【新文速递】2023年10月29日复合材料SCI期刊最新文章

今日更新：Composite Structures 11 篇，Composites Part A: Applied Science and Manufacturing 1 篇，Composites Science and Technology 2 篇Composite StructuresBistable hybrid symmetric laminates with a clamped-clamped boundary condition: an experimental and numerical investigationZhang Zhimin, Lou Chungang, Liang Yong, Pan Diankundoi:10.1016/j.compstruct.2023.117654具有夹紧-夹紧边界条件的双稳态混合对称层压板：实验和数值研究In this work, a clamped-clamped boundary condition is considered for a family of bistable hybrid symmetric laminates in which the direction of curvature does not change during the snap-through process between the two stable configurations. The laminates were modeled using finite element analysis to predict the characteristics of stable configurations, including the distributions of curvatures and out-of-plane displacement in two directions, and then the results were validated by experiments. The snap-through behaviors of the bistable laminates under the clamped-clamped boundary condition were investigated numerically and experimentally and then compared with the preloaded laminates with the same boundary condition. The results showed that the bistable laminates require a lower snap-through load than the preloaded laminates when they have a similar maximum out-of-plane displacement. The loading position, lay-up design, and length of the clamped region were employed as variables to discover the features of snap-through behavior. It was found that the unsymmetric deformation mode was present regardless of the load position during the snap-through behavior of these bistable laminates. At last, a variable cross-section tube consisting of two bistable laminates was proposed, and the area of the cross-section could be increased by 80% after the snap-through of the two bistable laminates.在这项研究中，考虑了双稳态混合对称层压板系列的夹紧-夹紧边界条件，其中曲率方向在两个稳定构型之间的快穿过程中不会改变。利用有限元分析对层压板进行建模，预测稳定构型的特征，包括两个方向的曲率和平面外位移分布，然后通过实验对结果进行验证。通过数值和实验研究了双稳态层压板在夹紧-夹紧边界条件下的扣穿行为，并与具有相同边界条件的预加载层压板进行了比较。结果表明，当双稳态层压板具有相似的最大平面外位移时，其所需的快穿载荷低于预加载层压板。加载位置、层叠设计和夹紧区域的长度被用作变量，以发现快穿行为的特征。研究发现，在这些双稳态层压板的快穿行为中，无论加载位置如何，都存在非对称变形模式。最后，提出了一种由两块双稳态层压板组成的可变截面管，两块双稳态层压板快穿后，截面面积可增加 80%。Multi Objective Optimization Methods for Damage Assessment of Composite Laminates: A ReviewDress Genetu A., Koricho Ermias G., Regassa Y., Woldemichael D.E., Woldeyohannes A.D.doi:10.1016/j.compstruct.2023.117655复合材料层压板损伤评估的多目标优化方法：综述The goal of this paper is to present a review of multi-objective optimization (MOO) techniques used in the damage assessment of composite laminates, with regard to damage identification, damage detection, damage quantification, and damage prediction models or approaches. Prior recognition of damage is crucial to ensure the performance and integrity of a structure of high structural responsibility. It is only then catastrophic structural failure or massive property loss and even in human casualties, in extreme situations, can be avoided or at least reduced. As such damage assessment is required, especially using advanced optimization and multi-objective optimization techniques, to prevent the failure of structural laminated composites. According to researchers, AI-based optimization algorithms are preferable to programmed inspections, conventional methods (like ultrasonic and magnetic damage or acoustic damage assessment methods), model or non-model (feature-based methods), and both in the sense that they are quick, universal, and less expensive methods for damage assessment. Unfortunately, there have only been a few or a small number of research investigations, particularly for damage prediction.本文旨在综述复合材料层压板损伤评估中使用的多目标优化（MOO）技术，包括损伤识别、损伤检测、损伤量化以及损伤预测模型或方法。事先识别损伤对于确保结构责任重大的结构的性能和完整性至关重要。只有这样，在极端情况下才能避免或至少减少灾难性的结构失效或巨大的财产损失，甚至是人员伤亡。因此，需要进行损伤评估，特别是采用先进的优化和多目标优化技术，以防止结构层压复合材料失效。研究人员认为，基于人工智能的优化算法优于程序化检查、传统方法（如超声波和磁损伤或声学损伤评估方法）、模型或非模型（基于特征的方法），而且两者都是快速、通用和成本较低的损伤评估方法。遗憾的是，目前只有少数研究调查，特别是在损伤预测方面。Buckling optimization of variable-stiffness composite plates via variable stiffness optimization algorithmJing Zhao, Duan Lei, Wang Siqi, Li Biaodoi:10.1016/j.compstruct.2023.117657通过变刚度优化算法对变刚度复合板进行屈曲优化A variable stiffness optimization (VSO) algorithm is presented for optimizing variable-stiffness composite (VSC) plates with linear fiber path functions. A new definition of lamination parameters characterizing the distances between stacking configurations of VSC plates is presented. Using the inherent sensitivity of bending stiffness of composite laminates, the concept of “through thickness design” is introduced. The first step is to determine a good initial point for the VSC plates using three-dimensional sampling optimization (3DSO). The fiber angle design variables are then categorized into three groups. By optimizing the three groups' design variables sequentially and iteratively, the stiffness of the VSC plates is stiffened part by part until an optimum is reached. Lastly, the obtained optimum is redesigned accounting for the curvature constraint. The finite element method (FEM) is developed for the buckling analysis of VSC plates, and both Q4 and Q8 elements are employed to verify the accuracy and convergence of the FEM. Under a variety of boundary conditions and loading cases, FEM and VSO algorithm are used to maximize the buckling load of square and rectangular symmetrical VSC plates. Optimal results are compared with those available in the literature, demonstrating the effectiveness, robustness, and efficiency of the VSO algorithm.本文提出了一种可变刚度优化（VSO）算法，用于优化具有线性纤维路径函数的可变刚度复合材料（VSC）板。本文提出了表征 VSC 板堆叠配置之间距离的层压参数的新定义。利用复合材料层压板弯曲刚度的固有敏感性，引入了 "通厚设计 "的概念。第一步是利用三维取样优化（3DSO）为 VSC 板确定一个良好的初始点。然后将纤维角度设计变量分为三组。通过依次迭代优化三组设计变量，逐部分提高 VSC 板的刚度，直至达到最优。最后，根据曲率约束条件对获得的最佳值进行重新设计。为 VSC 板的屈曲分析开发了有限元法（FEM），并采用 Q4 和 Q8 元素来验证有限元法的准确性和收敛性。在各种边界条件和加载情况下，使用有限元法和 VSO 算法使正方形和矩形对称 VSC 板的屈曲载荷最大化。最佳结果与文献中的结果进行了比较，证明了 VSO 算法的有效性、稳健性和高效性。Out-of-plane moving load response and vibrational behavior of sandwich curved beams with GPLRC face sheets and porous coreSafaei M., Malekzadeh P., Golbahar Haghighi M.R.doi:10.1016/j.compstruct.2023.117658采用 GPLRC 面板和多孔芯材的夹层曲面梁的平面外移动载荷响应和振动行为As a first endeavor, the out-of-plane free vibrational behaviors and moving load responses of sandwich curved beams with graphene platelets reinforced composite face sheets and porous core (GPLRC-FS-PC) are carried out. The governing equations are derived based on the first-order shear deformation theory (FSDT) using Hamilton’s principle, which are discretized by employing the differential quadrature method (DQM) and Newmark’s method in the spatial and time domains, respectively. To simulate the moving load using the DQM, the Heaviside function approach is utilized. The effective elastic properties of face sheets are estimated using Halpin-Tsai micromechanical model. The approach is validated by presenting convergence studies and accuracy verification followed by parametric studies. The numerical results indicate that by adding little amount of graphene platelets (GPLs) into the face sheets and core layer, the fundamental natural frequency and the displacement amplitudes under moving load significantly increases and decreases, respectively, regardless of the beam boundary conditions. It is revealed that the GPLs distribution patterns in face sheets and the core porosity distribution patterns affect the critical load velocities of the GPLRC-FS-PC sandwich curved beams. Also, it is shown that the frequency parameters strongly depend on the face sheet to core thickness ratio.作为首次尝试，研究了石墨烯平板增强复合材料面片和多孔芯材（GPLRC-FS-PC）夹层曲面梁的平面外自由振动行为和移动载荷响应。利用汉密尔顿原理，基于一阶剪切变形理论（FSDT）推导出控制方程，并在空间域和时间域分别采用微分正交法（DQM）和纽马克法将其离散化。使用 DQM 模拟移动载荷时，采用了 Heaviside 函数方法。面片的有效弹性特性是利用 Halpin-Tsai 微机械模型估算的。通过收敛性研究和精度验证以及参数研究，对该方法进行了验证。数值结果表明，在面片和芯层中添加少量石墨烯微粒（GPLs）后，无论梁的边界条件如何，移动载荷作用下的基固有频率和位移振幅分别显著增加和减小。研究表明，GPLs 在面层中的分布模式和芯层孔隙率分布模式会影响 GPLRC-FS-PC 夹层曲面梁的临界载荷速度。此外，研究还表明频率参数与面片与夹芯厚度比密切相关。Stability analysis of pultruded basalt fiber-reinforced polymer (BFRP) tube under axial compressionChen Yu, Zhang Chuntaodoi:10.1016/j.compstruct.2023.117660拉挤玄武岩纤维增强聚合物（BFRP）管在轴向压缩下的稳定性分析This study analyzed mechanical properties and stability of pultruded basalt fiber-reinforced polymer (BFRP) tubes under compressive axial loading for large-span space and truss structures applications. This study assessed the compressive strength of BFRP tubes with three different cross-sectional shapes and investigated the failure modes under compression with slenderness ratios ranging from 20 to 150. The results demonstrated that short BFRP tubes can achieve a compressive strength of up to 122.36 MPa with a compressive elastic modulus of 40.39 GPa. Three types of compressive failure modes were observed in the BFRP tubes, including local material, critical, and overall buckling failures. Furthermore, based on the analysis of experiment results, two design-oriented three-stage theoretical models were proposed for BFRP tubes with three different cross-sectional shapes. The proposed models were able to predict both the stress-strain and load-lateral deflection curves by taking into account the post-peak softening behavior of the stress–strain curve. In addition, a stability equation was also derived for predicting the compressive strength of slender BFRP tubes and was validated by experiments. The predictions derived from proposed models were consistent with experiment results.本研究分析了用于大跨度空间和桁架结构的拉挤玄武岩纤维增强聚合物（BFRP）管材在压缩轴向载荷作用下的力学性能和稳定性。该研究评估了三种不同截面形状的 BFRP 管材的抗压强度，并研究了细长比在 20 到 150 之间的压缩失效模式。结果表明，BFRP 短管的抗压强度可达 122.36 兆帕，抗压弹性模量为 40.39 GPa。在 BFRP 管中观察到三种抗压失效模式，包括局部材料失效、临界失效和整体屈曲失效。此外，根据对实验结果的分析，针对三种不同截面形状的 BFRP 管提出了两个以设计为导向的三阶段理论模型。考虑到应力-应变曲线的峰值后软化行为，所提出的模型能够预测应力-应变曲线和荷载-侧向挠度曲线。此外，还推导出了用于预测细长 BFRP 管抗压强度的稳定方程，并通过实验进行了验证。所建模型的预测结果与实验结果一致。Vibration characteristic analysis of three-dimensional sandwich cylindrical shell based on the Spectro-Geometric methodMeng Shuo, Zhong Rui, Wang Qingshan, Shi Xianjie, Qin Bindoi:10.1016/j.compstruct.2023.117661基于光谱几何法的三维夹层圆柱壳振动特性分析This paper presents the numerical investigations on the free and random vibration properties of thick cylindrical shells under the three-dimensional (3-D) elasticity theory. The analysis of these properties is conducted using the Rayleigh-Ritz method in conjunction with the Spectro-Geometric method (SGM). The cylindrical shell considered in this study is composed of fiber-reinforced composite and functionally graded porous graphene platelet reinforced composites (FGP-GPLRC). To simulate different boundary conditions, an artificial spring technique is utilized. The displacement components, as determined by SGM, are incorporated into the energy expression of the cylindrical shell. By applying the Rayleigh-Ritz method, the intrinsic frequencies and vibration modes of the cylindrical shell are obtained. Additionally, the power spectral density (PSD) function of the cylindrical shell under random excitation is obtained by the Pseudo-Excitation method (PEM). The accuracy and effectiveness of the present method are verified through comparative studies with existing literature and finite element method (FEM). Furthermore, an investigation on the effects of various parameters on the intrinsic frequency and random response of the cylindrical shell is conducted.本文介绍了在三维（3-D）弹性理论下对厚圆柱形壳体的自由和随机振动特性进行的数值研究。对这些特性的分析采用了雷利-里兹法（Rayleigh-Ritz method）和谱几何法（Spectro-Geometric method，SGM）。本研究考虑的圆柱形壳体由纤维增强复合材料和功能分级多孔石墨烯平板增强复合材料（FGP-GPLRC）组成。为了模拟不同的边界条件，采用了人工弹簧技术。由 SGM 确定的位移分量被纳入圆柱形外壳的能量表达式中。通过应用 Rayleigh-Ritz 方法，可以得到圆柱形外壳的固有频率和振动模式。此外，还通过伪激励法（PEM）获得了圆柱形外壳在随机激励下的功率谱密度（PSD）函数。通过与现有文献和有限元法（FEM）的对比研究，验证了本方法的准确性和有效性。此外，还研究了各种参数对圆柱形壳体固有频率和随机响应的影响。Quasi-static compression tests of overwrapped composite pressure vessels under low velocity impactI Mohammed Auwalu, Raghupathy Kaarthikeyan, De Victoria Garcia Baltazar Osvaldo, Onokpasah Lawson, Carvalho Roger, Mogensen Anders, Hassani Farzaneh, Njuguna Jamesdoi:10.1016/j.compstruct.2023.117662低速冲击下包覆复合材料压力容器的准静态压缩试验Pressure Vessels are being utilised in different applications that are indispensable including automobile, aerospace, underwater vehicles, oil and gas, chemical engineering among other applications. However, there is lack of knowledge on the influence of induced damage and the resulting performance of such vessels under quasi-static loading and axial compression. Specifically, the vessels studied in this study is made up of a high-density polyethylene liner and glass fibre overwraps. Therefore, this research investigated the load bearing capacities and the energy absorbed of the indented vessels in axial and hoop directions to determine the resistance of the vessels after such damaged using experiment, and damage characterisation microscopy, non-destructive testing and analysis. Quasi-static transverse and axial compression testing was performed on composite cylinders made of polyethylene liner and glass fibre overwraps. Both quasi-static and axial compression tests were performed with the Instron Machine 3382, quasi-static compression was performed at speed of 500 mm/min, while the axial compression test was performed at speed of 2.5 mm/min. The results for the damage profile and the effect on compressive strength of the composite damaged and two non-damaged cylinders was found to be relatively similar. Additionally, the results demonstrate that the quasi-static compression have little or no influence on the axial strength of the cylinders. The microscopic and Dolphicam2 results for damage characterisation on the cylinders revealed fibre break and delamination. On the other hand, visual examination results show local bucking and brooming failure at the bottom of the cylinders.压力容器被广泛应用于汽车、航空航天、水下航行器、石油和天然气、化学工程等各种不可或缺的领域。然而，人们对此类容器在准静态加载和轴向压缩条件下的诱导损伤影响及由此产生的性能缺乏了解。具体而言，本研究中的容器由高密度聚乙烯内衬和玻璃纤维外包装组成。因此，本研究通过实验、损伤表征显微镜、无损检测和分析，研究了压痕容器在轴向和环向的承载能力和吸收的能量，以确定容器受损后的阻力。对由聚乙烯内衬和玻璃纤维外包装制成的复合材料圆筒进行了准静态横向和轴向压缩试验。准静态和轴向压缩试验均使用 Instron 3382 机器进行，准静态压缩试验以 500 毫米/分钟的速度进行，而轴向压缩试验则以 2.5 毫米/分钟的速度进行。结果发现，受损的复合材料圆柱体和两个未受损的圆柱体的受损情况以及对抗压强度的影响相对相似。此外，结果表明准静态压缩对圆柱体的轴向强度几乎没有影响。显微镜和 Dolphicam2 检测结果表明，圆柱体的损伤特征包括纤维断裂和分层。另一方面，目视检查结果显示，圆柱体底部出现了局部弯曲和扫帚状破坏。The effect of recycled date palm tree fibers on the impact fatigue and residual static strength of adhesively bonded jointsMiri M., Ayatollahi M.R., Akhavan-Safar A., da Silva L.F.M.doi:10.1016/j.compstruct.2023.117664再生枣椰树纤维对粘合剂粘接接头冲击疲劳和残余静态强度的影响The role of natural fibers on the impact fatigue strength of bonded single lap joints (SLJs) has been experimentally investigated. The use of natural fiber offers several advantages, including the potential to recycle natural resources and the utilization of sustainable materials. Four types of natural date palm tree fibers (DPTFs) including Rachis, Petiole, Bunch, and Mesh were used to improve the impact fatigue life and the residual static strength of joints after enduring repetitive low energy impacts. The fibers were treated by 6 wt% of NaOH solution and cut manually to short size (0.5-2mm) and were used by weight ratios of 2 and 5%. The results show that the addition of DPTFs to the adhesive layer significantly improves the impact fatigue strength of the reinforced joints compared to neat adhesive SLJs. The joints reinforced by 5 wt% and 2 wt% of Mesh improved the impact fatigue life of the joints by 197% and 87%, respectively. The impact fatigue life of the joints modified by 5 wt% of fibers was more than the joints reinforced by 2 wt%. Fractography analysis also showed that DPTFs make the crack propagation more stable and increase the strength of the tested joints on different conditions.实验研究了天然纤维对粘接单搭接接头（SLJ）冲击疲劳强度的作用。天然纤维的使用具有多种优势，包括回收自然资源和利用可持续材料的潜力。实验中使用了四种天然枣椰树纤维（DPTFs），包括树轴、叶柄、树枝和网状纤维，以提高接头在经受重复低能量冲击后的冲击疲劳寿命和残余静态强度。这些纤维经 6 wt% 的 NaOH 溶液处理，手工切割成短尺寸（0.5-2 毫米），并按 2% 和 5% 的重量比使用。结果表明，与纯粘合剂 SLJs 相比，在粘合剂层中添加 DPTF 可显著提高增强接头的冲击疲劳强度。用 5 wt% 和 2 wt% 的网格布加固的接头的冲击疲劳寿命分别提高了 197% 和 87%。5 wt%纤维改性接头的冲击疲劳寿命高于 2 wt%纤维改性接头。碎裂分析还表明，DPTF 使裂纹扩展更加稳定，并提高了测试接头在不同条件下的强度。Lightweight airborne TPMS-filled reflective mirror design for low thermal deformationZeng Chaoqun, Wang Wei, Hai Kuo, Ma Shaoxingdoi:10.1016/j.compstruct.2023.117665 轻质机载 TPMS 填充反射镜设计，热变形小In recent decades, unmanned aerial vehicle airborne optical systems have gained a booming development. With the continuous pursuit of optical system performance, the thermal deformation of the reflector during temperature change constrains the further improvement of the system performance. Traditional open-back mirrors have difficulty meeting high-performance targets under temperature change. With the rapid development of 3D printing technology, the complex structures represented by TPMS have significantly increased the freedom of optical reflector design. This paper proposes a TPMS structure optimization design approach based on the homogenization performance model, which can accurately describe the TPMS structure performance and obtain structures with outstanding performance with minimal computing cost. A TPMS-filled reflector with a diameter of 400 mm and a height of 60 mm was designed with a mass reduction of about 70%. Results show that the final shape deviation of the mirror is below 20 nm RMS at room temperature and below 30 nm RMS at 50 ℃. Compared to open-back mirrors, TPMS-filled mirrors perform significantly better at high temperatures. This method helps with the application of TPMS in the design of opto-mechanical structures.近几十年来，无人机机载光学系统得到了蓬勃发展。随着对光学系统性能的不断追求，温度变化时反射镜的热变形制约了系统性能的进一步提高。传统的开背式反射镜在温度变化时难以达到高性能目标。随着 3D 打印技术的快速发展，以 TPMS 为代表的复杂结构大大提高了光学反射镜设计的自由度。本文提出了一种基于均质化性能模型的 TPMS 结构优化设计方法，可以准确描述 TPMS 结构性能，并以最小的计算成本获得性能优异的结构。设计了一个直径为 400 毫米、高度为 60 毫米的 TPMS 填充反射器，质量减轻了约 70%。结果表明，反射镜的最终形状偏差在室温下低于 20 nm RMS，在 50 ℃ 时低于 30 nm RMS。与开背式反射镜相比，TPMS 填充反射镜在高温下的性能明显更好。这种方法有助于在光机电结构设计中应用 TPMS。NONLINEAR VIBRATION STUDY OF A ROTOR BLADE BASED ON A NOVEL NON-POLYNOMIAL FUNCTIONRout Mrutyunjay, Sekhar Hota Sasankdoi:10.1016/j.compstruct.2023.117667基于新型非多项式函数的转子叶片非线性振动研究This work investigates the nonlinear free vibration of a turbomachinery blade, which is idealized as a rotating, conical, twisted shell of varying thickness reinforced with graphene platelets. Using the von Karman type of nonlinearity, the dynamic equilibrium equation for the twisted panel is obtained and solved by finite element method. The impact of the centrifugal force caused by rotation is taken into account, but the effect of the Coriolis force is neglected. The functionally graded twisted tapering conical shell has two alternative ways in which graphene platelets (GPLs) are reinforced in the thickness direction. The rule of mixture and the modified Halpin-Tsai model are used to compute the effective material properties of the twisted shell. The strain displacement relation is based on a new non-polynomial shear deformation theory. The parametric analysis performed at the endshows that nonlinear frequency increases when twist angle, rotational speed, tapper ratio, and weight fraction of GPLs increase. It is also observed that mode shapes are severely impacted by twist angle and rotational speed.本研究对涡轮机械叶片的非线性自由振动进行了研究，该叶片被理想化为一个旋转的、锥形的、用石墨烯平板增强的不同厚度的扭曲壳体。利用 von Karman 非线性类型，得到了扭曲面板的动态平衡方程，并通过有限元法进行了求解。其中考虑了旋转产生的离心力的影响，但忽略了科里奥利力的影响。功能分级扭曲锥形壳体有两种在厚度方向上增强石墨烯平板（GPL）的替代方法。混合规则和改进的 Halpin-Tsai 模型用于计算扭曲外壳的有效材料特性。应变位移关系基于新的非多项式剪切变形理论。在端部进行的参数分析表明，当扭转角、旋转速度、锥齿轮比和 GPL 重量分数增加时，非线性频率也会增加。此外，还观察到模态形状受到扭转角和旋转速度的严重影响。Numerical simulations and experiments of the deployment of a thin-walled bistable composite boomTortorici Daniele, Sabatini Marco, Laurenzi Susannadoi:10.1016/j.compstruct.2023.117669薄壁双稳态复合吊杆部署的数值模拟和实验For advanced space missions, meeting the concurrent requirements of increasing payload size while minimizing spacecraft volume can be achieved through the utilization of deployable structures. In a previous study, we conducted a characterization of a thin/walled boom in terms of its interaction between attitude and elastic dynamics when fully deployed. In this current work, we have developed a numerical model to analyze the critical phase of the deployment process. We compared the model's predictions with theoretical expectations and experimental data, and found a strong agreement between them. Additionally, we investigated the effects of bistability on the deployment process by conducting experiments on both a bistable and a monostable boom. Lastly, we performed deployment tests on a free-floating platform, which emulates a small satellite, to quantitatively measure the attitude perturbations caused by the rapid deployment of the boom.对于先进的太空任务来说，既要满足增加有效载荷体积的要求，又要尽量减小航天器的体积，这可以通过利用可展开结构来实现。在之前的一项研究中，我们从完全展开时的姿态与弹性动力学之间的相互作用角度对薄壁吊杆进行了表征。在当前的工作中，我们开发了一个数值模型来分析展开过程的关键阶段。我们将该模型的预测结果与理论预期和实验数据进行了比较，发现两者之间具有很强的一致性。此外，我们还通过在双稳态和单稳态吊杆上进行实验，研究了双稳态对布放过程的影响。最后，我们在一个模拟小型卫星的自由浮动平台上进行了布放测试，以定量测量快速布放吊杆所造成的姿态扰动。Composites Part A: Applied Science and ManufacturingEnhanced interlaminar fracture toughness of unidirectional CFRP laminates with tailored microstructural heterogeneity of toughening layerOu Yunfu, Fu Anran, Wu Longqiang, Yi Xiaosu, Mao Dongshengdoi:10.1016/j.compositesa.2023.107872增韧层的微结构异质性可增强单向 CFRP 层压板的层间断裂韧性This work detailed a novel hierarchical Carbon fiber/CNT/Epoxy composites with tailored microstructural heterogeneity of toughening layer. The heterogeneity in the toughening layer of these laminates was engineered during spray coating process by controlling the length and content of CNT to produce CNT aggregated particles with spatial separation. Each particle contains a number of CNT and is managed to have controlled sizes. The concept of “CNT particle toughening” was firstly proposed and confirmed, opening a new way to fully enable the exploitation of the toughening potential of CNT. The effectiveness and efficiency of this technique are demonstrated by using the extremely low CNT content (0.3 gsm) to achieve remarkable improvements of the Mode-I and Mode-II interlaminar fracture toughness, which are 168% and 155%, respectively.这项研究详细介绍了一种新型分层碳纤维/CNT/环氧树脂复合材料，其增韧层的微观结构具有定制的异质性。这些复合材料增韧层的异质性是在喷涂过程中通过控制碳纳米管的长度和含量来产生具有空间分隔的碳纳米管聚集颗粒的。每个颗粒都包含一定数量的碳纳米管，并且大小可控。首次提出并证实了 "CNT 颗粒增韧 "的概念，为充分发挥 CNT 的增韧潜力开辟了一条新途径。通过使用极低的 CNT 含量（0.3 gsm）来显著提高模式 I 和模式 II 层间断裂韧性（分别为 168% 和 155%），证明了该技术的有效性和效率。Composites Science and TechnologyScalable, roll-to-roll manufacturing of multiscale nanoparticle/fiber composites using electrophoretic deposition: Novel multifunctional in situ sensing applicationsSung Dae Han, Doshi Sagar M., Rider Andrew N., Kimble Evan, Martin Robert, Ahmed Mohammad T., Thostenson Erik T.doi:10.1016/j.compscitech.2023.110322 利用电泳沉积技术实现多尺度纳米粒子/纤维复合材料的可扩展卷对卷制造：新型多功能原位传感应用Multiscale composites, where traditional fiber reinforcements are combined with nanoscale reinforcements, have emerged as multifunctional materials and have found potential for in situ strain and damage sensing, and energy harvesting/storage applications. Critical to the advancement of future applications is the development of manufacturing techniques that are industrially scalable. Electrophoretic deposition (EPD) can uniformly coat functionalized nanoparticles, such as carbon nanotubes (CNT), on conductive and non-conductive fiber substrates, producing multiscale composites with controlled microstructures and functional properties. In this research, a pilot-scale roll-to-roll EPD system is developed to continuously manufacture CNT-integrated fabrics for in situ sensing applications. Based on fundamental knowledge of CNT deposition mechanisms, key experiments are conducted to determine electrode configurations to optimize deposition yield in the roll-to-roll process. Functionalized CNTs are then deposited on 4–6 m long continuous rolls of randomly oriented non-woven glass fiber veil with different areal weights, and the CNTs form a continuous, conductive fiber-level coating. The thin and open fabric microstructure allows embedded sensors that are minimally invasive to the composite structure and allow ultraviolet (UV) light transmittance for use with UV-curable resins. The electrically conductive CNT network created on the fabric allows for the integration of sensing functionality. Short beam specimens with the CNT sensors embedded at the midplane showed no deterioration in strength. Multiple functionalities, including strain sensing and flow/UV cure monitoring during vacuum infusion are demonstrated. Sensors tested under flexural loading demonstrated sensitivity in tension and compression, and during resin infusion, the sensors could track resin flow and cure progression.传统纤维增强材料与纳米级增强材料相结合的多尺度复合材料已成为一种多功能材料，在现场应变和损伤传感以及能量收集/存储应用方面具有潜力。推动未来应用的关键是开发可工业化扩展的制造技术。电泳沉积（EPD）可以将碳纳米管（CNT）等功能化纳米粒子均匀地涂覆在导电和非导电纤维基底上，生产出具有可控微结构和功能特性的多尺度复合材料。本研究开发了一种试验规模的辊对辊 EPD 系统，用于连续生产原位传感应用中的 CNT 集成织物。基于对碳纳米管沉积机制的基本了解，本研究进行了关键实验，以确定电极配置，优化卷对卷工艺中的沉积产量。然后，将功能化碳纳米管沉积在 4-6 米长、不同单位重量的随机取向无纺玻璃纤维纱连续卷筒上，碳纳米管形成连续的导电纤维级涂层。这种薄而开放的织物微结构允许嵌入传感器，对复合结构的影响极小，并具有紫外线（UV）透射率，可与紫外线固化树脂配合使用。织物上形成的导电 CNT 网络可以集成传感功能。在中面上嵌入 CNT 传感器的短梁试样强度没有下降。该产品具有多种功能，包括应变传感和真空灌注过程中的流量/紫外固化监测。在挠曲载荷下测试的传感器显示了拉伸和压缩灵敏度，在树脂灌注过程中，传感器可以跟踪树脂的流动和固化进程。An ultra-thin composite electrolyte with vertical aligned Li ion transport pathways for all-solid-state lithium metal batteryChen Xiaobin, Liao Wenchao, Chen Dazhu, Huang Yanfei, Liu Chendoi:10.1016/j.compscitech.2023.110327 用于全固态锂金属电池的具有垂直排列锂离子传输通道的超薄复合电解质All-solid-state lithium metal batteries employing composite electrolytes can fundamentally settle the safety issues of commercial liquid electrolytes. However, the thick thickness and low ionic conductivity as well as unregulated ion transport of current composite electrolytes pose great obstacles in further promoting their applicability and compatibility with Li metal anode. Herein, an ultra-thin composite electrolyte with vertical aligned Li ion transport pathways is rationally designed via filling polyethylene glycol-perfluoropolyether polymer electrolyte into the nanochannels of an alumina template via vacuum infusion and in-situ polymerization. The strong Lewis acid-base effect that existed between ions and composite electrolytes can construct numerous fast channels for Li+ transport. A restrained vertical direction of ion immigration can facilitate the uniform deposition of Li+ on metallic Li anode. The shortened Li ion conductive distance and superior electrolyte/electrode interfaces contribute to the improved electrochemical performance of the assembled solid-state batteries. An ionic conductivity of 1.21 × 10−4 S cm−1 and a transference number of 0.37 at room temperature are achieved for the designed composite electrolytes, which is superior to those of the conventional composite electrolytes reinforced with Al2O3 or garnet nanoparticles. The corresponding Li symmetrical cell can stably work for over 1200 h without short-circuit and the LiFePO4 || Li full cell exhibits a high initial discharge capacity of 164.8 mAh g−1 with capacity retention of 93.7 % after 100 cycles with a coulombic efficiency close to 100 %. This work offers an effective tactic to develop ultra-thin composite electrolytes for high-performance all-solid-state lithium metal batteries.采用复合电解质的全固态锂金属电池可以从根本上解决商用液态电解质的安全问题。然而，目前的复合电解质厚度厚、离子电导率低、离子传输不规范，这对进一步提高其适用性和与锂金属负极的兼容性构成了巨大障碍。本文通过真空灌注和原位聚合的方法，将聚乙二醇-全氟聚醚聚合物电解质填充到氧化铝模板的纳米通道中，合理设计了一种具有垂直排列锂离子传输通道的超薄复合电解质。离子与复合电解质之间存在的强路易斯酸碱效应可为 Li+ 传输构建大量快速通道。抑制离子的垂直迁移方向可促进 Li+ 在金属锂阳极上的均匀沉积。缩短的锂离子传导距离和优异的电解质/电极界面有助于提高组装固态电池的电化学性能。所设计的复合电解质在室温下的离子电导率为 1.21 × 10-4 S cm-1，转移数为 0.37，优于用 Al2O3 或石榴石纳米颗粒增强的传统复合电解质。相应的锂对称电池可稳定工作 1200 小时以上而不发生短路，LiFePO4 || Li 全电池的初始放电容量高达 164.8 mAh g-1，循环 100 次后容量保持率为 93.7%，库仑效率接近 100%。这项研究为开发用于高性能全固态锂金属电池的超薄复合电解质提供了一种有效的方法。来源：复合材料力学仿真Composites FEM