含量为变量，导热系数（λ）和机械性能（弯曲强度（F）、压缩强度（C）和拉伸强度（T））为响应值。对多组分复合材料的热机械性能进行了分析和建模，以改善其性能。不同尺度的石墨烯可以有效地架桥并增强热流沿石墨烯导热网络的传递，从而显著提高复合材料的导热性能。实验证明，优化后的复合材料具有优异的热导率（λ = 1.329 W/m-K），比纯复合材料高出 140.3%。此外，优化复合材料的机械性能也有显著提高，抗折强度、抗压强度和抗拉强度分别提高了 18.9%、22.8% 和 13.2%。此外，优化复合材料的热性能和储能模量也有明显改善。

Composites Science and Technology

Performance enhancement of silica filled natural rubber nanocomposites using organic deep eutectic solvent

Qiao Li, Hongda Meng, Yihu Song, Qiang Zheng

doi:10.1016/j.compscitech.2024.110744

使用有机深共晶溶剂提高二氧化硅填充天然橡胶纳米复合材料的性能

Silica is an important filler of “green tires” while its dispersion in the aid of silane coupling agents emits volatile organic compounds during rubber compounding and its invariably agglomeration in nonpolar rubber matrices enhances strain softening. Herein a highly active deep eutectic solvent (DES), using stearic acid as hydrogen bond donor and tetrabutylammonium chloride as hydrogen bond acceptor, is used to tailor reinforcement and softening behaviors and to replace the silane coupling agents for preparing volatile organic compounds-free nanocomposites. The results show that DES can regulate the crosslinking network structure of rubber matrix and accelerate the vulcanization by reacting with non-rubber components in natural rubber (NR) and by improving the proportion of disulfidic linkage. Furthermore, DES is able to improve the dispersion of silica, crosslinking density of NR and the interfacial interaction between silica and NR, and slow down the thermo-oxidative aging behavior. It could also weaken the damping and softening accompanying Mullins effect for the nanocomposites vulcanizates at high strains. In comparison with silane, DES endows the nanocomposites with superior vulcanization and mechanical properties, providing guides to mediate the reinforcement and strain softening behaviors and manufacture high-performance “green tires” in an energy-efficient approach.

二氧化硅是 "绿色轮胎 "的重要填充物，但在硅烷偶联剂的帮助下，二氧化硅的分散会在橡胶混炼过程中释放出挥发性有机化合物，而且二氧化硅在非极性橡胶基质中的聚集会增强应变软化。在此，以硬脂酸为氢键供体、四丁基氯化铵为氢键受体的高活性深共晶溶剂（DES）被用于定制补强和软化行为，并替代硅烷偶联剂制备无挥发性有机化合物的纳米复合材料。研究结果表明，DES 可以调节橡胶基体的交联网络结构，并通过与天然橡胶（NR）中的非橡胶成分发生反应以及提高二硫键的比例来加速硫化。此外，DES 还能改善二氧化硅的分散性、天然橡胶的交联密度以及二氧化硅与天然橡胶之间的界面相互作用，并减缓热氧化老化行为。它还能减弱纳米复合材料硫化胶在高应变下伴随 Mullins 效应产生的阻尼和软化。与硅烷相比，DES 使纳米复合材料具有更优越的硫化性能和机械性能，为调解补强和应变软化行为以及以节能方式制造高性能 "绿色轮胎 "提供了指导。

来源：复合材料力学仿真Composites FEM

【新文速递】2024年7月14日复合材料SCI期刊最新文章

今日更新：Composites Part B: Engineering 3 篇，Composites Science and Technology 2 篇Composites Part B: EngineeringDeveloping Heat-Conductive Concrete with Graphite-Modified Recycled AggregatesChen Chen, Xin Liu, Zhaolong Liu, Lijing Shao, Honglei Chang, Qi Liu, Changwen Miao, Pan Fengdoi:10.1016/j.compositesb.2024.111721石墨改性再生骨料导热混凝土的研制This study tackles temperature-induced cracks in contemporary concrete by addressing their low thermal conductivity. Heat-conductive concrete was developed by using graphite-modified recycled coarse aggregates. Through thorough evaluation of coating methods and aggregate types, we enhance thermal conductivity of recycled aggregates by up to 86% while improving apparent density, water absorption, and crushing value. Employing a one-pot method (Method B) with the graphite to cement ratio of 1:1 establishes an efficient thermal pathway within concrete, resulting in a significant 1.9-fold increase in thermal conductivity without compromising mechanical properties. Advanced imaging techniques and simulations confirm the pivotal role of this pathway in enhancing thermal properties, offering a cost-effective, eco-friendly solution for sustainable construction.本研究通过解决当代混凝土的低导热性来解决温度引起的裂缝。采用石墨改性再生粗骨料研制了导热混凝土。通过对涂层方法和骨料类型的全面评估，我们将再生骨料的导热性提高了86%，同时改善了表观密度、吸水率和破碎值。采用一锅法(方法B)，石墨与水泥的比例为1:1，在混凝土内部建立了有效的热通道，在不影响机械性能的情况下，导热系数显著提高了1.9倍。先进的成像技术和模拟证实了这一途径在提高热性能方面的关键作用，为可持续建筑提供了经济高效、环保的解决方案。Quantitative characterization of bubble stability of foam concrete throughout extrusion process: from yield stress, viscosity and surface tension point of viewChao Liu, Zedi Zhang, Zijian Jia, Ruilin Cao, Wei Wang, Nemkumar Banthia, Chun Chen, Yuanliang Xiong, Yu Chen, Yamei Zhangdoi:10.1016/j.compositesb.2024.111724泡沫混凝土在挤压过程中泡稳定性的定量表征:从屈服应力、粘度和表面张力的角度Foam concrete (FC) is suitable to be used as printing ink for drones in extreme environment because of its light weight, it can reduce the load of drones and improve printing efficiency. Furthermore, since the FC density and thermal insulation performance can be flexibly changed by changing the bubble content, it can be used to print functional gradient components and special-shaped insulation walls. The stability of bubbles is crucial as it directly impacts the performance of 3D printed FC (3DPFC). Here, we examined the bubble destabilization and deformation of FC throughout the mixing process, resting period prior to extrusion, and extrusion process based on three parameters, i.e., yield stress, viscosity, and surface tension. The results indicate that increasing the yield stress from 1406 Pa to 13379 Pa of the precursor leads to a decrease in bubble volume fraction after mixing from 38.26% to 27.24%, while increasing viscosity from 2.16 Pa·s to 6.65 Pa·s and decreasing surface tension from 72.4 mN/m to 33.5 mN/m are favorable for improving the sphericity of bubbles with the diameter between 300-800 μm in FC. In the resting stage, the yield stress of the interstitial paste is the primary factor controlling bubble stability. When the initial yield stress of the equivalent interstitial paste is 5212 Pa, the bubble volume fraction decreases by only 0.8% within 60 min. During extrusion, high yield stress leading to bubble deformation and instability, whereas viscosity and pore solution surface tension act as sources of bubble compression resistance. There exists a suitable diameter interval for bubble pressure-bearing limit under different paste environment during extrusion.泡沫混凝土(FC)重量轻，适合作为无人机在极端环境下的打印油墨，可以减轻无人机的负荷，提高打印效率。此外，由于可以通过改变气泡含量来灵活改变FC密度和保温性能，因此可以用于打印功能梯度组件和异形保温墙。气泡的稳定性是影响3D打印FC (3DPFC)性能的关键因素。在这里，我们基于屈服应力、粘度和表面张力三个参数，研究了FC在混合过程、挤出前休息时间和挤出过程中的气泡失稳和变形。结果表明:将前驱体的屈服应力从1406 Pa提高到13379 Pa，混合后气泡体积分数从38.26%降低到27.24%;将黏度从2.16 Pa·s提高到6.65 Pa·s，表面张力从72.4 mN/m降低到33.5 mN/m，有利于提高FC中300 ~ 800 μm直径气泡的球形度。静息阶段，间隙膏体的屈服应力是控制气泡稳定性的主要因素。当等效间隙体初始屈服应力为5212 Pa时，60 min内气泡体积分数仅下降0.8%。挤压过程中，高屈服应力导致气泡变形和不稳定，而粘度和孔溶液表面张力是气泡压缩阻力的来源。在不同的膏体挤出环境下，存在合适的气泡承压极限直径区间。Bio-based epoxy resin demonstrating high breakdown strength and low dielectric loss via intrinsic molecular charge traps constructionKerong Yang, Jinyue Dai, Weiwei Zhao, Shuaipeng Wang, Xiaoqing Liudoi:10.1016/j.compositesb.2024.111728 生物基环氧树脂具有高击穿强度和低介电损耗通过本征分子电荷陷阱的结构In the ultra-high voltage, ultra-high capacity and high frequency energy systems, epoxy-based dielectric materials demonstrating high breakdown strength and low dielectric loss are urgently needed. This work reports a strategy to modulate the charge trap depth in bio-based epoxy dielectric materials by tailoring the local molecular chain structures, ultimately leading to the significant suppression of high-field conductivity and dielectric loss. With the introduction of octa (dimethylsiloxy)octasilsiloxane (POSS) as the intrinsic molecular charge traps, our synthesized epoxy dielectric material exhibits a high breakdown strength of Eb-DC = 81.5 kV/mm, 37 % higher than the traditional bisphenol A epoxy resin (DGEBA), and low dielectric loss of tan δ = 0.0022, 45 % lower than that DGEBA. Furthermore, simulation results give the structure-property relationships, guiding the molecular design. Specifically, the dielectric properties are positively correlated with the LUMO energy difference and charge separation index of the polymer molecular chains. This work provides a promising pathway to enhance the dielectric properties of polymers by building intrinsic molecular charge traps, which is prospective for practical electronics and electrical power systems.在超高电压、超大容量和高频率能源系统中，迫切需要具有高击穿强度和低介电损耗的环氧基介电材料。本研究报告介绍了一种通过调整局部分子链结构来调节生物基环氧介电材料电荷阱深度的策略，最终显著抑制了高场电导率和介电损耗。通过引入八（二甲基硅氧烷）八硅氧烷（POSS）作为本征分子电荷阱，我们合成的环氧介电材料表现出较高的击穿强度（Eb-DC = 81.5 kV/mm），比传统的双酚 A 环氧树脂（DGEBA）高出 37%，介电损耗较低（tan δ = 0.0022），比 DGEBA 低 45%。此外，模拟结果还给出了结构-性能关系，为分子设计提供了指导。具体来说，介电性能与聚合物分子链的 LUMO 能量差和电荷分离指数呈正相关。这项工作为通过构建固有分子电荷陷阱来增强聚合物的介电性能提供了一条很有前景的途径，在实用电子和电力系统中具有广阔的应用前景。Composites Science and TechnologyInterfacial debonding and cracking in a solid propellant composite under uniaxial tension: An in situ synchrotron X-ray tomography studyG.D. Lai, L.P. Sang, Y.L. Bian, H.L. Xie, J.H. Liu, H.W. Chaidoi:10.1016/j.compscitech.2024.110743 单轴拉伸作用下固体推进剂复合材料界面脱粘和开裂:原位同步加速器x射线断层成像研究Deformation and fracture of a hydroxyl-terminated polybutadiene (HTPB)/ammonium perchlorate (AP)/aluminum solid propellant under quasi-static tensile loading are investigated by in situ synchrotron X-ray micro computed tomography (CT) and CT-image-based finite element method (FEM) modeling. Bulk stress–strain curve of the solid propellant, and the evolution of particle morphology, and mesoscale strain and particle displacement fields are obtained. Based on tracking and statistics, an automated analytical method is proposed to analyze the relationship between microcrack nucleation and initial structure. The AP particles undergo negligible deformation and orientation changes during tensile loading. Microcracks are mainly nucleated via tension-induced debonding at the maximum surface curvature of the AP particles, and propagate along the curvature gradient around AP particles. Larger AP particles are more prone to debond, and Al particles play a negligible role in deformation and fracture.采用原位同步加速器x射线微计算机断层扫描(CT)和基于CT图像的有限元方法(FEM)模拟研究了端羟基聚丁二烯(HTPB)/高氯酸铵(AP)/铝固体推进剂在准静态拉伸载荷作用下的变形和断裂。得到了固体推进剂的体应力-应变曲线、颗粒形态演化、中尺度应变场和颗粒位移场。提出了一种基于跟踪和统计的微裂纹形核与初始结构关系的自动分析方法。在拉伸加载过程中，AP颗粒的变形和取向变化可以忽略不计。微裂纹主要在AP颗粒的最大表面曲率处通过张力诱导脱粘成核，并沿AP颗粒周围的曲率梯度扩展。较大的AP颗粒更容易脱落，而Al颗粒对变形和断裂的作用可以忽略不计。Engineered Living Composite MaterialsI.H.M.S. Nettersheim, N.S. Guevara Sotelo, J.C. Verdonk, K. Masaniadoi:10.1016/j.compscitech.2024.110758 工程活体复合材料Since the inception of fibre-reinforced composite materials, they have been widely acknowledged for their unparalleled weight-to-performance ratio. Nonetheless, concerns are escalating regarding the environmental impact of these materials amidst global warming and pollution. This perspective explores a ground-breaking shift towards harnessing living organisms to produce composite materials. Living composites not only offer sustainable, carbon-capturing alternatives but also afford an unprecedented level of control over shape and anisotropy. Recent advancements in biology, particularly genetic engineering and sequencing, have provided unprecedented control over living organisms. Coupled with ever-evolving additive manufacturing techniques, these breakthroughs enable the construction of engineered living materials from the ground up. This perspective explores the key factors propelling the emergence of engineered living materials for structural applications and delves into the capabilities of living organisms that can be harnessed for creating functional materials, including harvesting energy, forming structures, sensing and adapting, and growing and remodelling. Incorporating living organisms in composite construction can revolutionise manufacturing for renewable and sustainable composite materials, unlocking previously unattainable functionalities.自纤维增强复合材料问世以来，它们以其无与伦比的重量性能比而得到广泛认可。然而，在全球变暖和环境污染的背景下，人们对这些材料对环境的影响的担忧正在升级。这一观点探索了利用生物体生产复合材料的突破性转变。活体复合材料不仅提供了可持续的碳捕获替代品，而且还提供了前所未有的形状和各向异性控制水平。生物学的最新进展，特别是基因工程和测序，已经提供了对生物体前所未有的控制。再加上不断发展的增材制造技术，这些突破使工程生物材料的构建成为可能。这一观点探讨了推动结构应用工程生物材料出现的关键因素，并深入研究了可以用于创造功能材料的生物体的能力，包括收集能量、形成结构、感知和适应、生长和重塑。将生物体纳入复合材料结构可以彻底改变可再生和可持续复合材料的制造，解锁以前无法实现的功能。来源：复合材料力学仿真Composites FEM