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【新文速递】2024年6月10日复合材料SCI期刊最新文章

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今日更新:Composite Structures 6 篇,Composites Part A: Applied Science and Manufacturing 2 篇,Composites Part B: Engineering 1 篇,Composites Science and Technology 1 篇

Composite Structures

Predicting the mixed-mode fracture propagation in single-leg bending using a radial point interpolation meshless method

D.C. Gonçalves, L.D.C. Ramalho, R.D.S.G. Campilho, J. Belinha

doi:10.1016/j.compstruct.2024.118270

用无网格径向点插值法预测单腿弯曲混合模式断裂扩展

Adhesive bonding is a widely used joining technique with increasing applications in the automotive and aircraft industries. However, the numerical simulation of adhesively bonded joints is challenging due to the intricate mechanical behavior of the bonding layer, especially when structures are subjected to mixed-mode loading. This work proposes a meshless fracture propagation algorithm to simulate mixed-mode fracture propagation in single-leg bending (SLB) adhesive joints. The proposed algorithm combines the radial point interpolation method (RPIM) with a mixed-mode strain-based criterion to predict crack growth. The RPIM permits a flexible discretization of the fracture region and eases the geometric remeshing of the integration cells to account for the crack tip propagation. Additionally, the RPIM provides accurate and smooth strain/stress fields, allowing implementation of the mixed-mode fracture criterion. The numerical model was validated against experimental data for SLB adhesive joints with a brittle adhesive. The results showed that the proposed algorithm can accurately predict the resistance curves and critical energy release rates of the adhesive joints.

粘接是一种应用广泛的连接技术,在汽车和飞机工业中的应用越来越广泛。然而,由于粘接层复杂的力学行为,特别是当结构受到混合模式加载时,粘接接头的数值模拟具有挑战性。本文提出了一种无网格断裂扩展算法来模拟单腿弯曲(SLB)粘接接头的混合模式断裂扩展。该算法将径向点插值法(RPIM)与基于应变的混合模式准则相结合来预测裂纹扩展。RPIM允许对断裂区域进行灵活的离散化,并简化了积分单元的几何网格划分,以考虑裂纹尖端的扩展。此外,RPIM提供准确、平滑的应变/应力场,允许实现混合模式断裂准则。对带有脆性胶粘剂的SLB胶粘剂接头进行了数值模拟和实验验证。结果表明,该算法能较准确地预测粘接接头的阻力曲线和临界能量释放率。


Modal characteristics of functionally graded porous Timoshenko beams with variable cross-sections

V.N. Burlayenko, H. Altenbach, S.D. Dimitrova

doi:10.1016/j.compstruct.2024.118273

变截面功能梯度多孔Timoshenko梁的模态特性

The study focuses on the free vibration analysis of beams composed of functionally graded porous materials and characterized by a variable cross-section along their length. A broad range of beams is examined encompassing various tapered configurations, porosity profiles, and porosity content. The equations of motion are derived using Hamilton’s principle within the framework of Timoshenko beam theory. These equations are solved semi-analytically using the differential transform method, which has been adapted to incorporate various boundary conditions such as clamped-clamped, clamped-free, clamped-pinned, and pinned-pinned constraints within a general formulation of the beam eigenvalue problem. To validate the proposed solution technique, computed natural frequencies are compared with existing literature results for tapered inhomogeneous beams and uniform porous beams. Notably, new results are obtained for tapered porous beams. In this regard, a comprehensive parametric study explores the influence of various factors on the natural frequencies and mode shapes of functionally graded porous beams with variable cross-sections. These factors include the type of porosity profiles, a range of porosity parameters, cross-section taper ratios, and specific boundary conditions. The findings deepen our understanding of the modal characteristics of functionally graded porous beams, providing valuable guidance for engineering design and structural optimization in relevant applications. Additionally, they may serve as benchmarks for other researchers.

研究了由功能梯度多孔材料组成的具有变截面特征的梁的自由振动分析。广泛的梁被检查包括各种锥形配置,孔隙率剖面和孔隙率含量。在铁木辛柯梁理论的框架内,利用哈密顿原理推导出运动方程。这些方程是用微分变换方法半解析地解决的,该方法已被适应于在梁特征值问题的一般公式中纳入各种边界条件,如夹紧-夹紧,无夹紧,夹紧-固定和夹紧-固定约束。为了验证所提出的求解方法,将计算的固有频率与已有文献中锥形非均匀梁和均匀多孔梁的计算结果进行了比较。值得注意的是,对于锥形多孔梁,得到了新的结果。在这方面,一项全面的参数研究探讨了各种因素对变截面功能梯度多孔梁的固有频率和模态振型的影响。这些因素包括孔隙度剖面类型、孔隙度参数范围、截面锥度比和特定的边界条件。研究结果加深了我们对功能梯度多孔梁模态特性的理解,为相关应用的工程设计和结构优化提供了有价值的指导。此外,它们可以作为其他研究人员的基准。


Three-dimensional heat transfer analysis of Hot Gas Torch (HGT)-assisted Automated Fiber Placement (AFP) for thermoplastic composites

Lorenz Zacherl, Allyson Fontes, Farjad Shadmehri

doi:10.1016/j.compstruct.2024.118256

热塑性复合材料热气体火炬(HGT)辅助自动铺放纤维(AFP)的三维传热分析

Automated Fiber Placement (AFP) is a key additive manufacturing process for the production of complex composite structures. This study focuses on the in-situ AFP process for thermoplastic composites with Hot Gas Torch (HGT), which includes heating, consolidation, and solidification steps. Temperature control is critical to achieving high quality parts as it affects bond quality, crystallization, and solidification. However, previous studies have oversimplified convective heat transfer by assuming a constant coefficient, resulting in discrepancies between simulations and experiments. This paper introduces a novel distribution function to model the convective heat transfer coefficient, thereby improving temperature predictions. An optimization loop is used to determine the parameters of the function, which ensures agreement with experimental data. The proposed approach accurately predicts the temperature distribution, which is validated against unseen experimental results. By incorporating the distribution of the convective heat transfer coefficient, this study improves the understanding of heat transfer mechanisms in AFP for thermoplastic composites, leading to improved manufacturing processes and part quality.

自动铺放纤维(AFP)是复杂复合材料结构生产的关键增材制造工艺。本文主要研究了热塑性复合材料的热气体火炬原位AFP工艺,包括加热、固结和凝固步骤。温度控制是获得高质量零件的关键,因为它影响粘结质量、结晶和凝固。然而,以往的研究假设对流换热系数为常数,对对流换热进行了过度简化,导致模拟结果与实验结果不一致。本文引入了一种新的分布函数来模拟对流换热系数,从而提高了对温度的预测。利用优化循环确定函数参数,保证了与实验数据的一致性。该方法准确地预测了温度分布,并与未见的实验结果进行了验证。通过结合对流换热系数的分布,本研究提高了对热塑性复合材料AFP中传热机制的理解,从而改善了制造工艺和零件质量。


Chaotic snap-through vibrations of bistable asymmetric deployable composite laminated cantilever shell under foundation excitation and application to morphing wing

W. Zhang, L.L. Ren, Y.F. Zhang, X.T. Guo

doi:10.1016/j.compstruct.2024.118261

基础激励下双稳态非对称可展开复合材料层状悬臂壳的混沌破断振动及其在变形翼上的应用

The realization of the dynamic snap-through behaviors provides the new design ideas in the fields of the morphing aircraft and piezoelectric energy harvesting. This paper studies 1:2 internal resonance, nonlinear vibrations and chaotic snap-through phenomena of the bistable asymmetric composite laminated (BSCL) cantilever shell with the lower-frequency and higher-frequency primary resonances for the first time. The transverse foundation excitation subjects to the fixed end of the bistable cantilever shell. The perturbation analysis of two-degrees-of-freedom nonlinear ordinary differential equations is carried out by using the first-order approximate multiple scale method. The analytical results of the frequency-amplitude and force-amplitude response curves are obtained under the small foundation excitation. The obtained results reveal that the BSCL cantilever shell exhibits the double-jumping characteristics when 1:2 internal and primary resonances occur. There is a continuous energy exchange back and forth between two modes of the bistable laminated cantilever shell. As the foundation excitation increases, the BSCL cantilever shell exhibits saturation phenomenon. Numerical simulations are finished to further investigate the effects of the large excitation on the chaotic, quasi-periodic and snap-through vibrations for the BSCL cantilever shell. The vibration experiment is carried out to investigate the internal resonance and dynamic snap-though motions of the BSCL cantilever shell. Using the snap-though behaviors of the BSCL cantilever shell, we obtain the morphing structure of the aircraft wing.

动态通断行为的实现为变形飞行器和压电能量收集等领域的设计提供了新的思路。本文首次研究了具有低频和高频主共振的双稳态不对称复合材料层合层(BSCL)悬臂壳的1:2内共振、非线性振动和混沌卡断现象。横向基础激励受双稳悬臂壳固定端的影响。采用一阶近似多尺度法对两自由度非线性常微分方程进行了摄动分析。得到了小基础激励下的频率-幅值和力-幅值响应曲线的解析结果。结果表明,BSCL悬臂壳在发生1:2内共振和主共振时具有双跳变特性。双稳层合悬臂壳的两种模态之间存在着连续的能量交换。随着地基激励的增加,BSCL悬臂壳出现饱和现象。通过数值模拟进一步研究了大激励对BSCL悬臂壳混沌振动、准周期振动和卡断振动的影响。通过振动试验研究了BSCL悬臂壳的内部共振和动态跳脱运动。利用BSCL悬臂壳的吸通特性,得到了飞机机翼的变形结构。


Experimental study on the vibrational response and damping of short fibre/unidirectional PEEK hybrid composites

James Pheysey, Natalia Mazancova, Francesco De Cola, David Garcia Cava, Francisca Martinez-Hergueta

doi:10.1016/j.compstruct.2024.118264

短纤维/单向PEEK杂化复合材料振动响应及阻尼的实验研究

This study investigates the vibrational performance of a new generation of hybrid composites based on a short fibre core for structural dynamic applications. The dynamic characterisation was conducted through dynamic mechanical analysis (DMA) and the free vibration of a cantilever beam at different lengths. The short fibre composite exhibited a superior specific damping capacity, producing a maximum damping of 0.42. The values extracted from DMA indicated no visco-plastic contribution from the PEEK resin system, implying that the internal microarchitecture drives the material damping, with friction at the fibre/matrix interface being the primary dissipation mechanism. The hybrid laminate presented an improvement in damping performance of 39% due to the addition of the short fibre core compared to a baseline quasi-isotropic laminate of similar flexural stiffness. These findings show hybridisation’s advantages in designing structural components with improved damping performance and reduced cost for a variety of dynamic applications in industries such as automotive.

本文研究了新一代基于短纤维芯的混合复合材料的振动性能。通过动态力学分析(DMA)和悬臂梁在不同长度下的自由振动进行了动态表征。短纤维复合材料表现出优越的比阻尼能力,产生的最大阻尼为0.42。从DMA中提取的值表明PEEK树脂体系没有粘塑性贡献,这意味着内部微结构驱动材料阻尼,纤维/基体界面的摩擦是主要的耗散机制。与具有相似抗弯刚度的基准准各向同性层压板相比,由于添加了短纤维芯,混合层压板的阻尼性能提高了39%。这些发现表明,混合动力在设计结构部件方面具有改善阻尼性能和降低成本的优势,适用于汽车等行业的各种动态应用。


Cyclic damage quantification in composite materials using discrete damage mechanics

Nikolay V. Turbin, Kirill A. Shelkov, Nikolai O. Kononov, Ever J. Barbero

doi:10.1016/j.compstruct.2024.118271

基于离散损伤力学的复合材料循环损伤量化

A method for fatigue damage quantification in composite materials, based on experimental stiffness degradation data for composite laminates subjected to cyclic load is proposed. Discrete damage mechanics theory is used to calculate crack density vs. number of cycles from elastic moduli-reduction data obtained during fatigue experiments. The calculated crack density simplifies fatigue testing by diminishing the need for counting cracks during testing. Accurate results are achieved and reported. The defect-nucleation rate, which controls the fatigue damage rate, is also obtained from processing the modulus-reduction data. It is observed that the defect-nucleation rate has a small scatter and is independent of applied load magnitude. Furthermore, the onset of delamination observed in the experiments correlates very well with the onset of deviation between the predicted and experimental curves of elastic moduli-reduction versus accumulated crack density. An additional parameter, the defect-nucleation threshold, is here proposed to further characterize the fatigue performance of the composite material under stress-controlled fatigue loading, in contrast to thermal fatigue results from the literature. Furthermore, the difference in damage nucleation rate between strain-controlled and stress-controlled was observed and discussed.

提出了一种基于循环载荷下复合材料层合板刚度退化实验数据的复合材料疲劳损伤量化方法。利用离散损伤力学理论,从疲劳试验中获得的弹性模量缩减数据计算裂纹密度与循环次数的关系。计算出的裂纹密度减少了试验中对裂纹计数的需要,从而简化了疲劳试验。获得并报告准确的结果。通过对模量折减数据的处理,得到了控制疲劳损伤速率的缺陷形核率。观察到缺陷成核率具有较小的散射,并且与外加载荷大小无关。此外,实验中观察到的分层开始与弹性模量缩减与累积裂纹密度的预测曲线和实验曲线之间的偏差开始非常相关。本文提出了一个额外的参数,即缺陷成核阈值,以进一步表征复合材料在应力控制疲劳载荷下的疲劳性能,与文献中的热疲劳结果形成对比。此外,还观察并讨论了应变控制与应力控制在损伤成核速率上的差异。


Composites Part A: Applied Science and Manufacturing

Failure envelope prediction of 2D SiCf/SiC composites based on XGBoost model

Ben Wang, Jingyu Zhao, Zaoyang Guo, Biao Wang

doi:10.1016/j.compositesa.2024.108287

基于XGBoost模型的二维SiCf/SiC复合材料失效包络线预测

In this paper, a multiple failure mechanisms-based progressive damage model is developed to capture the mechanical response and defect-induced nonlinear behavior of SiCf/SiC composites. This model is then adopted to simulate the stress–strain response of a representative volume element model under uniaxial loading, showing excellent agreement with experiments. The effects of the volume fraction of SiC fibers, as well as those of the porosity and microcrack density of SiC matrix, on the deformation and damage behavior of SiCf/SiC composites are predicted. Based on this, the failure envelopes related to micro-mesoscopic characteristics under combined loadings are generated as the database for the eXtreme Gradient Boosting (XGBoost) model training. Finally, a data-driven failure model is established for SiCf/SiC composites, whose prediction is compared with the formal failure criteria. The results demonstrate that the data-driven SiCf/SiC composite failure model is reliable in constructing the failure criteria related to micro-mesoscopic features.

为了研究SiCf/SiC复合材料的力学响应和缺陷非线性行为,建立了一种基于多破坏机制的渐进损伤模型。采用该模型对具有代表性的体元模型进行了单轴加载下的应力-应变响应模拟,结果与实验结果吻合良好。预测了SiC纤维体积分数、SiC基体孔隙率和微裂纹密度对SiCf/SiC复合材料变形和损伤行为的影响。在此基础上,生成组合载荷作用下与细观特征相关的失效包络,作为极限梯度增压(eXtreme Gradient boost, XGBoost)模型训练的数据库。最后,建立了SiCf/SiC复合材料的数据驱动失效模型,并将其预测结果与形式失效准则进行了比较。结果表明,数据驱动的SiCf/SiC复合材料破坏模型在构建与细观特征相关的破坏准则方面是可靠的。


A smart insulation material achieving self-reporting and autonomous repairing against electrical and mechanical damages based on targeted controllable microcapsules

Wenlong Pang, Wenxia Sima, Potao Sun, Tao Yuan, Ming Yang, Xiaoxiao Chen, Zhaoping Li

doi:10.1016/j.compositesa.2024.108299

一种基于目标可控微胶囊的智能绝缘材料,实现对电气和机械损伤的自我报告和自主修复

Under the long-term action of electrical and mechanical stresses, irreversible micro-damages, such as electrical trees and cracks tend to occur inside solid insulation materials, leading to insulation failures, which have no effective countermeasures. This study develops a multi-responsive, target-controlled microcapsule to endow the epoxy resin with dual functions of self-reporting and autonomous repair against internal damage even under strong electric fields without human intervention. A turn-on mechanism for self-reporting signals is designed, to be applicable to electrical tree damage inside an epoxy matrix. In situ UV emissions generated by the partial discharge during electrical treeing are employed to automatically cure the microcapsule core material released into the damaged channel. This triggers aggregation-induced emission (AIE) signals and simultaneously repairs the damaged matrix. The polyurethane hybrid shell filled with magnetic particles endows the microcapsules with magnetic response characteristics. Under the control of a directional magnetic field, the microcapsule is concentrated around the vulnerable areas, obtaining high fluorescence emission intensity under low doping content without affecting the matrix performance. This method enables the autonomous inspection and maintenance of electric equipment and electronic devices under live working and provides new insight into the bionic intelligence of electrical and electronic insulation materials.

在长期的电应力和机械应力作用下,固体绝缘材料内部容易出现电树、裂纹等不可逆的微损伤,导致绝缘失效,目前尚无有效的对策。本研究开发了一种多响应、靶标控制的微胶囊,使环氧树脂在强电场下无需人为干预,也具有自我报告和内部损伤自主修复的双重功能。设计了一种自我报告信号的开启机制,适用于环氧树脂基体内部的电气树损伤。利用电树过程中局部放电产生的原位紫外线辐射,自动固化释放到受损通道中的微胶囊芯材。这触发了聚集诱导发射(AIE)信号,同时修复了受损的基质。填充磁性颗粒的聚氨酯复合壳使微胶囊具有磁响应特性。在定向磁场的控制下,微胶囊在脆弱区域周围集中,在低掺杂含量下获得高荧光发射强度,而不影响基体性能。该方法实现了带电工作下电气设备和电子设备的自主检测和维护,为电气和电子绝缘材料的仿生智能提供了新的见解。


Composites Part B: Engineering

Smart Polymer Composites with Vertically Oriented Boron Nitride and Carbon Fiber for Heat Management: Magneto-Thermal Responsiveness

Fang Peng, Yuting Song, Tongle Xu, Menghuan Wang, Na Song, Sheng Sun, Peng Ding

doi:10.1016/j.compositesb.2024.111617

智能聚合物复合材料与垂直取向氮化硼和碳纤维热管理:磁热响应

Emerging structural materials for aerospace deformable structures, soft robotics, and advanced smart electronic devices necessitate reversible, lockable, and reprogrammable shape transformation capabilities. A challenge in this realm is heat accumulation in high-power density devices, which limited impedes broader applications of these materials. This study introduces magneto-thermal coupling response and efficient heat dissipation to structural composite, facilitating reversible and reprogrammable material deformation. Our composites prepared using bi-directional freeze casting strategy demonstrated excellent thermal management capabilities. When the composites were applied to the chip heat dissipation, the chip temperature was significantly reduced by 36.3 °C from 112.2 °C. Furthermore, the integration of a flexible boron nitride nanosheets (BNNS)/carbon fibers (CFs) network with magnetic Fe3O4 particles and phase-change material enables effective magneto-thermal response. This magnetically controlled thermal deformation behavior of composites provides a promising avenue for the development of multimodal morphing structures for soft robotics and aerospace applications.

用于航空航天可变形结构、软机器人和先进智能电子设备的新兴结构材料需要可逆、可锁定和可重新编程的形状转换能力。这一领域的一个挑战是高功率密度器件的热积累,这限制了这些材料的广泛应用。本研究将磁-热耦合响应和高效散热引入结构复合材料,促进可逆和可编程材料变形。我们采用双向冷冻铸造策略制备的复合材料表现出出色的热管理能力。当复合材料应用于芯片散热时,芯片温度从112.2℃显著降低36.3℃。此外,柔性氮化硼纳米片(BNNS)/碳纤维(CFs)网络与磁性Fe3O4颗粒和相变材料的集成可以实现有效的磁热响应。这种磁控复合材料的热变形行为为软机器人和航空航天应用的多模态变形结构的发展提供了一条有前途的途径。


Composites Science and Technology

Enhanced interfacial interaction of graphene nanoplatelets/cellulose nanofiber matrix driven by pyranine-based dispersant for efficient thermal managing materials

Yoojung Choi, Jae Hun Kim, Hyunseong Shin, Seong Dae Park, Hyunseung Yang

doi:10.1016/j.compscitech.2024.110698

 

pyranine分散剂驱动的石墨烯纳米片/纤维素纳米纤维基质界面相互作用增强,用于高效热管理材料

With the development of high-density electronics, polymer-based thermal conductive composites with excellent thermal and mechanical performance are receiving great attention. For the development of polymer-based thermal conductive composites with superior properties, it is essential to reduce the agglomeration of fillers and enhance the interfacial interactions between thermal conductive fillers and the polymer matrix. Among the several thermal conductive materials, graphene nanoplatelets (GNPs) and cellulose nanofiber (CNFs) are attracting attention. However, poor interfacial interaction between GNP and CNF leads to interfacial separation, which in turn, deteriorates its properties. Herein, we synthesized a pyranine-functionalized polyether dispersant (PyPE), which can significantly improve the interfacial interactions between GNPs and CNFs. The effect of PyPE on the dispersion behavior of GNPs and the thermomechanical properties of GNP-CNF composite were monitored. Furthermore, we also performed molecular dynamics (MD) simulations to investigate the impact of applying PyPE dispersant on the interfacial interactions between the GNP and CNF matrix. The application of PyPE significantly enhanced the dispersibility of GNPs within the CNF matrix, resulting in a 15.5% increase in-plane thermal diffusivity and a 24.5% enhancement in tensile strength of the composite, demonstrating their potential applications in high power density electrical equipment and electronic devices.

随着高密度电子技术的发展,具有优异热学性能和力学性能的聚合物基导热复合材料日益受到人们的重视。为了开发性能优越的聚合物基导热复合材料,必须减少填料的团聚,增强导热填料与聚合物基体之间的界面相互作用。在几种导热材料中,石墨烯纳米片(GNPs)和纤维素纳米纤维(CNFs)备受关注。然而,GNP与CNF之间的界面相互作用较差,导致界面分离,从而使其性能恶化。在此,我们合成了一种吡啶功能化聚醚分散剂(pyranne -功能化聚醚分散剂),它可以显著改善GNPs和CNFs之间的界面相互作用。考察了PyPE对GNPs分散行为和GNP-CNF复合材料热力学性能的影响。此外,我们还进行了分子动力学(MD)模拟,以研究应用PyPE分散剂对GNP和CNF矩阵之间界面相互作用的影响。PyPE的应用显著增强了CNF基体内GNPs的分散性,使复合材料的面内热扩散率提高了15.5%,抗拉强度提高了24.5%,显示了其在高功率密度电气设备和电子器件中的潜在应用。


来源:复合材料力学仿真Composites FEM
MeshingACTMechanicalAdditiveSystem振动疲劳断裂复合材料非线性航空航天汽车电子增材裂纹电场理论材料
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【新文速递】2024年11月6日复合材料SCI期刊最新文章

今日更新:Composite Structures 1 篇,Composites Part A: Applied Science and Manufacturing 2 篇,Composites Part B: Engineering 1 篇,Composites Science and Technology 5 篇Composite StructuresA multi-linear constitutive relation considering the temperature effect on quasi-static mode I delamination in UD/MD laminatesLuohuan Zou, Yu Gong, Dingli Tian, Yuting Gao, Jianyu Zhang, Libin Zhao, Ning Hudoi:10.1016/j.compstruct.2024.118691考虑温度对UD/MD层合板准静态I型分层影响的多线性本构关系In this study, a multi-linear constitutive relation taking into account temperature and fiber bridging is proposed for characterizing delamination behavior in composite laminates under various temperature conditions. An approach combining analytical solution and J-integral is also established for determining the cohesive parameters in the multi-linear constitutive relation. To validate the proposed constitutive relation, mode I quasi-static delamination experiments of unidirectional (UD) and multidirectional (MD) carbon/bismaleimide laminates are carried out at 25 ℃ (room temperature), 80 °C and 130 ℃. The experimental results show that the increasing temperature resulted in a monotonic increase in the fracture toughness of the UD laminates while affect the fracture toughness of MD laminates slightly. A FE model is established with the implementation of the proposed multi-linear constitutive relation using UMAT subroutine. Good agreements between the experimental and simulated results demonstrate the validity of the proposed constitutive relation, with the relative difference of peak load between predicted and experimental values less than 8.2 % and the relative difference of initial and steady-state fracture toughness between predicted and tested results less than 15 %. This study provides the possibility to numerically study the temperature effect on the delamination behavior of laminates and has promising applications in the damage tolerance design of composite structures.在这项研究中,提出了考虑温度和纤维桥接的多线性本构关系来表征复合材料层合板在不同温度条件下的分层行为。建立了解析解与j积分相结合的方法来确定多线性本构关系中的内聚参数。为了验证所提出的本构关系,在25℃(室温)、80 ℃和130℃下,对单向(UD)和多向(MD)碳/双马来酰亚胺层叠板进行了I型准静态分层实验。实验结果表明,温度升高导致UD层合板的断裂韧性单调增加,而对MD层合板的断裂韧性影响较小。利用UMAT子程序实现所提出的多线性本构关系,建立了有限元模型。试验结果与模拟结果吻合较好,验证了本构关系的有效性,峰值荷载预测值与试验值的相对差值小于8.2 %,初始断裂韧性和稳态断裂韧性预测值与试验值的相对差值小于15 %。该研究为数值研究温度对层合板分层行为的影响提供了可能,在复合材料结构的损伤容限设计中具有很好的应用前景。Composites Part A: Applied Science and ManufacturingCombination of in-/and ex-situ damage detection methods to investigate the forming behavior of fiber-metal-laminatesFlorian Thum, Marco Korkisch, Anna Trauth, Markus G.R. Sausedoi:10.1016/j.compositesa.2024.108562结合原位和非原位损伤检测方法研究金属纤维层合板的成形行为In this study, the forming behavior of fiber-metal laminates (FML) is investigated by a combination of different (in- and ex-situ) measurement techniques. Using FML-samples consisting of aluminum and carbon fiber reinforced polyamide-6, deep-drawing tests were employed at high temperatures. It can be concluded a conventional approach based on the forming limit curve (FLC) is not suitable to predict the failure initiated in the multi-material setup as principal strains cannot differentiate the strain in aluminum and CFRP and lack sensitivity to detect other relevant failure modes, such as debonding as well as debonding in between layers. To better understand the failure behavior due to forming of FML, an experimental setup, that based on the Nakajima-test, was developed, using in-situ acoustic emission testing, 3D digital image correlation as well as ex-situ X-ray computed tomography. The combined results from all methods helped to gain a deeper insight into how thermoplastic FML behave during deep drawing at elevated temperatures especially focusing on evolving damage inside the hybrid material在本研究中,通过不同(原位和非原位)测量技术的组合,研究了纤维-金属层压板(FML)的成形行为。采用由铝和碳纤维增强聚酰胺-6组成的fml样品,在高温下进行深拉试验。结果表明,基于成形极限曲线(FLC)的传统方法不适合预测多材料结构中引发的破坏,因为主应变不能区分铝和碳纤维布的应变,并且缺乏检测其他相关破坏模式(如脱粘和层间脱粘)的灵敏度。为了更好地了解FML形成的破坏行为,基于nakajima试验,开发了一种实验装置,使用原位声发射测试,3D数字图像相关以及非原位x射线计算机断层扫描。所有方法的综合结果有助于更深入地了解热塑性FML在高温深拉伸过程中的行为,特别是关注混合材料内部的演变损伤Effect of soft magnetic particles content on multi-physics field of magnetorheological composite gel clutch with complex flow channel excited by Halbach array arrangementGuang Zhang, Jiahao Luo, Min Sun, Yang Yu, Jiong Wang, Bo Chen, Qing Ouyang, Ye Qiu, Guinan Chen, Teng Shen, Zheng Zhangdoi:10.1016/j.compositesa.2024.108576软磁颗粒含量对Halbach阵列激发复杂流道磁流变复合凝胶离合器多物理场的影响In this paper we investigate the influence of soft magnetic particle mass fraction on the multi-physics field of proposed magnetorheological (MR) gel clutch. A novel MR gel clutch with complex cup-shaped gap is described, whose performance is based on the relative placement between Halbach array arrangement and MR gel. Smart MR gel with 40 wt%, 50 wt%, 60 wt%, 70 wt% and 80 wt% of soft magnetic particles used as the transfer medium and Halbach array is adopted as magnetic excitation system. Its magnetic/mechanical analysis is carried out based on Bingham-plastics model using COMSOL Multiphysics software, which takes into account the variation of dynamic viscosity with magnetic flux density. The distribution of the magnetic flux density, shear yield stress, post-yield viscosity, shear stress and torque in the four flow channels during the transition from engagement state to disengagement state are obtained and analyzed in detail. Multi-physics field characteristics of proposed MR gel clutch with five kinds of MR gels are studied and compared in order to give some useful suggestions in the design phase. Finally, the dynamic torque of the MR clutch with different MR gel is experimentally evaluated.本文研究了软磁颗粒质量分数对磁流变(MR)凝胶离合器多物理场的影响。介绍了一种新型的具有复杂杯状间隙的磁流变凝胶离合器,其性能基于哈尔巴赫阵列与磁流变凝胶的相对位置。采用40 wt%、50 wt%、60 wt%、70 wt%和80 wt%软磁颗粒的智能磁共振凝胶作为传递介质,采用Halbach阵列作为磁激励系统。采用COMSOL Multiphysics软件基于bingham -plastic模型对其进行了磁/力学分析,考虑了动态粘度随磁通密度的变化。得到并详细分析了从接合状态到脱离状态过渡过程中四个流道的磁通密度、剪切屈服应力、后屈服粘度、剪切应力和转矩的分布。对所提出的5种MR凝胶离合器的多物理场特性进行了研究和比较,以期在设计阶段提供一些有用的建议。最后,对不同磁流变凝胶的磁流变离合器的动态转矩进行了实验评估。Composites Part B: EngineeringScalable production of robust and creep resistant ultra-high filled wood-plastic compositesAn Yang, Zhengyu Liao, Zesheng Xu, Tian Liu, Yiqun Fang, Weihong Wang, Min Xu, Yongming Song, Qingwen Wang, Yao Lidoi:10.1016/j.compositesb.2024.111937 可扩展生产的坚固和抗蠕变超高填充木塑复合材料With the widespread use of wood-based materials in human life, the availability of wood resources has gradually decreased. The use of low-value wood that does not require chemical adhesives can address the depletion of wood resources used to prepare wood-based composites. However, the development of high-strength, low-cost, scalable wood-based composites from low-value wood is challenging. In this study, high-performance ultra-high filled wood-plastic composites (UFWPC) composed of up to 95 wt.% wood flour were prepared through cell wall densification and the construction of multiple cross-linked networks via deep cross-fusion. The UFWPC exhibited excellent mechanical properties, with a flexural strength that was 5.9 times higher than that of commercial particleboard, 2.1 times higher than commercial fiberboard, and 2.6 times higher than commercial wood-plastic composites. UFWPC also demonstrated excellent creep resistance, with a creep strain 76.79% lower than that of commercial wood-plastic composites. Finally, a customizable large-scale commercial continuous flat-pressing system was established to produce UFWPC. The highly efficient preparation of UFWPC makes it an excellent alternative to commercial wood-plastic composites, particleboard, and fiberboard. This approach provides a promising valorization and sustainability method for recycling plastics and low-value wood.随着木质材料在人类生活中的广泛应用,木材资源的可用性逐渐减少。使用不需要化学粘合剂的低价值木材可以解决用于制备木基复合材料的木材资源枯竭的问题。然而,从低价值木材中开发高强度、低成本、可扩展的木基复合材料具有挑战性。在本研究中,通过细胞壁致密化和深度交叉融合构建多个交联网络,制备了由高达95% wt.%的木粉组成的高性能超高填充木塑复合材料(UFWPC)。UFWPC具有优异的力学性能,其抗弯强度比商用刨花板高5.9倍,比商用纤维板高2.1倍,比商用木塑复合材料高2.6倍。UFWPC还表现出优异的抗蠕变性能,其蠕变应变比商用木塑复合材料低76.79%。最后,建立了一套可定制的大型商用平压系统来生产UFWPC。UFWPC的高效制备使其成为商用木塑复合材料、刨花板和纤维板的优良替代品。这种方法为回收塑料和低价值木材提供了一种有前途的增值和可持续性方法。Composites Science and TechnologyOpen source tool for Micro-CT aided meso-scale modeling and meshing of complex textile composite structuresBin Yang, Yuwei Feng, Cédric Béguin, Philippe Causse, Jihui Wangdoi:10.1016/j.compscitech.2024.110940 Micro-CT辅助复杂纺织复合材料结构细观建模和网格划分的开源工具Volumetric image-based modeling of textile reinforcements and composites is favored over ideal geometric modeling because of its ability to represent complex structures in sufficient detail. Although several approaches were devised, there is still a scarcity of dedicated tools capable of effectively transferring pertinent information from images to high-fidelity models. This work presents the open source project, PolyTex, a Python-based object-oriented application that establishes a streamlined and reproducible workflow for such tasks. Dual kriging serves as the foundational theory for the parametric approach developed to represent, simplify, and approximate the morphology and topology of fiber tows. The code takes two types of input, either an explicit representation of tow geometry using point clouds or implicit representations, such as image masks representing fiber tows separately with grayscale values. Tailored APIs allow for smooth integration between PolyTex’s modeling capabilities and the simulation environments offered by OpenFOAM and Abaqus. Case studies on virtual testing of textile permeability were presented to demonstrate this capability. The modular and object-oriented design makes PolyTex a highly reusable and extensible tool that allows users to create a customized pipeline.基于体积图像的纺织增强材料和复合材料建模比理想的几何建模更受青睐,因为它能够足够详细地表示复杂的结构。虽然设计了几种方法,但仍然缺乏能够有效地将相关信息从图像传输到高保真模型的专用工具。本文介绍了开源项目PolyTex,这是一个基于python的面向对象应用程序,它为此类任务建立了一个流线型和可重复的工作流。双克里格是用来表示、简化和近似纤维束形态和拓扑的参数化方法的基础理论。代码接受两种类型的输入,一种是使用点云来显式表示纤维束的几何形状,另一种是隐式表示,比如用灰度值分别表示纤维束的图像掩模。定制的api允许PolyTex的建模功能与OpenFOAM和Abaqus提供的仿真环境之间的平滑集成。以纺织品透气性的虚拟测试为例,说明了该方法的可行性。模块化和面向对象的设计使PolyTex成为一个高度可重用和可扩展的工具,允许用户创建定制的管道。Ultra-high strength and flame retardant carbon aerogel composites with efficient electromagnetic interference shielding and superior thermal insulation via nano-repairing routeWei Wang, Chong Ren, Jiaxin Zheng, He Huang, Can Wu, Xiangyu Jin, Changqing Hong, Xinghong Zhangdoi:10.1016/j.compscitech.2024.110949 通过纳米修复途径,具有高效电磁干扰屏蔽和优异隔热性能的超高强度阻燃碳气凝胶复合材料Carbon aerogel composites (CAs) have received numerous attention for protection of aircraft due to their unique properties. However, the shrinkage mismatch between rigid fibers and carbon sources during carbonization dramatically weakens the performance of CAs, and no significant breakthroughs have been made. We propose a vacuum impregnation assisted nano-repairing (VINR) strategy to fabricate crack-free carbon fiber reinforced carbon aerogel (Cf/CA) composites with high strength, electromagnetic interference shielding and thermal insulation. The cross-confined, overlapping nano-CA particles greatly limits the shrinkage of the carbon source, conferring excellent mechanical properties to Cf/CA, and its compressive strength and modulus reaches 3.93 MPa and 69.96 MPa in XY direction and 2.03 MPa and 40.67 MPa in Z direction, respectively, at 5% strain. In addition, Cf/CA exhibits significant thermal insulation (0.054 W/(m·K) at 25 °C under air condition) and superior electromagnetic interference shielding properties (EMI SE is ∼48.52 dB at a thickness of ∼2 mm). Herein, the structurally optimized Cf/CA provides a promising solution for multi-effect protection for critical electronic devices of aircraft in special service environments.碳气凝胶复合材料(CAs)由于其独特的性能在飞机防护方面受到了广泛的关注。然而,碳化过程中刚性纤维与碳源之间的收缩失配严重削弱了碳纤维的性能,目前还没有取得重大突破。提出了一种真空浸渍辅助纳米修复(VINR)方法,制备具有高强度、屏蔽电磁干扰和隔热性能的无裂纹碳纤维增强碳气凝胶(Cf/CA)复合材料。交叉约束、重叠的纳米CA颗粒极大地限制了碳源的收缩,赋予Cf/CA优异的力学性能,在5%应变下,其抗压强度和模量在XY方向分别达到3.93 MPa和69.96 MPa,在Z方向分别达到2.03 MPa和40.67 MPa。此外,Cf/CA具有显著的隔热性能(25°C空调条件下0.054 W/(m·K))和优异的电磁干扰屏蔽性能(EMI SE为~ 48.52 dB,厚度为~ 2mm)。因此,结构优化后的Cf/CA为特殊服役环境下飞机关键电子设备的多效保护提供了一种很有前景的解决方案。Expanded graphite encapsulation of nitrates for enhanced thermal transport: mechanism insight and component screeningKening Yan, Lin Qiu, Haimo Li, Ning Cao, Yanhui Fengdoi:10.1016/j.compscitech.2024.110957 硝酸盐的膨胀石墨封装增强热传输:机制的洞察力和成分筛选The efficient improvement of the heat transfer capability of high-temperature molten salts and the accurate measurement within the operating temperature range is vital for improving the efficiency of concentrating solar power devices. Through theoretical investigation, this paper explores different thermal properties including thermal conductivity, phase transition properties and interfacial interactions using a range of expanded graphite/nitrates (EG/nitrates). Molecular dynamics simulations reveal that the EG/eutectic salt (ES) exhibits optimal comprehensive properties. Experimentally prepared EG/ES composite phase change materials (PCMs), coupled with theoretical predictions, demonstrate exceptional thermal conductivity (2.2 W·m-1·K-1) and a significant latent heat of phase change (>80 J·g-1). The calculation results of the interaction energy between the host-guest indicate that the strong interaction of the EG to ES restricts the molecule movement, leading to a weak temperature dependence of the thermal conductivity of the EG/ES composite PCM. This contrasts with the conventional understanding of PCM thermal conductivity, which typically exhibits a sharp change during the phase transition from solid state to liquid state. Additionally, the thermal response of 15 wt% EG/ES is increased by 27.2% compared to pure ES, which effectively helps alleviate local overheating in practical applications. The progress made so far sheds light on the mechanism behind the improved heat transfer and storage performance of nitrate from a microscopic view, offering valuable theoretical insight for developing high-efficient nitrate PCMs in solar thermal power generation systems.有效提高高温熔盐的传热能力和在工作温度范围内的精确测量是提高聚光太阳能发电装置效率的关键。本文通过理论研究,探讨了一系列膨胀石墨/硝酸盐(EG/nitrates)的不同热性能,包括导热系数、相变性能和界面相互作用。分子动力学模拟表明,EG/共晶盐(ES)具有最佳的综合性能。实验制备的EG/ES复合相变材料(PCMs),结合理论预测,表现出优异的导热系数(2.2 W·m-1·K-1)和显著的相变潜热(>80 J·g-1)。主客体相互作用能的计算结果表明,EG与ES的强相互作用限制了分子的运动,导致EG/ES复合PCM的导热系数对温度的依赖性较弱。这与传统的对PCM热导率的理解形成了对比,传统的理解是PCM热导率在从固态到液态的相变过程中通常表现出急剧的变化。此外,与纯ES相比,15 wt% EG/ES的热响应提高了27.2%,有效地缓解了实际应用中的局部过热。目前所取得的进展从微观角度揭示了硝酸盐传热和储存性能改善背后的机制,为开发太阳能热发电系统中高效的硝酸盐pcm提供了有价值的理论见解。The critical role of size effect on internal damage and mechanical properties of flax fiber reinforced compositesLulu Lei, Yiqiao Zhao, Zefei Cheng, Jieyu Chen, Sixian Yang, Tao Yu, Jinhong Fan, Yan Li, Jianzhuang Xiaodoi:10.1016/j.compscitech.2024.110958 尺寸效应对亚麻纤维增强复合材料内部损伤及力学性能的影响The effect of the size on the strength of laminated artificial fiber reinforced composites has been extensive discussed during the design of large composites structure. With the trial as the structures in aerospace, civil engineering, automobile industry, the scaling of the properties of plant fiber reinforced composite should be studied. In this paper, the size effect and failure mechanism of tensile and impact properties of flax fiber reinforced composites were valuated. The effects of different area, thickness and volume on the tensile properties of composites were explored. Additionally, the failure mechanism of size effect on tensile specimens was proposed through the damage morphologies of composites. It is found that the twist of fiber bundle plays an important role in the size effect of composite thickness. Besides, the relationship between impact properties and size effect of composites was conducted, including the size of hammer, different impact energy and sample size. The curves of different types of impact samples were normalized to verify the linear rule in response stage. The crack length after impact was measured and the size effect of crack length was discussed. The size effect of crack area was studied by calculating the crack area with ultrasonic C-scan. Different “size effects” between flax fibers and artificial fibers were explored. The results are expected to provide a theoretical basis for the structural design of plant fiber reinforced composites.在大型复合材料结构设计中,广泛讨论了尺寸对层合人工纤维增强复合材料强度的影响。随着植物纤维增强复合材料在航空航天、土木工程、汽车工业等领域的应用,对其性能的影响问题进行了深入的研究。研究了亚麻纤维增强复合材料拉伸和冲击性能的尺寸效应及其破坏机理。探讨了不同面积、厚度和体积对复合材料拉伸性能的影响。此外,通过复合材料的损伤形态分析,提出了尺寸效应对拉伸试样的破坏机理。研究发现,纤维束捻度对复合材料厚度的尺寸效应有重要影响。此外,还分析了复合材料的冲击性能与尺寸效应之间的关系,包括锤头尺寸、不同冲击能和试样尺寸。对不同类型冲击试样的曲线进行归一化,验证了响应阶段的线性规律。测量了冲击后的裂纹长度,并讨论了裂纹长度的尺寸效应。通过超声c扫描计算裂纹面积,研究了裂纹面积的尺寸效应。探讨了亚麻纤维与人造纤维的不同“尺寸效应”。研究结果有望为植物纤维增强复合材料的结构设计提供理论依据。Bioinspired ultra-fine hybrid nanocoating for improving strength and damage tolerance of composite fan blades in flexible manufacturingXianhe Cheng, Qigang Han, Yuzhang Huang, Mingdi Shi, Hexuan Shi, Mengxue Ji, Chuncai Yangdoi:10.1016/j.compscitech.2024.110956 柔性制造中提高复合材料风扇叶片强度和损伤容忍度的仿生超细混合纳米涂层The ultrafine mineral bridges/bio-polymer hybrid structure inspired by nacreous is applied to the interface structure design of composite, aiming to address the high brittleness and low damage tolerance problems of carbon fiber composite fan blades (CFCFB). Herein, we present a simple and efficient approach, called the "cationic copolymer-mono micelle-mediated" method, to translate the nacre-inspired structure for developing micelles/ZnO hybrid nanocoating. The hybrid nanocoating was demonstrated to have remarkable characteristics such as ultrafine ZnO sizes, monodispersity, uniformity, and core-shell structure (diameters: ≈45 nm). Additionally, the coating process is simple, solvent-free, and seamlessly integrates with scalable carbon fiber manufacturing. Based on the nacre-inspired interface structure, the CFCFB exhibits high interlaminar strength (99.3 MPa), high stiffness (79 GPa), and high toughness (41.2 MPa m1/2). This study provides a blueprint for bioinspired ultrafine nanostructure design in composites and inspires advanced manufacturing strategies for other promising engineering materials.将珠蚌启发的超细矿物桥/生物聚合物杂化结构应用于复合材料界面结构设计,旨在解决碳纤维复合材料风扇叶片(CFCFB)的高脆性和低损伤容限问题。在此,我们提出了一种简单有效的方法,称为“阳离子共聚物-单胶束介导”的方法,来翻译纳米结构,以开发胶束/ZnO杂化纳米涂层。该杂化纳米涂层具有ZnO尺寸超细、单分散性、均匀性和核壳结构(直径≈45 nm)等显著特性。此外,涂层过程简单,无溶剂,并与可扩展的碳纤维制造无缝集成。基于珠核界面结构,CFCFB具有高层间强度(99.3 MPa)、高刚度(79 GPa)和高韧性(41.2 MPa m1/2)。该研究为仿生超细纳米复合材料的设计提供了蓝图,并为其他有前途的工程材料的先进制造策略提供了灵感。来源:复合材料力学仿真Composites FEM

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