今日更新：Composite Structures 7 篇，Composites Part B: Engineering 8 篇，Composites Science and Technology 4 篇

Composite Structures

Dynamic hydroelasticity of composite appendages with reverse-mode algorithmic differentiation

Galen W. Ng, Eirikur Jonsson, Sicheng He, Joaquim R.R.A. Martins

doi:10.1016/j.compstruct.2024.118367

基于反模算法微分的复合附件动态水弹性

Composite materials enable the tailoring of load-dependent, passive, shape adaptation because of the directional stiffness of the fibers. However, excessive flow-induced vibrations and dynamic instabilities represent a design challenge for composite marine appendages. We develop DCFoil, a dynamic composite foil solver that uses one-dimensional models—composite beam elements and unsteady lifting line theory—to perform static and dynamic frequency domain analysis. The program is differentiated to provide derivatives of an aggregated flutter function with respect to design variables. The flutter function characterizes dynamic hydroelastic stability. We apply the solver to investigate the hydroelastic performance of a composite fin bulb keel based on the IMOCA 60 class of racing yachts, which were reported to have flutter problems. Based on the derivatives computed for this bulb keel, we found that the foil thickness has the most significant impact on flutter speed. This work shows both the development of and utility of a program with flutter derivatives for flexible composite marine appendage design.

由于纤维的定向刚度，复合材料可以实现负载依赖、被动、形状适应的剪裁。然而，过度的流激振动和动力不稳定性是复合海洋附件的设计挑战。我们开发了DCFoil，一个动态复合箔求解器，使用一维模型-复合梁单元和非定常升力线理论-进行静态和动态频域分析。该程序是微分的，以提供关于设计变量的总颤振函数的导数。颤振函数表征了动态水弹性稳定性。本文应用该求解器对IMOCA 60级赛艇复合材料鳍球龙骨的水弹性性能进行了研究，该赛艇存在颤振问题。通过计算球泡龙骨的导数，发现翼板厚度对颤振速度的影响最为显著。这一工作展示了具有颤振导数的柔性海洋复合附件设计程序的发展和实用性。

Minimal mass optimization of tensegrity torsional structures

Jingfeng He, Yihang Wang, Xin Li, Hongzhou Jiang, Hangchen Xie, Yizi Zhou

doi:10.1016/j.compstruct.2024.118376

张拉整体扭转结构的最小质量优化

The advantage of high strength-to-mass ratio renders tensegrity structures suitable for application as lightweight structures. Therefore, the minimal mass optimization problem is one of the focal points in the research of tensegrity structures. Various minimal mass optimization configurations have been proposed for different types of loads. In this paper, we will continue this topic to deal with the minimal mass optimization problem of the tensegrity structure under torsional loads. The inspiration for this study stems from the constant radial angle feature of Michell structures, which is also present in the logarithmic spiral. By employing inverse stereographic projection with conformality, the logarithmic spiral can be mapped onto the sphere , the angle between the curve and the lines of latitude remains constant. On this basis, a type of tensegrity sphere structure combining the spherical logarithmic spiral and DHT (Double Helix Tensegrity) topology is proposed. Compared to the other two spheres with identical topology, the proposed tensegrity sphere structure significantly reduces the minimal mass under torsional loads. Furthermore, we have observed that when logarithmic spiral curves with opposite chirality are orthogonal, the optimal solution with minimal mass occurs. These findings demonstrate the potential of the combination of logarithmic spirals and conformal transformations, and positive effect of the orthogonal arrangement of members for mass optimization of tensegrity structures.

高强度质量比的优点使得张拉整体结构适合作为轻量化结构应用。因此，最小质量优化问题是张拉整体结构研究的热点之一。针对不同类型的载荷，提出了不同的最小质量优化配置。在本文中，我们将继续这一主题来处理扭转载荷下张拉整体结构的最小质量优化问题。本研究的灵感来自米歇尔结构的恒定径向角特征，这也存在于对数螺旋中。采用共形逆立体投影法，将对数螺旋线映射到球体上，曲线与纬线夹角保持不变。在此基础上，提出了一种结合球面对数螺旋和DHT(双螺旋张拉整体)拓扑结构的张拉整体球面结构。与具有相同拓扑结构的其他两种球体相比，所提出的张拉整体球体结构显著降低了扭转载荷下的最小质量。此外，我们还观察到，当具有相反手性的对数螺旋曲线正交时，出现了质量最小的最优解。这些发现证明了对数螺旋和保形变换相结合的潜力，以及构件正交布置对张拉整体结构质量优化的积极作用。

Fabrication and failure mechanisms of ultralight all-CFRP sandwich cylinders under axial compression

Ziqi Chu, Ruochen Wang, Shubin Tian, Chengyang Wang, Linzhi Wu, Qianqian Wu, Guocai Yu

doi:10.1016/j.compstruct.2024.118386

超轻全cfrp夹芯筒轴压破坏机理研究

Ultralight all-CFRP honeycomb sandwich cylinders were fabricated using a stretching process. Subsequently, critical failure loads corresponding to five typical failure modes of the sandwich cylinders under axial compression were obtained through theoretical derivation. Three-dimensional failure mechanism maps were generated, which intuitively revealed the influence of the dimensionless parameters on structural failure. The panel thickness was selected as a variable, and quasi-static axial compressive tests were performed on the sandwich cylinders. Two failure modes, intracellular buckling and face crushing, were observed, which is consistent with theory. The experimental results were analysed and discussed systematically. The ultralight all-CFRP honeycomb sandwich cylinders were compared with existing cylinders to reveal their bearing advantages. The established failure mechanism maps provide guidance for the preparation and optimisation of honeycomb sandwich cylinders. Compared with the traditional fabrication processes of honeycomb cores, the novel stretching process is expected to achieve mass production, which is helpful to provide technical support for the lightweight manufacturing of aerospace structural components.

采用拉伸工艺制备了超轻全cfrp蜂窝夹层圆柱体。随后，通过理论推导得到了夹层柱在轴压作用下的五种典型失效模式对应的临界失效载荷。生成了三维破坏机理图，直观地揭示了无量纲参数对结构破坏的影响。选取面板厚度为变量，对夹芯筒进行准静态轴压试验。观察到胞内屈曲和面压两种破坏模式，与理论一致。对实验结果进行了系统的分析和讨论。通过与现有超轻全cfrp蜂窝夹芯筒的对比，揭示了其承载优势。所建立的失效机理图为蜂窝夹芯筒的制备和优化提供了指导。与传统的蜂窝芯制造工艺相比，新型拉伸工艺有望实现量产，为航空结构件轻量化制造提供技术支持。

Multi-scale investigation on the interfacial behavior of between NC and UHPC in flexural members considering influence of the interface morphology

Boshan Zhang, Jiangjiang Yu, Weizhen Chen, Hang Liu, Heng Li

doi:10.1016/j.compstruct.2024.118388

考虑界面形貌影响的受弯构件NC与UHPC界面行为的多尺度研究

To study the interfacial behavior between NC (normal concrete) and UHPC (ultra-high performance concrete) in composite flexural members, a multi-scale numerical simulation framework was proposed, and then verified by three-point bending tests conducted on RC (reinforced concrete)-UHPC composite girders, considering different interface morphologies. The numerical model of a RC-UHPC girder based on this method can take into account the influence of the material mesoscale components as well as interfacial mesoscale morphology on the mechanical behavior. The results indicate that the damage and failure at the NC-UHPC interface of a flexural element is controlled by the horizontal shear. The interface roughness has positive effects on both the interfacial performance and the mechanical performance of a composite girder. When the root mean square roughness increases from 0.2 mm to 4.5 mm, the interface shear strength grows from 2.04 MPa to 5.20 MPa by 2.55 times, and the peak load applied to the girder grows from 197.9 kN to 239.3 kN by 1.21 times. The relationship between the resistance of a composite girder and the interfacial shear strength/ interface roughness could be described by the exponential function/ linear function.

为了研究NC(普通混凝土)与UHPC(超高性能混凝土)复合受弯构件之间的界面行为，提出了一种多尺度数值模拟框架，并在考虑不同界面形态的RC(钢筋混凝土)-UHPC复合梁上进行了三点弯曲试验验证。基于该方法的RC-UHPC梁数值模型可以考虑材料细观分量和界面细观形貌对梁力学行为的影响。结果表明:受弯单元NC-UHPC界面破坏破坏受水平剪切控制;界面粗糙度对复合梁的界面性能和力学性能都有积极的影响。当均方根粗糙度从0.2 mm增加到4.5 mm时，界面抗剪强度从2.04 MPa增加到5.20 MPa，增加了2.55倍;梁所受峰值荷载从197.9 kN增加到239.3 kN，增加了1.21倍。组合梁的阻力与界面抗剪强度/界面粗糙度之间的关系可以用指数函数/线性函数来描述。

Study on the composite compatibility and interfacial properties of excess sulfate phosphogypsum cementing system to OPC and CS¯A

Gaoshang Ouyang, Tao Sun, Yunhua Guo, Dong Xu, Juntu He, Lin Tang, Shiwei Long

doi:10.1016/j.compstruct.2024.118389

过量硫酸盐磷石膏胶结体系与 OPC 和 CS¯A 的复合相容性和界面性能研究

Releasable sulfate contained in the Excess Sulfate Phosphogypsum Cementing System (ESPCS) potentially degrades interfaces when contacted with conventional cements, raising compatibility concerns. This work evaluated fresh connection, adhesion, and aggregate embedment of ESPCS to ordinary Portland cement (OPC) and Calcium sulfoaluminate cement (CS¯A), with mechanical and interfacial properties studied. Results indicate the discrepancy in hydration properties gives Excess-sulfate Phosphogypsum Slag Cement (EPSC) uncoordinated expansion to OPC, followed by cracks (95 μm) generation. Meanwhile, expansive ettringite forms in the interface due to bleeding sulfate-rich water concentration, thus leaving a porous contact zone (1240 μm, 11.29%) and resultant flexural strength reduction of OPC-EPSC mortar (by >36 %). Conversely, EPSC and CS¯A are close in phase assemblages, resulting in compact interface and higher bond strength. Incorporating the Phosphogypsum-based Cold Bonded Aggregates (PCBAs) into OPC induces the interfacial ettringite formation-sulfate attack by internal curing water, yielding the worst composite performance, i.e., the lowest 360 d compressive strength (38.8 MPa) of concrete OPCC, lower than EPSCC (48.6 MPa) and CS¯AC (50.3 MPa). ESPCS is more compatible to CS¯A than OPC which is advised against exposing directly with ESPCS. This work helps specify composite feasibility and conditions of ESPCS with typical cement composites.

过硫酸盐磷石膏固结体系（ESPCS）中所含的可释放硫酸盐在与传统水泥接触时可能会使界面降解，从而引发兼容性问题。这项工作评估了过硫酸盐磷石膏固结体系与普通波特兰水泥（OPC）和硫铝酸钙水泥（CS¯A）的新鲜连接、粘附和骨料嵌入，并研究了机械和界面特性。结果表明，水化特性的差异导致硫酸盐磷石膏矿渣水泥（ESPC）与普通硅酸盐水泥（OPC）不协调膨胀，继而产生裂缝（95 μm）。同时，由于富含硫酸盐的水浓度的渗出，在界面上形成了膨胀性乙丁质岩，从而留下了多孔接触区（1240 μm，11.29%），导致 OPC-EPSC 砂浆的抗折强度降低（大于 36%）。相反，EPSC 和 CS¯A 的相组合很接近，因此界面紧凑，粘结强度更高。在 OPC 中加入磷石膏基冷粘结骨料（PCBAs）会诱发界面蚀变体的形成--内部养护水的硫酸盐侵蚀，从而产生最差的复合性能，即混凝土 OPCC 的 360 d 抗压强度最低（38.8 MPa），低于 EPSCC（48.6 MPa）和 CS¯AC（50.3 MPa）。与 OPC 相比，ESPCS 与 CS¯A 的相容性更好，建议不要直接使用 ESPCS。这项工作有助于明确 ESPCS 与典型水泥复合材料的复合可行性和条件。

Innovation in hierarchical metal organic framework derivatives toward electromagnetic wave absorption

Quyen Vu Thi, Hui Ling Tan, Karen Yuanting Tang, Jerry Zhi Xiong Heng, Xian Jun Loh, Enyi Ye, Daewon Sohn, Vinh Xuan Truong

doi:10.1016/j.compstruct.2024.118390

面向电磁波吸收的分层金属有机框架衍生物的创新

There is an urgent global demand for electromagnetic waves (EMWs) attenuation to eradicate electromagnetic pollution, which has become increasing prevalent within the last few decades. A promising approach to address such an issue is the application of metal–organic frameworks (MOFs) materials, taking advantage of their broad bandwidth, outstanding attenuation capability, ultrahigh porosity, ultra-low weight, and ease of processing. MOFs chemical structures can be readily tuned using the wide range of metals and ligands, enabling extensive tuning of their properties for applications in electromagnetic attenuation. In this review, we first summarize the fundamental theory of EMWs absorption. Subsequently, we discuss the recent progress on designing MOFs-based absorbing materials, with a focus on their key characteristics in EMWs attenuation. While MOF-based absorbers have been dominantly prepared by pyrolysis method, emerging approaches for the fabrication of MOF derived composites, such as self-assembling MOF-MXene, are also discussed. Existing drawbacks on current MOFs-derived materials are further identified. Addressing these drawbacks are critical for the development of effective MOFs-based absorbers for EMWs attenuation.

在过去的几十年里，全球对电磁波(EMWs)衰减的需求日益迫切，以消除电磁污染。解决这一问题的一个很有希望的方法是应用金属有机框架(mof)材料，利用其宽带宽、出色的衰减能力、超高孔隙率、超低重量和易于加工的优势。mof的化学结构可以很容易地使用各种金属和配体进行调整，从而可以广泛地调整其在电磁衰减中的应用。本文首先综述了电磁辐射吸收的基本理论。随后，我们讨论了基于mofs的吸波材料设计的最新进展，重点讨论了它们在emw衰减中的关键特性。虽然MOF基吸收剂主要是通过热解方法制备的，但新兴的MOF衍生复合材料的制备方法，如自组装MOF- mxene，也被讨论。进一步指出了目前mofs衍生材料存在的缺陷。解决这些缺点对于开发有效的基于mofs的emw衰减吸收剂至关重要。

A review on the analytical and numerical models for ballistic limit of fiber-reinforced composites

Chaonan Cong, Wenqing Zhu, Junjie Liu, Xiaoding Wei

doi:10.1016/j.compstruct.2024.118392

纤维增强复合材料弹道极限分析与数值模型研究进展

The fiber-reinforced polymer (FRP) composites have been widely used as bullet-proof materials due to their low specific gravity, high specific strength and stiffness, and excellent impact resistance. A comprehensive understanding of the energy absorption of the FRP composites during impact and penetration and accurate prediction of the ballistic limits of the FRP composites may provide valuable guidance for designing bullet-proof composites. In this review paper, various analytical and numerical research on the ballistic limits of FRP composites are outlined. Besides, the influences of various factors such as component properties and microstructure of FRP composites and impactor characteristics on the ballistic limits of FRP composites are discussed. We focus on introducing new methods and ideas that provide guidance for the design of advanced bullet-proof composites.

纤维增强聚合物(FRP)复合材料具有比重低、比强度和比刚度高、抗冲击性能优异等优点，被广泛应用于防弹材料。全面了解FRP复合材料在冲击和侵彻过程中的能量吸收，准确预测FRP复合材料的弹道极限，可为设计防弹复合材料提供有价值的指导。本文综述了各种关于FRP复合材料弹道极限的分析和数值研究。此外，还讨论了玻璃钢复合材料的构件性能、微观结构和冲击器特性等因素对玻璃钢复合材料弹道极限的影响。我们的重点是引入新的方法和思路，为先进的防弹复合材料的设计提供指导。

Composites Part B: Engineering

Advanced bifunctional bionic neural network-like architecture constructed by multi-scale carbon nanotubes nanocomposites for enhanced microwave absorption

Shuaizhen Li, Tianwen Xie, Lin Ma, Bo Li, Daheng Liu, Nan Huang, Wei Liu, Bing Li, Zhigang Gai, Xin Jiang, Song Ma, Zhidong Zhang

doi:10.1016/j.compositesb.2024.111714

基于多尺度碳纳米管纳米复合材料构建的新型双功能仿生神经网络结构

Accompanied with challenging to develop bifunctional microwave absorbers to enhance the environmental adaptability and survivability of electromagnetic devices in harsh environment, a three-dimensional (3D) hierarchical bionic neural network-like architectures decorated multi-scale Ni3Fe@N-doped carbon nanotube composites (Ni3Fe@NCNT@CF) were innovatively designed and constructed to realize the integration of microwave absorption and corrosion protection. The optimal Ni3Fe@NCNT@CF demonstrates competitive microwave absorption with a minimum reflection loss of −51.5 dB and a maximum effective absorption bandwidth (EAB) of 6.4 GHz at 10 wt%, due to superior interlinked conductive channels (with dominant and adjustable conduction loss) and magnetic-dielectric matching of the 3D hierarchical bionic neural network. A reliable anti-corrosion performance is further exhibited to show ultra-low corrosion current density ∼10-8 A·cm-2 after 30 days of immersion in corrosive medium, owing to the physical shield provided by the impermeable and inert CNT shells. Our findings may provide design inspiration of versatile microwave materials for applications in complicated environments.

为了提高电磁器件在恶劣环境下的环境适应性和生存能力，双功能微波吸收器的开发面临挑战，创新设计并构建了一种装饰多尺度Ni3Fe@N-doped碳纳米管复合材料(Ni3Fe@NCNT@CF)的三维(3D)分层仿生神经网络结构，实现了微波吸收与防腐的一体化。最佳Ni3Fe@NCNT@CF表现出竞争微波吸收，最小反射损耗为- 51.5 dB，最大有效吸收带宽(EAB)在10 wt%时为6.4 GHz，这是由于优越的相互连接的导电通道(具有主导和可调的传导损耗)和三维分层仿生神经网络的磁介质匹配。由于碳纳米管外壳的不渗透和惰性提供了物理屏蔽，在腐蚀介质中浸泡30天后，碳纳米管具有可靠的抗腐蚀性能，显示出超低的腐蚀电流密度~ 10-8 A·cm-2。本研究结果可为复杂环境下多用途微波材料的设计提供启示。

Novel application of ground penetrating radar for damage detection in thick FRP composites

James A. Quinn, Ourania Patsia, Antonios Giannopoulos, Conchúr M. Ó Brádaigh, Edward D. McCarthy

doi:10.1016/j.compositesb.2024.111716

探地雷达在厚FRP复合材料损伤检测中的新应用

This paper presents the first successful application of ground penetrating radar (GPR) to the inspection of thick ( ≥ 100 mm) fiber-reinforced composites. These thick composites are found in wind/tidal turbine blades and composite-hulled ships, where sufficient non-destructive testing (NDT) remains challenging. Polyester-glass specimens, ranging in thickness from 100 to 120 mm, were created with delamination-mimicking damage. Specimen thickness, damage depth location, antenna orientation and damage dryness were the test variables. Finite-difference time-domain simulations indicated the method’s feasibility, and experimental results confirmed these findings. GPR effectively detected and precisely located dry, in-plane damage, with increased detectability for water-filled damage due to the enhanced contrast of electrical properties that creates the damage response in the signal. This capability is particularly advantageous for marine composites, where extensive damage may lead to water ingress. In a comparison with an ultrasonic inspection, GPR proved superior for the thicker composites ( ≥ 100 mm). As the first successful application of GPR to composite structures, these findings significantly advance the field of NDT of these materials.

本文介绍了探地雷达(GPR)在厚(≥100mm)纤维增强复合材料检测中的首次成功应用。这些厚复合材料被用于风力/潮汐涡轮机叶片和复合船体船舶，在这些领域，充分的无损检测(NDT)仍然具有挑战性。聚酯玻璃样品的厚度从100到120毫米不等，具有分层模拟损伤。试件厚度、损伤深度位置、天线方向和损伤干燥度为试验变量。时域有限差分仿真验证了该方法的可行性，实验结果也证实了上述结论。GPR可以有效地检测和精确定位干燥的、平面内的损伤，由于增强了电信号中产生损伤响应的电性能对比，因此可以提高对充满水的损伤的可探测性。这种能力对于海洋复合材料尤其有利，因为海洋复合材料的大面积损坏可能导致进水。与超声波检测相比，探地雷达检测对较厚的复合材料(≥100 mm)更有利。作为探地雷达技术在复合材料结构中的首次成功应用，这一发现对复合材料无损检测领域具有重要的推动作用。

Lightweight Silicon and Glass Composites with Submicron Viscoelastic Interlayers and Unconventional Combinations of Stiffness and Damping

Ioanna Ch. Tsimouri, Walter Caseri, Peter J. Hine, Andrei A. Gusev

doi:10.1016/j.compositesb.2024.111717

具有亚微米粘弹性夹层和刚度和阻尼非常规组合的轻质硅和玻璃复合材料

The necessity of stiff structural materials with advanced damping characteristics has arisen naturally along with the technological evolution. However, despite ever-growing demand, the achievement of stiff materials with high damping factor remains challenging because of the antagonistic nature of the two properties. Here, this challenge is accomplished by exploiting the non-affine deformation of conventional laminated composites paired with the dissipative nature of the viscoelastic phase. Guided by a finite element design analysis, composites with flat submillimeter stiff layers and submicron viscoelastic interlayers are fabricated. The viscoelastic component consists of a prudently chemically architectured comb-like polydimethylsiloxane (PDMS) elastomer that properly adheres to the stiff silicon or glass layers, strong enough to withstand repeated dynamic cycles. The composites are fabricated using an unconventional but simple stacking route based on the diffusion of a platinum catalyst precursor into a reactive solvent-free PDMS melt. The fabricated composites, Si/PDMS and glass/PDMS, exhibit an elastic modulus higher than common monolithic glass, they are as light as glass but have about four orders of magnitude higher loss factor. The composites markedly outperform numerous customary materials, they escape the Ashby limit for mechanical damping – stiffness trade-off, and their exceptional combinations of properties are maintained over a broad range of temperatures and frequencies.

随着技术的发展，对具有先进阻尼特性的刚性结构材料的需求自然产生。然而，尽管需求不断增长，但由于两种特性的对抗性质，实现具有高阻尼系数的刚性材料仍然具有挑战性。在这里，这一挑战是通过利用传统层压复合材料的非仿射变形与粘弹性相的耗散特性相结合来完成的。在有限元设计分析的指导下，制备了具有亚毫米平面刚性层和亚微米粘弹性夹层的复合材料。粘弹性组件由一种精心设计的梳状聚二甲基硅氧烷(PDMS)弹性体组成，该弹性体可以适当地粘附在坚硬的硅或玻璃层上，足以承受反复的动态循环。复合材料的制备采用了一种非常规但简单的堆叠方法，该方法基于铂催化剂前驱体扩散到无溶剂反应性PDMS熔体中。所制备的硅/PDMS和玻璃/PDMS复合材料的弹性模量高于普通单片玻璃，它们与玻璃一样轻，但损耗因子高出约4个数量级。复合材料的性能明显优于许多传统材料，它们摆脱了机械阻尼-刚度权衡的Ashby极限，并且它们的特殊组合性能在广泛的温度和频率范围内保持不变。

Methacrylate-based shape manipulable wood with catalyst-free dynamic hemiacetal ester networks

Yi Tan, Youming Dong, Weidong Gu, Qiang Gao, Tao Liu, Hui Chen, Shanshan Gong, Kaili Wang, Sheldon Q. Shi, Jianzhang Li

doi:10.1016/j.compositesb.2024.111720

具有无催化剂动态半缩醛酯网络的基于甲基丙烯酸酯的形状可操纵木材

The insufficient structural design and unfriendly preparation have greatly limited the development of thermal-induced shape memory materials. A methyl methacrylate (MMA)-based shape manipulable wood composite (SMW) is fabricated by integrating the catalyst-free hemiacetal ester networks with hierarchical anisotropic wood skeleton based on free radical in-situ polymerization and cross-linking reaction. In the as-obtained SMW, hierarchical wood framework (WF) and high-strength MMA act as mechanical skeleton and polymer network backbone, respectively, while methacrylic acid (MAA) promotes dynamic cross-linkage. The SMW possesses satisfactory comprehensive performances including desirable preparation efficiency, ideal optical property, anisotropic light-guiding effect, low thermal conductivity (≈0.22 W m−1 K−1), satisfactory UV shielding effect and benign mechanical performances (longitudinal tensile strength of 34.54 MPa and flexural strength of 53.64 MPa). The catalyst-free dynamic exchange reaction combined with hierarchical wood skeleton endows the obtained SMW with shape memorability and manipulability, and the shape can be manipulated on demand without environmental-burden catalyst, which facilitates the industrial exploration, add-value development, and intelligent application of wood-based materials.

结构设计的不完善和制备的不友好极大地限制了热致形状记忆材料的发展。通过自由基原位聚合和交联反应，将无催化剂半缩醛酯网络与分层各向异性木材骨架相结合，制备了甲基丙烯酸甲酯基可塑木材复合材料(SMW)。在SMW中，分层木框架(WF)和高强度MMA分别作为机械骨架和聚合物网络骨干，而甲基丙烯酸(MAA)促进动态交联。SMW具有令人满意的综合性能，包括良好的制备效率、理想的光学性能、各向异性导光效果、低导热系数(≈0.22 W m−1 K−1)、良好的紫外线屏蔽效果和良好的力学性能(纵向拉伸强度为34.54 MPa，弯曲强度为53.64 MPa)。无催化剂动态交换反应与层次化木骨架相结合，使所获得的SMW具有形状可记忆性和可操作性，且形状可按需操纵，无需环境负担催化剂，有利于木质材料的产业化探索、增值开发和智能化应用。

Manufacturing ultra-high performance geopolymer concrete (UHPGC) with activated coal gangue for both binder and aggregate

Jun Zhao, Aiguo Wang, YingCan Zhu, Jian-Guo Dai, Qiong Xu, Kaiwei Liu, Fajun Hao, Daosheng Sun

doi:10.1016/j.compositesb.2024.111723

以活性煤矸石为粘结剂和骨料制备超高性能地聚合物混凝土

The use of coal gangue in the preparation of ultra-high performance concrete (UHPC) not only effectively solves the environmental problem, but also reduces the economic cost and carbon emission of UHPC manufacturing. In this study, calcined coal gangue aggregates and calcined coal gangue powder are used to prepare ultra-high performance geopolymer concrete (UHPGC). The result indicates that the higher concentration of Q3 (-101.1) [SiO4] structure and four- and five-coordinated Al, the higher the reactivity of calcined coal gangue. Active calcined coal gangue aggregate can compact the interface transition zone (ITZ) and reduce the porosity of UHPGC. The 28 d-compressive strength of UHPGC (C750F750) prepared from coal gangue aggregate calcined at 750 °C reaches 143.1 MPa. The width of the ITZ between aggregate and matrix of the C750F750 is 34 μm. Compared with traditional UHPC, UHPGC has a lower comprehensive cost and carbon emission. This study provides a low-carbon and low-cost UHPC, while also providing technical support for the resource utilization and high-value utilization of coal gangue.

利用煤矸石制备超高性能混凝土(UHPC)不仅有效地解决了环境问题，而且降低了UHPC制造的经济成本和碳排放。采用煅烧煤矸石骨料和煅烧煤矸石粉制备超高性能地聚合物混凝土(UHPGC)。结果表明:Q3 (-101.1) [SiO4]结构和四、五配位Al浓度越高，煅烧煤矸石的反应活性越高;活性煅烧煤矸石骨料可以压缩界面过渡区，降低UHPGC的孔隙率。煤矸石骨料750℃煅烧制得的UHPGC (C750F750) 28 d抗压强度达143.1 MPa。C750F750的集料与基体之间的界面宽度为34 μm。与传统UHPC相比，UHPGC具有较低的综合成本和碳排放。本研究提供了一种低碳、低成本的UHPC，同时也为煤矸石的资源化利用和高价值利用提供了技术支持。

Microfluidic Bubble-templating 3D Printing of Ordered Macroporous Hydrogels

Qimin Dai, Wenya Liao, Junfeng Liu, Mingyang Su, Pengfei Wang, Zhongbin Xu, Xing Huang

doi:10.1016/j.compositesb.2024.111725

有序大孔水凝胶的微流控气泡模板3D打印

Macroporous hydrogels have broad applications in tissue engineering, drug delivery and flexible biosensors, etc. However, it is still difficult to simultaneously control both the shape and the internal macroporosity. Here, we introduce a microfluidic bubble-templating 3D printing method based on thermosensitive composite hydrogel inks consisting of alginate and Pluronic F127. Two-phase laminar shear in coaxial microfluidics generates exceptionally monodispersed microbubbles as templates, while 3D printing technique provides spatial distribution of these microbubbles. Microbubble generation and 3D printing are coordinated and rheology of the inks are optimized to improve the systematic printability. Macroporous hydrogels with both monodispersed and gradient macropore structures are prepared and characterized. The internal anisotropic macroporosity distribution leads to inhomogeneous mechanical property in the products, making them competent as ergonomic artificial knuckle skins. The microfluidic-assisted 3D printing methodology provides a new insight for bottom-up design of porous soft materials.

大孔水凝胶在组织工程、药物输送和柔性生物传感器等方面有着广泛的应用。然而，同时控制形状和内部宏观孔隙率仍然很困难。本文介绍了一种基于海藻酸盐和Pluronic F127组成的热敏复合水凝胶油墨的微流控气泡模板3D打印方法。同轴微流体中的两相层流剪切产生异常单分散的微气泡作为模板，而3D打印技术提供了这些微气泡的空间分布。微泡生成与3D打印相协调，优化了油墨的流变性，提高了系统的可打印性。制备了具有单分散和梯度大孔结构的大孔水凝胶，并对其进行了表征。内部各向异性的大孔隙分布导致产品的力学性能不均匀，使其成为符合人体工程学的人造关节皮。微流体辅助3D打印方法为多孔软质材料的自底向上设计提供了新的视角。

New insights into the influencing mechanism of ultrasonic vibration on interface of Al/Mg bimetal composites by compound casting using simulation calculation and experimental verification

Qingqing Li, Wenming Jiang, Yuancai Xu, Linghui Yu, Xiaopeng Yu, Zitian Fan

doi:10.1016/j.compositesb.2024.111726

通过模拟计算和实验验证，对超声振动对复合铸造Al/Mg双金属复合材料界面的影响机理有了新的认识

In this work, the numerical simulation of acoustic pressure distribution in ultrasonic vibration-assisted compound casting of Al/Mg bimetal composites was conducted. Relevant experimental verification was also performed to understand the influence of ultrasonic vibration treatment (UVT) on the interfacial microstructures and mechanical properties of the Al/Mg bimetal composites. Results revealed that the acoustic pressure distributions in the AZ91D melt were related to the vibration frequencies. The effective cavitation area at the Al/Mg interface reached the maximum percentage of 95.6%, with the ultrasonic frequency of 20 kHz. The experimental results found that the Al/Mg interface without UVT was composed of Al–Mg intermetallic compounds (IMCs, i.e., Al3Mg2 and Al12Mg17) layer and eutectic layer. The oxide film and gas gap were existed between the two layers. The Mg2Si particles were gathered at the IMCs layer. The interfacial grains were coarse and their growth was directional. With UVT, the effective cavitation was occurred at the Al/Mg interface. The oxide film was broken, and the gas gap was eliminated. The interfacial microstructures were significantly refined. Due to the accelerated elemental diffusion and solute transfer by UVT, a more homogeneous Al/Mg interface was obtained. The Mg2Si particles were refined and formed at the eutectic layer. The microhardness mismatch of the IMCs layer and eutectic layer was decreased by UVT. The shear strength of the Al/Mg bimetal composites with UVT was enhanced to 62.2 MPa, which increased by 62.8%, compared with that without UVT.

本文对超声振动辅助铸造Al/Mg双金属复合材料过程中的声压分布进行了数值模拟。为了解超声振动处理(UVT)对Al/Mg双金属复合材料界面组织和力学性能的影响，进行了相关的实验验证。结果表明，AZ91D熔体内的声压分布与振动频率有关。当超声频率为20 kHz时，Al/Mg界面处的有效空化面积最大，达到95.6%。实验结果发现，无UVT的Al/Mg界面由Al - Mg金属间化合物(IMCs，即Al3Mg2和Al12Mg17)层和共晶层组成。两层之间存在氧化膜和气隙。Mg2Si颗粒聚集在IMCs层。界面晶粒粗大，生长有方向性。UVT在Al/Mg界面处产生了有效的空化。氧化膜破裂，消除气隙。界面微观结构明显细化。由于UVT加速了元素扩散和溶质转移，得到了更均匀的Al/Mg界面。Mg2Si颗粒在共晶层细化形成。UVT减小了IMCs层和共晶层的显微硬度失配。加入UVT后，Al/Mg双金属复合材料的抗剪强度达到62.2 MPa，比未加入UVT时提高了62.8%。

Highly transparent, self-cleaning, and UV-shielding composite coating: when eco-friendly waterborne omniphobic surface cooperates with quantum dots

Jianwen Peng, Peng Ye, Fei Xu, Xinyu Bu, Ruitao Wang, Dan Lin, Sicheng Yuan, Yanji Zhu, Huaiyuan Wang

doi:10.1016/j.compositesb.2024.111731

高透明、自洁、防紫外线复合涂层:生态友好型水性全疏表面与量子点协同

Solar energy is an inexhaustible carbon-free source, and solar cells are invaluable enablers for achieving carbon neutrality; however, the surface contamination on the glass of solar cells poses a formidable obstacle to maintaining a high power conversion efficiency. Existing self-cleaning coatings for combating surface contamination generally lack the highly comprehensive properties required for applications in real-world conditions. Herein, eco-friendly, highly transparent, waterborne omniphobic Si2.5WPA/AmZnO@SiO2 coatings were developed by the ingenious design of polydimethylsiloxane-grafted waterborne polyacrylate (SixWPA) and (3-aminopropyl)triethoxysilane-modified-SiO2 encapsulated ZnO quantum dots (AmZnO@SiO2). The enriched PDMS flexible chains on the coating surface overcame the energy barriers for moving liquids, and the AmZnO@SiO2 inside absorbed and scattered UV rays, which synergistically endowed the coating with self-cleaning and UV-shielding properties. Importantly, after the self-cleaning procedure, the light transmission of dust-contaminated glass and short-circuit current density of corresponding solar cells could be restored to 99.78% and 97.77% of initial metrics, respectively. Furthermore, the commonly ignored self-cleaning mechanism was investigated and proposed: the coating weakened the adhesion of dust particles and utilized the drag force generated during liquid slip to achieve self-cleaning. The coating also showed good UV/humidity/thermal stability and mechanical strength, providing a design blueprint for outdoor optical device protection.

太阳能是取之不尽、用之不竭的无碳能源，太阳能电池是实现碳中和的无价推动者;然而，太阳能电池玻璃表面的污染对保持高功率转换效率构成了巨大的障碍。现有的用于对抗表面污染的自清洁涂层通常缺乏在实际条件下应用所需的高度综合性能。通过巧妙地设计聚二甲基硅氧烷接枝水性聚丙烯酸酯(SixWPA)和(3-氨基丙基)三乙氧基硅烷修饰的sio2包封ZnO量子点(AmZnO@SiO2)，开发了环保、高透明、水性全疏水性Si2.5WPA/AmZnO@SiO2涂料。涂层表面丰富的PDMS柔性链克服了液体移动的能量障碍，内部的AmZnO@SiO2吸收和散射紫外线，协同赋予涂层自清洁和紫外线屏蔽性能。重要的是，经过自清洁程序后，粉尘污染玻璃的透光率和相应太阳能电池的短路电流密度可以分别恢复到初始指标的99.78%和97.77%。此外，研究并提出了通常被忽视的自清洁机理:涂层削弱了粉尘颗粒的粘附力，并利用液体滑动时产生的阻力来实现自清洁。该涂层还表现出良好的紫外线/湿度/热稳定性和机械强度，为户外光学器件保护提供了设计蓝图。

Composites Science and Technology

Regulating integral alignment of magnetic MXene nanosheets in layered composites to achieve high-effective electromagnetic wave absorption

Yang Zhou, Jiahao Sun, Zhaoyang Li, Bing Zhou, Chuntai Liu, Yuezhan Feng

doi:10.1016/j.compscitech.2024.110746

调节磁性MXene纳米片在层状复合材料中的整体排列，实现高效的电磁波吸收

The integral structure design is equally crucial to the regulation of electromagnetic components in microwave absorbing materials. In this work, magnetic MXene/polyvinylidene fluoride composites with integral nacre-like structure were prepared by successive hot-pressing process to realize the layered arrangement of Ni anchored MXene (Ni@MXene). The order degree of Ni@MXene from random to orientation can be adjusted by gradually changing compression ratio. Interestingly, increasing the orientation degree of Ni@MXene effectively improves the dielectric constant, minimal reflection loss (RLmin) and effective absorption bandwidth (EAB) of the layered composites. This is attributed to the improved loss ability by increasing the contact areas between Ni@MXene and vertically incident electromagnetic waves, inducing multiple scattering/reflection effect, and the formation of localized conductive pathways. As a result, the layered composite with optimal layered structure delivers the best electromagnetic microwave absorption performance with a RLmin of −69.8 dB and an EAB of 4.77 GHz. Besides, increasing the orientation degree can also optimize the mechanical properties of the layered composites, with the maximum tensile strength and toughness of 32.6 MPa and 115.0 MJ m−3, respectively. Therefore, this work proves the adjustability of absorption performance by changing the distribution of absorbents, and integrates the structure and function for microwave absorption materials.

整体结构设计对于微波吸收材料中电磁成分的调节同样至关重要。本研究采用连续热压工艺制备了具有整体珍珠状结构的磁性 MXene/ 聚偏二氟乙烯复合材料，实现了镍锚定 MXene（Ni@MXene）的分层排列。通过逐渐改变压缩比，可以调整 Ni@MXene 的有序度，从无序到取向。有趣的是，增加 Ni@MXene 的取向度可有效改善层状复合材料的介电常数、最小反射损耗（RLmin）和有效吸收带宽（EAB）。这是由于增加了 Ni@MXene 与垂直入射电磁波的接触面积，产生了多重散射/反射效应，并形成了局部导电通路，从而提高了损耗能力。因此，具有最佳分层结构的分层复合材料具有最佳的电磁微波吸收性能，RLmin 为 -69.8 dB，EAB 为 4.77 GHz。此外，增加取向度还能优化层状复合材料的机械性能，其最大拉伸强度和韧性分别为 32.6 MPa 和 115.0 MJ m-3。因此，这项工作证明了通过改变吸收剂的分布可调节吸收性能，并将微波吸收材料的结构与功能融为一体。

Reconstruction and Prediction of Mode-I Cohesive Law using Artificial Neural Network

Chongcong TAO, Chao ZHANG, Hongli JI, Jinhao QIU

doi:10.1016/j.compscitech.2024.110755

基于人工神经网络的i型内聚规律重构与预测

Cohesive zone model (CZM) is a widely used tool for simulating both static and fatigue damage propagation for bonded area in composite materials. Under static loading, the damage propagation behavior is governed by a cohesive law (CL), the shape of which is an important property especially when non-linear damage mechanisms such as fiber bridging is involved. In this work, a CZM driven by artificially neural network (ANN) for simulating mode-I damage propagation is proposed, where the traction-separation relationship is calculated by a multi-layer perceptron (MLP). More importantly, a reconstruction method is proposed to extract the CL through the training of the neural network using a simple load-displacement (P-U) relation of a double cantilever beam (DCB) as the only inputs, without the need to measure the crack opening displacement (COD). The proposed method is first validated using finite element generated virtual experimental data with various CL shapes before being applied to experimental data, where good correlations are obtained, proving the effectiveness of the proposed method.

黏结区模型(CZM)是一种广泛应用于模拟复合材料黏结区的静态和疲劳损伤扩展的工具。在静载荷作用下，损伤传播行为受粘聚规律(CL)的支配，粘聚规律的形状是一个重要的特性，特别是当涉及到非线性损伤机制(如光纤桥接)时。本文提出了一种由人工神经网络驱动的用于模拟i型损伤传播的CZM，其中牵引-分离关系由多层感知器(MLP)计算。更重要的是，提出了一种不需要测量裂纹张开位移(COD)，以双悬臂梁(DCB)的简单荷载-位移(P-U)关系作为唯一输入，通过神经网络训练提取裂纹张开位移的重构方法。首先利用有限元生成的具有各种CL形状的虚拟实验数据对所提方法进行验证，然后将其应用于实验数据，获得了良好的相关性，证明了所提方法的有效性。

Explainable Artificial Intelligence Prediction of Defect Characterization in Composite Materials

Vahid Daghigh, Somayeh Bakhtiari Ramezani, Hamid Daghigh, Thomas E. Lacy

doi:10.1016/j.compscitech.2024.110759

复合材料缺陷表征的可解释人工智能预测

Non-destructive evaluation (NDE) techniques are integral across diverse applications for void detection within composites. Infrared (IR) thermography (IRT) is a prevalent NDE technique that utilizes reverse heat transfer principles to infer defect characteristics by analyzing temperature distribution. Although the forward heat transfer problem is well-posed, its inverse counterpart lacks uniqueness, posing non-unique solutions. The present study performs simulations using finite element analysis (FEA) in defective (a penny-shaped defect) composites through which the heat transfer flux is modeled. A total of 2100 simulations with various defect positions and sizes (depth, size, and thickness) are executed, and the corresponding surface temperature vs. time and vs. distance diagrams are extracted. The FEA outputs provide ample input data for developing an explainable artificial intelligence (XAI) model to estimate the defect characteristics. A detailed feature engineering task is performed to select the representative information from the diagrams. Explainable decision tree-based machine learning (ML) models with transparent decision paths based on derived features are developed to predict the defect depth, size, and thickness. The ML models’ results suggest superb accuracy (R2 = 0.92 to 0.99) across all three defect characteristics. The provided workflow sets a benchmark applicable to a range of fields, including health monitoring.

非破坏性评估 (NDE) 技术在复合材料空隙检测的各种应用中不可或缺。红外（IR）热成像（IRT）是一种普遍的无损检测技术，它利用反向传热原理，通过分析温度分布来推断缺陷特征。虽然正向传热问题的假设条件良好，但其反向对应问题却缺乏唯一性，提出了非唯一解。本研究使用有限元分析（FEA）对缺陷（一分钱形状的缺陷）复合材料进行模拟，并通过该模型对热传导通量进行建模。共执行了 2100 次具有不同缺陷位置和尺寸（深度、尺寸和厚度）的模拟，并提取了相应的表面温度与时间和距离的关系图。有限元分析的输出结果为开发可解释人工智能 (XAI) 模型提供了充足的输入数据，用于估算缺陷特征。为了从图表中选择具有代表性的信息，需要执行一项详细的特征工程任务。基于可解释决策树的机器学习 (ML) 模型具有基于衍生特征的透明决策路径，可用于预测缺陷深度、尺寸和厚度。ML 模型的结果表明，在所有三个缺陷特征方面都具有极高的准确性（R2 = 0.92 至 0.99）。所提供的工作流程为包括健康监测在内的一系列领域设定了基准。

The Thermal Conductivity of Graphite Composite Insulation Boards: A Theoretical and Experimental study

Tengfei Zhao, Xianquan Wang, Genbao Liu, Jianlin Zhu, Shiping Yin

doi:10.1016/j.compscitech.2024.110760

石墨复合保温板导热性能的理论与实验研究

Graphite composite insulation boards (GCIB) have emerged as a promising solution in the construction industry, offering a combination of fire resistance, high temperature stability, and excellent insulation properties. As their usage continues to increase, it is crucial to develop and validate a more accurate theoretical model for the effective design and optimization of building insulation systems. Traditional models including series and parallel models are employed for estimating the thermal conductivity of GCIB but revealed higher relative errors and lower theoretical calculation accuracy. Therefore, the primary objective is to design and validate a more efficient theoretical model for thermal conductivity prediction in GCIB. This paper investigates the thermal conductivity of GCIB under varying composition ratios by designing a novel Parallel-Series Parallel (PSP) approach. The PSP model is designed based on a single basic cell where the graphite polystyrene particles are employed as the matrix material while cement, vitrified microspheres, and silica fume are used as inclusion materials. Then, the thermal conductivity unit is divided into three parallel heat conduction subunits where the matrix materials and inclusion materials in the three subunits are integrated in a series-parallel manner to provide a more realistic representation of the heat transfer mechanisms within the composite. For a comprehensive assessment, the study encompasses theoretical analysis, empirical assessment, and finite element (FE) simulations to illustrate its thermal properties. The predicted thermal conductivity reveals perfect consensus in comparison with the FE and experimental test outcomes by achieving lower relative errors of 2.7%∼3.8% and 1.9%∼ 3.0% respectively. The model validated through numerical simulations and sample experiments illustrates a significant improvement in accuracy of about 76.4%∼94.3% when compared to traditional series and parallel methods. Prominently, the findings indicate that the thermal conductivity of GCIBs declines considerably as the volumetric ratio of graphite polystyrene particles (Ф1 / Ф3) increases and stabilizes when the proportion reaches 10, emphasizing the importance of optimizing material composition to enhance the thermal performance of GCIB. Overall, the validated PSP model by accurately determining the thermal conductivity of GCIB serves as a reliable tool for designing and optimizing high-performance insulation materials, contributing to energy efficiency and sustainability in building and construction industries.

石墨复合保温板(GCIB)在建筑行业已经成为一种很有前途的解决方案，它具有耐火、高温稳定性和优异的保温性能。随着它们的使用不断增加，开发和验证一个更准确的理论模型对于有效设计和优化建筑保温系统至关重要。传统的串联和并联模型用于估算GCIB的导热系数，但相对误差较大，理论计算精度较低。因此，主要目标是设计和验证一个更有效的理论模型来预测GCIB的导热系数。本文通过设计一种新颖的并联-串联并联(PSP)方法，研究了不同组成比下GCIB的导热系数。PSP模型是基于单个基本电池设计的，其中石墨聚苯乙烯颗粒被用作基体材料，而水泥、玻璃化微球和硅灰被用作包合材料。然后，将导热单元划分为三个平行的导热亚单元，其中三个亚单元中的基体材料和包合材料以串并联的方式集成，以更真实地表示复合材料内部的传热机制。为了进行全面的评估，该研究包括理论分析，经验评估和有限元(FE)模拟来说明其热性能。预测的热导率与有限元和实验测试结果的相对误差较低，分别为2.7% ~ 3.8%和1.9% ~ 3.0%。通过数值模拟和样本实验验证，该模型与传统的串联和并行方法相比，精度显著提高，约为76.4% ~ 94.3%。研究结果表明，随着石墨聚苯乙烯颗粒体积比(Ф1 / Ф3)的增加，GCIB的导热系数显著下降，并在体积比达到10时趋于稳定，强调了优化材料组成以提高GCIB导热性能的重要性。总的来说，通过准确确定GCIB的导热系数，验证的PSP模型可以作为设计和优化高性能保温材料的可靠工具，有助于提高建筑和建筑行业的能源效率和可持续性。

来源：复合材料力学仿真Composites FEM

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