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【新文速递】2024年3月28日复合材料SCI期刊最新文章

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今日更新:Composite Structures 4 篇,Composites Part A: Applied Science and Manufacturing 7 篇,Composites Part B: Engineering 1 篇,Composites Science and Technology 6 篇

Composite Structures

Damage evolution of CFRP laminates by normal and oblique impact erosion of pulsating water jets

Naidan Hou, Renxi Zhao, Yifan Yue, Xuan Wang, Hao Cui, Yulong Li

doi:10.1016/j.compstruct.2024.118079

脉动水射流正向和斜向冲击侵蚀 CFRP 层压板的损伤演变

Impact direction is one of the critical factors affecting the waterdrop erosion behavior of materials. In this paper, rain erosion damage behavior of a typical carbon fiber reinforced polymer (CFRP) laminate is investigated as a function of the impingement angle (0° as normal impact and 15°, 30°, 45° as oblique impact deviated from the normal) and the relative fiber orientation (parallel PA and perpendicular PE to the fiber direction of the surface layer) under the waterjet velocity of 320 m/s and the impact frequency of 50 Hz via a pulsating waterjet erosion test rig. After continuous impact of multiple waterjets, the typical damage of CFRP laminates is mainly composed of the central erosion crater and the upheaval of the surrounding surface layer. The onset and evolution of damage are mainly driven by the shear action of lateral jetting and stress concentration of hydraulic penetration exerted at the surface irregularities. There is no significant difference in the damage modes between the normal and oblique impacts, except for the asymmetric distributions of matrix cracking in PA-orientation and delamination in PE-orientation caused by the angle inclination. With the impingement angle increasing, the volume loss and erosion depth decrease while the incubation period increases mainly due to the decreases of water hammer pressure and contact area. The PA-orientation can cause lower incubation period and larger erosion mass loss than PE-orientation before the surface ply is penetrated, with the underlying mechanism related to the distinct tensile properties of CFRP laminates along longitudinal and transversal directions and the asymmetric properties of fiber–matrix interface. According to the fitting results of erosion curves, it is possible to describe the incubation period and the erosion rate of CFRP laminates under oblique impact using a two-branch equation, and Springer model can give reasonable prediction for the average incubation period and PA-orientation erosion rate of a certain oblique impact occasion with known 0° impact erosion results.

冲击方向是影响材料水滴侵蚀行为的关键因素之一。本文通过脉动水射流侵蚀试验台,研究了典型碳纤维增强聚合物(CFRP)层压板在水射流速度为 320 m/s、冲击频率为 50 Hz 条件下的雨水侵蚀破坏行为与冲击角度(0° 为正向冲击,15°、30°、45° 为偏离正向的斜向冲击)和相对纤维取向(平行于表层纤维方向的 PA 和垂直于表层纤维方向的 PE)的函数关系。在多次水射流的连续冲击下,CFRP 层压板的典型损伤主要由中心侵蚀坑和周围表层的动荡组成。损伤的发生和演变主要是由横向喷射的剪切作用和表面不规则处水力渗透的应力集中所驱动的。正向和斜向撞击的损伤模式没有明显差异,只是角度倾斜导致 PA 方向的基体开裂和 PE 方向的分层分布不对称。随着撞击角度的增大,体积损失和侵蚀深度减小,而潜伏期增加,这主要是由于水锤压力和接触面积减小。与 PE 取向相比,PA 取向在表面层被穿透之前会导致更短的潜伏期和更大的侵蚀质量损失,其根本机理与 CFRP 层压板沿纵向和横向的不同拉伸特性以及纤维-基质界面的非对称特性有关。根据侵蚀曲线的拟合结果,可以用一个双支方程来描述 CFRP 层压板在斜面冲击下的潜伏期和侵蚀率,Springer 模型可以在已知 0° 冲击侵蚀结果的基础上,合理预测特定斜面冲击场合的平均潜伏期和 PA 取向侵蚀率。


Multiscale analysis of composite pressure vessel structures wound with different fiber tensile force

Aleksander Błachut, Jerzy Kaleta, Jerzy Detyna, Barbara Kmiecik, Grażyna Ziętek, Maciej Panek, Mateusz Skoczylas

doi:10.1016/j.compstruct.2024.118065

以不同纤维拉力缠绕复合材料压力容器结构的多尺度分析

The aim of this paper is the multiscale investigation of composite pressure vessel structures wound with varying fibre tension. The paper explores the potential of ”programming” the fibre tension force during the winding process of a high pressure hydrogen storage vessel. Two series of vessels were wound with two different tensions: Two series of vessels wound with forces of 3 N and 80 N respectively were experimentally investigated. Other technological factors, such as the type and weight of carbon fibre used, were kept constant throughout the study. Quasi-static compression tests were used to measure the elastic deformation of the vessel surface. Microscopic studies were also carried out to analyse the structure of the composite at different length scales. The fibre content, the geometric parameters of the voids and the distribution of the three main components of the composite - carbon fibre, technological defects and resin - were also determined. Representative RVE elementary cells were generated for both materials using statistical modelling. The composite was then homogenised and elasticity matrices were obtained for the fibre tensile forces in both materials.

本文旨在对以不同纤维张力缠绕的复合材料压力容器结构进行多尺度研究。本文探讨了在高压储氢容器缠绕过程中对纤维张力进行 "编程 "的可能性。以两种不同的张力缠绕了两个系列的容器:实验研究了缠绕力分别为 3 N 和 80 N 的两个系列容器。在整个研究过程中,使用的碳纤维类型和重量等其他技术因素保持不变。准静态压缩试验用于测量容器表面的弹性变形。此外,还进行了显微研究,以分析复合材料在不同长度尺度上的结构。此外,还确定了纤维含量、空隙的几何参数以及复合材料三种主要成分(碳纤维、技术缺陷和树脂)的分布情况。利用统计建模生成了两种材料的代表性 RVE 基本单元。然后对复合材料进行均匀化处理,并获得两种材料中纤维拉力的弹性矩阵。


Dynamic crack growth in orthotropic brittle materials using an adaptive phase-field modeling with variable-node elements

Jianan He, Tiantang Yu, Weihua Fang, Sundararajan Natarajan

doi:10.1016/j.compstruct.2024.118068

利用带有可变节点元素的自适应相场建模在正交脆性材料中实现动态裂纹增长

In this paper, crack growth in orthotropic materials subjected to dynamic loading is numerically studied using an adaptive phase-field method. The study starts with a coarse structured mesh and the adaptive refinement strategy based on an user defined threshold on the phase-field variable is proposed for computational efficiency, and variable-node elements are employed to treat the hanging nodes as a result of local adaptive refinement. The Hughes-Hilbert-Taylor (HHT) time integration scheme is adopted for the temporal discretization. The directionality of orthotropic materials is represented by a penalized second-order structural matrix, which is incorporated in the crack face energy density. Through numerical examples, the influence of the material orientation on the dynamic crack growth in orthotropic materials is studied and the reliability of the proposed framework is validated.

本文采用自适应相场方法对承受动态载荷的各向同性材料的裂纹生长进行了数值研究。研究从粗结构网格开始,为提高计算效率,提出了基于用户定义的相场变量阈值的自适应细化策略,并采用变节点元素来处理局部自适应细化产生的悬挂节点。时间离散化采用休斯-希尔伯特-泰勒(HHT)时间积分方案。正交各向同性材料的方向性由惩罚性二阶结构矩阵表示,该矩阵被纳入裂纹面能量密度。通过数值实例,研究了材料方向性对正交材料动态裂纹生长的影响,并验证了所提框架的可靠性。


Multifunctional composite material based on piezoelectric nanofibers and Cu-CFRP electrodes for sensing applications

Francesco Mongioì, Giacomo Selleri, Tommaso Maria Brugo, Emanuele Maccaferri, Davide Fabiani, Andrea Zucchelli

doi:10.1016/j.compstruct.2024.118076

基于压电纳米纤维和铜-CFRP 电极的多功能复合材料在传感应用中的应用

To monitor possible failures of a composite, several Structural Health Monitoring (SHM) systems have been developed. However, these methods typically involve embedding commercial sensors within the laminate, potentially compromising the material's strength. In this study, a self-sensing composite laminate was fabricated by interleaving poly(vinylidenefluoride-trifluoroethylene) (P(VDF-TrFE)) piezoelectric nanofibers between Glass Fiber Reinforced Plastic (GFRP) prepreg plies. Instead of conventional metallic sheets, hybrid Copper-Carbon Fiber Reinforced Plastic (Cu-CFRP) was used as electrodes to collect piezoelectric signals. This innovative approach offers two main advantages: enhanced interlaminar fracture toughness due to nanometric piezoelectric fibers and an intrinsic connection between copper wires and carbon, eliminating the need for additional electrical cables within the laminate. The effect of stacking sequence parameters on the self-sensing laminate's electromechanical response was investigated using a Design of Experiment (DoE) based on the Box-Benken method. Additionally, a lumped electric circuit model was employed to gain analytical insights into the piezoelectric behavior of the laminates.

为了监测复合材料可能出现的故障,人们开发了多种结构健康监测(SHM)系统。然而,这些方法通常需要在层压板中嵌入商用传感器,这可能会影响材料的强度。在本研究中,通过在玻璃纤维增强塑料(GFRP)预浸料层之间交错聚(偏氟乙烯-三氟乙烯)(P(VDF-TrFE))压电纳米纤维,制造了一种自传感复合材料层压板。铜-碳纤维增强塑料(Cu-CFRP)混合材料取代了传统的金属片,被用作收集压电信号的电极。这种创新方法具有两大优势:纳米压电纤维增强了层间断裂韧性;铜线与碳之间的内在联系消除了层压板内的额外电线。我们采用基于方框-本肯(Box-Benken)方法的实验设计(DoE)研究了堆叠顺序参数对自感应层压板机电响应的影响。此外,还采用了叠加电路模型来分析层压板的压电行为。


Composites Part A: Applied Science and Manufacturing

Effects of through-thickness dielectric sensor on carbon fibre epoxy cure monitoring

Molly Hall, Xuesen Zeng, Tristan Shelley, Peter Schubel

doi:10.1016/j.compositesa.2024.108168

穿透厚度介电传感器对碳纤维环氧树脂固化监测的影响

Dielectric sensors are an appealing solution for in-situ cure monitoring of thermoset polymers and thermoset composites. Analysis techniques have been shown to produce highly accurate and repeatable insight into cure state metrics both during and after cure. However, most dielectric sensors only report data on the surface of the material the sensor is in direct contact with, neglecting the remainder of the thickness of the component. This study evaluates a novel dielectric sensor which is designed with a 20 mm penetration depth to monitor through the thickness of the composite part. While the prototype sensor design was shown to influence the raw data signal, a correction factor was successfully applied, and signals were analysed in accordance with the standard set of dielectric methods. The corrected signal had good accuracy and repeatability across laminates from 2 to 20 mm thick, demonstrating a non-invasive, through-thickness monitoring for a range of part designs.

电介质传感器是对热固性聚合物和热固性复合材料进行现场固化监测的一种极具吸引力的解决方案。分析技术已被证明能够在固化过程中和固化后对固化状态指标进行高精度和可重复的深入分析。然而,大多数介电传感器只能报告与传感器直接接触的材料表面的数据,而忽略了部件厚度的其余部分。本研究对新型介电传感器进行了评估,该传感器的设计穿透深度为 20 毫米,可监测复合材料部件的整个厚度。虽然原型传感器的设计会影响原始数据信号,但还是成功应用了校正因子,并根据标准介电方法对信号进行了分析。校正后的信号在厚度从 2 毫米到 20 毫米的层压板上都具有良好的准确性和可重复性,证明了可对各种部件设计进行非侵入式厚度监测。


Static and dynamic damping mechanical performance of architected metal-epoxy interpenetrating phase composites

Agyapal Singh, Nikolaos Karathanasopoulos

doi:10.1016/j.compositesa.2024.108171

 

架构金属-环氧互穿相复合材料的静态和动态阻尼机械性能

The present contribution investigates the static and dynamic damping mechanical response of architected aluminum-epoxy interpenetrating phase composites (IPCs), engineered with strut, triply periodic minimal surfaces (TPMS), and stochastic spinodal AlSi10Mg reinforcement phases. Both single-phase metamaterials and co-continuous, multi-phase composites are analyzed, assessing the role of the reinforcement phase design and the addition of silicon carbide (SiC) nano-whisker epoxy enhancements in the effective mechanical performance. Aluminum-epoxy IPCs yield a constitutive response with peak, plateau stress, and overall energy absorptions up to 25 times higher than the ones recorded for the underlying single-phase metamaterials. Inner plastic strains, probed through dedicated finite element analysis, provide insights into the inner damage evolution, leading to characteristic ductile failure patterns, as revealed by computer tomography analysis. The exceptional specific energy absorption attributes are complemented by outstanding dynamic performance characteristics, with significant loss moduli over a broad range of frequencies and damping ratios up to 0.29.

本论文研究了铝-环氧互穿相复合材料(IPCs)的静态和动态阻尼机械响应,该复合材料采用支杆、三重周期性最小表面(TPMS)和随机旋极 AlSi10Mg 增强相进行设计。分析了单相超材料和共连续多相复合材料,评估了增强相设计和添加碳化硅(SiC)纳米晶须环氧增强材料对有效机械性能的作用。铝-环氧 IPC 的峰值、高原应力和整体能量吸收的构成响应比底层单相超材料高出 25 倍。通过专门的有限元分析探究内部塑性应变,可以深入了解内部损伤的演变过程,从而形成计算机断层扫描分析所揭示的特征性韧性破坏模式。除了卓越的比能量吸收特性外,还具有出色的动态性能特征,在广泛的频率范围内具有显著的损耗模量,阻尼比高达 0.29。


Composite phase change materials with room-temperature-flexibility

Zaichao Li, Yuang Zhang, Xuan Wang, Feng Cao, Shufen Zhang, Bingtao Tang

doi:10.1016/j.compositesa.2024.108173

 

具有室温柔性的复合相变材料

Phase change materials (PCMs) have attracted considerable attention for effectively addressing the problem of thermal energy supply–demand mismatch. However, the practical application of PCMs is still hindered by inherent challenges such as crystalline rigidity, leakage susceptibility, and poor thermal conductivity. In this research, on the basic of thermal control provided by phase change storage and the elastic behavior supported by thermoplastic polyester elastomer at room temperature, we fabricated a new type of composite PCM (CPCM) that exhibits flexibility even at room temperature. This CPCM demonstrates good shape and thermal stability. Furthermore, the carbon nanotubes-COOH modified with lauric acid (LA) can be uniformly dispersed within the CPCM matrix, thereby enhancing the thermal conductivity of the CPCM. Additionally, the composite material exhibits a promising thermal management performance for high-temperature lithium-ion (Li-ion) batteries. These findings open up new possibilities for the development of room- temperature flexible CPCMs.

相变材料(PCM)能有效解决热能供需不匹配的问题,因此备受关注。然而,PCM 的实际应用仍然受到晶体刚性、易泄漏性和导热性差等固有挑战的阻碍。在这项研究中,我们以相变存储提供的热控制和热塑性聚酯弹性体在室温下支持的弹性行为为基础,制造了一种新型复合 PCM(CPCM),它在室温下也能表现出柔性。这种 CPCM 具有良好的形状和热稳定性。此外,用月桂酸(LA)改性的碳纳米管-COOH 可以均匀地分散在 CPCM 基体中,从而增强了 CPCM 的导热性。此外,这种复合材料在高温锂离子(Li-ion)电池的热管理方面表现出良好的性能。这些发现为室温柔性 CPCM 的开发提供了新的可能性。


Lightweight, freestanding hybrids of graphene and hexagonal boron nitride foams

Patrick Ryan Galligan, Hongwei Liu, Guang Wang, Mohsen Tamtaji, Yaxuan Li, Tsz Wing Tang, Yanguang Zhou, Zhengtang Luo

doi:10.1016/j.compositesa.2024.108176

 

石墨烯和六方氮化硼泡沫的轻质独立混合体

Lightweight boron carbon nitride foams which are a hybrid of graphene and hexagonal boron nitride(hBN), are produced using the nickel template method and remain freestanding after the etching of nickel without the stabilization of a polymer during etching. Chemical vapor deposition (CVD) precursors with varying carbon content were utilized, but only a 10% range of carbon atomic percentage variation is observed in the resulting boron carbon nitride foams due to the high carbon solubility of nickel. However, the cooling rate during the CVD process has a much more significant effect on the carbon content. Moreover, a 6.5-fold increase in resistivity is observed for our foams compared to a graphene foam with an overall trend of decreasing resistance with increasing carbon content. Furthermore, when the foam is infiltrated with epoxy to form a composite at 0.3% volumetric percentage concentration, there is a 27% increase in the thermal conductivity over hBN foam composites. These foams are suitable to use as a substitute for graphene foams when a lower electrical conductivity is desired and could potentially be used as a thermal interface material if a higher pore density nickel template is utilized.

轻质氮化硼碳泡沫是石墨烯和六方氮化硼(hBN)的混合体,采用镍模板法生产,镍蚀刻后仍保持独立,蚀刻过程中无需聚合物稳定。虽然使用了不同碳含量的化学气相沉积(CVD)前驱体,但由于镍的高碳溶解度,在生成的氮化硼泡沫中仅观察到 10%的碳原子百分比变化范围。然而,CVD 过程中的冷却速度对碳含量的影响要大得多。此外,与石墨烯泡沫相比,我们的泡沫的电阻率增加了 6.5 倍,总体趋势是电阻率随着碳含量的增加而降低。此外,当泡沫渗入环氧树脂形成体积百分比浓度为 0.3% 的复合材料时,导热系数比 hBN 泡沫复合材料增加了 27%。当需要较低的导电率时,这些泡沫可用作石墨烯泡沫的替代品,如果使用孔隙密度较高的镍模板,则有可能用作热界面材料。


The delamination performance of composite laminates with bionic high toughness regions

Xiao Yang, Guangji Li, Yu Chen, Shichao Niu, Honglie Song, Xianchang Peng, Pucun Bai, Jing Ni, Chun Shao

doi:10.1016/j.compositesa.2024.108172

具有仿生高韧性区域的复合材料层压板的脱层性能

Inspired by the composite structure of soft and hard phases found inbiological materials, this paper prepares the CF/PPS woven composite laminates with bionic high toughness regions to improve the delamination resistance. The optimal bionic high toughness regions can increase the flexural strength by 75% compared to Baseline. These bionic regions improve the delamination resistance via two mechanisms. i) The paths of crack change from interlaminar to intralaminar because of crack deflection, branching, and convergence. ii) The singular concentrations of interlaminar stress are improved by producing tiny cracks. Finally, the damage mode is investigated in details. It shows that the pure mode II failure is transformed into a mixture of mode I and mode II failures. The cracks are more likely to transition from interlaminar to intralaminar when the distribution of bionic regions is more dispersed. As a result of these regions, the catastrophic delamination failure is improved effectively.

受生物材料中软硬相复合结构的启发,本文制备了具有仿生高韧性区域的 CF/PPS 编织复合材料层压板,以提高抗分层能力。与基线相比,最佳仿生高韧性区域可将抗弯强度提高 75%。i) 由于裂纹偏转、分支和汇聚,裂纹路径从层间变为层内。 ii) 通过产生微小裂纹,改善了层间应力的奇异集中。最后,对破坏模式进行了详细研究。结果表明,纯模式 II 破坏转变为模式 I 和模式 II 的混合破坏。当仿生区域分布更分散时,裂纹更有可能从层间过渡到层内。由于这些区域的存在,灾难性分层破坏得到了有效改善。


Impact behaviour of 3D printed fiber reinforced cementitious composite beams

Jinlong Pan, Pengxin Ping, Boyin Ding, Binrong Zhu, Yuanzheng Lin, Neven Ukrainczyk, Hong Zhang, Jingming Cai

doi:10.1016/j.compositesa.2024.108175

三维打印纤维增强水泥基复合梁的冲击性能

Recent interest has grown in using 3D printing for military and civil defense engineering, particularly for infrastructure resilience against impacts. This study delves into the impact resistance of 3D printed fiber-reinforced cementitious composite (FRCC) beams. By analyzing varying fiber content, impact directions, and 3D printing nozzle sizes, the research found that the total energy dissipation of 3D printed FRCC beams was more than 40% higher and the 3D printed beams exhibited superior impact resistance compared to traditional beams, largely due to the fibers' role. The impact energy dissipation varied with different impact directions for the specimens, and the Z direction was identified as the most resistant, demonstrating anisotropic behavior in impact resistance. Smaller nozzle sizes in printing showed higher total energy dissipation, indicating increased impact resistance. X-ray analysis further revealed that the 3D printing process creates denser beams with better fiber–matrix adhesion and less porosity, improving overall impact resistance.

最近,人们对将三维打印技术用于军事和民防工程,特别是用于基础设施的抗冲击能力越来越感兴趣。本研究深入探讨了三维打印纤维增强水泥基复合材料(FRCC)梁的抗冲击性。通过分析不同的纤维含量、冲击方向和三维打印喷嘴尺寸,研究发现三维打印纤维增强水泥基复合材料梁的总能量耗散比传统梁高 40% 以上,三维打印梁表现出更优越的抗冲击性能,这主要归功于纤维的作用。冲击能量耗散随试样的不同冲击方向而变化,Z 方向的抗冲击能力最强,这表明了抗冲击能力的各向异性。打印中喷嘴尺寸越小,总能量耗散越大,表明抗冲击性越强。X 射线分析进一步表明,三维打印工艺能产生密度更大的梁,纤维与基质的粘附性更好,孔隙率更低,从而提高了整体抗冲击性。


The use of crude carbon dots as green, low-cost and multifunctional additives to improve the curing, mechanical, antioxidative and fluorescence properties of epoxy natural rubber/silica composites

Chaoying Sun, Liwei Li, Haijun Ji, Hui Yang, Guangzhi Jin, Can Jiang, Pingyun Guo, Liqun Zhang, Peng Yu, Runguo Wang

doi:10.1016/j.compositesa.2024.108177

 

使用粗碳点作为绿色、低成本和多功能添加剂,改善环氧天然橡胶/二氧化硅复合材料的固化、机械、抗氧化和荧光特性

Rubbers are acknowledged as strategically important and irreplaceable materials in daily life, and rubber additives are indispensable components for the practical application of the rubber vulcanizate. Developing novel rubber additives is highly desirable, and pursuing multifunctional rubber additives has been one of the major tasks in the field of rubber. Herein, the crude carbon dots (CCDs) without any purification were used as rubber additives for epoxy natural rubber/silica system by conventional milling process. Our results revealed that the CCDs have outstanding advantages, they could not only endow the rubber with charming fluorescence and excellent anti-aging capability, but also improve the curing rate and mechanical performance of rubber composite. Moreover, with the incorporation of CCDs, the rolling resistance of the rubber composite could be remarkably reduced, which is promising for the application of green tyres. Overall, this work convincingly provides novel inspiration to develop novel low-cost yet multifunctional additives for rubber.

橡胶是公认的具有重要战略意义且在日常生活中不可替代的材料,而橡胶添加剂则是橡胶硫化剂实际应用中不可或缺的成分。开发新型橡胶添加剂是非常有必要的,而追求橡胶添加剂的多功能性一直是橡胶领域的主要任务之一。本文采用传统研磨工艺,将未经任何提纯的粗碳点(CCD)用作环氧天然橡胶/二氧化硅体系的橡胶添加剂。结果表明,CCDs 具有突出的优点,不仅能赋予橡胶迷人的荧光和优异的抗老化能力,还能提高橡胶复合材料的硫化速度和机械性能。此外,CCD 的加入还能显著降低橡胶复合材料的滚动阻力,为绿色轮胎的应用带来了希望。总之,这项研究为开发新型低成本多功能橡胶添加剂提供了新的灵感。


Composites Part B: Engineering

A 3D voxel-based mesostructure generator for finite element modelling of tow-based discontinuous composites

Luis Gulfo, Olle Haglund Nilsson, Jacob Sjöberg, Ioannis Katsivalis, Leif E. Asp, Martin Fagerström

doi:10.1016/j.compositesb.2024.111405

基于三维体素的网格结构生成器,用于对拖缆式非连续复合材料进行有限元建模

Tow-based discontinuous composites manufactured with ultra-thin tapes display high stiffness, strength, and in-plane isotropy, thus competing with composite laminates. Their complex 3D microstructure affects the mechanical response, in turn demanding 3D generators that capture the tape waviness, resin pockets, and thickness and fibre content variations. The present work proposes an automated numerical framework combining a 3D voxel-based mesostructure generator with finite element models. A modified 3D random sequential absorption technique is developed with bin-guided allocation, draping, and thickness control. A statistical study is used to size the statistical volume elements and predict the elastic properties of thick, thin, and ultra-thin tow-based discontinuous composites. The results are compared with the experimental values from the literature. Despite uncertainties in physical tape properties, the resulting stiffnesses are predicted with good accuracy.

用超薄带制造的纤网基非连续复合材料具有很高的刚度、强度和面内各向同性,因此可与复合材料层压板相媲美。其复杂的三维微观结构会影响机械响应,因此需要三维生成器来捕捉带状波纹、树脂袋以及厚度和纤维含量的变化。本研究提出了一种自动数值框架,将基于三维体素的中观结构生成器与有限元模型相结合。开发了一种改进的三维随机顺序吸收技术,该技术具有仓引导分配、悬垂和厚度控制功能。统计研究用于确定统计体积元素的大小,并预测厚、薄和超薄丝束基非连续复合材料的弹性特性。研究结果与文献中的实验值进行了比较。尽管物理丝带特性存在不确定性,但所得到的刚度预测准确度很高。


Composites Science and Technology

Green synthesis of positive electrodes for high performance structural batteries - A study on graphene additives

Zhenyuan Xia, Zhaoyang Li, Johanna Xu, Sankar Sasidharan, Jaime S. Sanchez, Vincenzo Palermo, Leif E. Asp

doi:10.1016/j.compscitech.2024.110568

 

高性能结构电池正极的绿色合成--关于石墨烯添加剂的研究

Carbon fibres (CF) have the potential to serve as versatile and multifunctional conductive electrodes within the concept of “structural batteries”. These batteries possess the unique ability to both store electrical energy and bear mechanical loads without requiring extra current collectors. However, numerous challenges remain on the path to commercializing structural batteries. One significant challenge lies in the fabrication process of CF-based cathode composites, including the poor adhesion of active materials to the CF surface and the use of hazardous organic solvents, such as N-methyl pyrrolidone (NMP) through traditional blade coating. In this study, we present a sustainable fabrication approach, using electrophoretic deposition (EPD) to construct positive electrode composites with lithium iron phosphate (LiFePO4) and graphene nanosheets. Especially, ethanol was used as a green solvent replacing NMP to minimize the environmental impact. Meanwhile, the influence of different types of graphene additives (three kinds of graphene nanoplatelets (GNP), four kinds of reduced graphene oxide (rGO) and one home-made graphene) to the relative battery performance were evaluated under a systematic comparative analysis. Among the tested graphene additives, LFP/rGO2 based positive electrode exhibits a desirable specific capacity of 126.2 mAhg−1, maintaining over 93% retention even under the demanding conditions of 2C over 500 cycles.

在 "结构电池 "概念中,碳纤维(CF)具有作为多功能导电电极的潜力。这些电池具有独特的能力,既能储存电能,又能承受机械负载,而无需额外的电流收集器。然而,在实现结构电池商业化的道路上仍存在诸多挑战。其中一个重大挑战在于基于 CF 的阴极复合材料的制造工艺,包括活性材料与 CF 表面的粘附性差,以及通过传统的叶片涂层使用 N-甲基吡咯烷酮(NMP)等有害有机溶剂。在本研究中,我们提出了一种可持续的制造方法,即使用电泳沉积(EPD)来构建磷酸铁锂(LiFePO4)和石墨烯纳米片的正极复合材料。特别是使用乙醇作为绿色溶剂替代 NMP,以最大限度地减少对环境的影响。同时,通过系统比较分析,评估了不同类型的石墨烯添加剂(三种石墨烯纳米片(GNP)、四种还原氧化石墨烯(rGO)和一种自制石墨烯)对相对电池性能的影响。在测试的石墨烯添加剂中,基于 LFP/rGO2 的正极表现出 126.2 mAhg-1 的理想比容量,即使在 500 次以上的 2C 苛刻条件下也能保持 93% 以上的保持率。


Anisotropic elastoplasticity and fracture of SCFR-PEEK composites in complex biaxial loading: Experiments and modelling

Wencheng Liu, Jinlong Liu, Xinghao Li, Jia Huang, Yang Chen, Yulong Li, Jun Ma, Hao Cui

doi:10.1016/j.compscitech.2024.110569

 

复杂双轴加载条件下 SCFR-PEEK 复合材料的各向异性弹塑性和断裂:实验与建模

This research aims to gain insight into the anisotropic deformation and fracture behaviours of short carbon fibre reinforced polyether-ether ketone composites (SCFR-PEEK) under complex loading using experimental and modelling approaches. Novel biaxial tensile experiments using optimised cruciform specimens are designed and performed to study the anisotropic elastoplasticity and fracture behaviours of SCFR-PEEK in various stress states. An advanced anisotropic constitutive model was developed, experimentally calibrated, numerically implemented, and successfully verified by mechanical responses of biaxial tension with various stress ratios. Furthermore, using a hybrid experimental-numerical approach, the biaxial failure stress at crack initiation sites captured by a high-speed camera in biaxial tension was obtained. Employing experimental failure stresses at various uniaxial and biaxial stress states, a maximum stress based failure criterion was developed, which is coupled with the anisotropic elastoplastic model, thus enabling the description the anisotropic elastoplastic and failure behaviours under complex loading. The prediction of the failure of SCFR-PEEK in complex biaxial stress states using the coupled model is in good agreement with biaxial tensile experimental results using circular-notched specimens. Therefore, the developed model is verified to be capable of describing both elastoplastic deformation and fracture failure behaviours of SCFR-PEEK composites in complex loading.

本研究旨在利用实验和建模方法深入了解短碳纤维增强聚醚醚酮复合材料(SCFR-PEEK)在复杂载荷下的各向异性变形和断裂行为。利用优化的十字形试样设计并进行了新型双轴拉伸实验,以研究 SCFR-PEEK 在各种应力状态下的各向异性弹塑性和断裂行为。开发了一种先进的各向异性构成模型,对其进行了实验校准和数值计算,并通过各种应力比的双轴拉伸机械响应进行了成功验证。此外,利用实验-数值混合方法,获得了高速摄像机捕捉到的双轴拉伸下裂纹起始点的双轴破坏应力。利用各种单轴和双轴应力状态下的实验破坏应力,制定了基于最大应力的破坏准则,该准则与各向异性弹塑性模型相结合,从而能够描述复杂加载下的各向异性弹塑性和破坏行为。使用耦合模型对 SCFR-PEEK 在复杂双轴应力状态下的破坏进行的预测与使用圆形缺口试样进行的双轴拉伸实验结果非常吻合。因此,验证了所开发的模型能够描述复杂加载下 SCFR-PEEK 复合材料的弹塑性变形和断裂失效行为。


Balancing creep resistance and resilience in composites: Leveraging multidirectional and hierarchical structure of collagen fibres

Chao Lei, Weixing Xu, Yunhang Zeng, Jibo Zhou, Bi Shi

doi:10.1016/j.compscitech.2024.110570

 

平衡复合材料的抗蠕变性和回弹性:利用胶原纤维的多向和分层结构

Conventional methods of enhancing the creep resistance of polyvinyl chloride (PVC) often compromise its resilience. This study proposes a novel strategy to achieve a balance between creep resistance and resilience in PVC-matrix composites by incorporating epoxidised soybean oil-modified collagen fibres (MCFs). A comparative analysis of creep and recovery behaviour was conducted among MCF/PVC, pure PVC, and other conventional modified systems. Results revealed that MCF/PVC exhibited a lower total creep strain (12.82%) than pure PVC and a higher recoverable deformation (10.80%) than the other conventional modified systems. Moreover, MCF/PVC had the longest predicted creep lifetime among all the modification systems, which was 103 times longer than that of pure PVC. These improvements were attributed to the natural multidirectional and hierarchical structure of MCF, which hindered the movement of PVC chains and provided sufficient gaps for recoverable deformation. This work provides a new perspective on developing resilient creep-resistant modifications of polymers by leveraging the structural advantages of natural products.

增强聚氯乙烯(PVC)抗蠕变性的传统方法往往会损害其回弹性。本研究提出了一种新策略,通过加入环氧化大豆油改性胶原纤维(MCF),在 PVC 基质复合材料中实现抗蠕变性和回弹性之间的平衡。对 MCF/PVC、纯 PVC 和其他传统改性体系的蠕变和恢复行为进行了比较分析。结果显示,MCF/PVC 的总蠕变应变(12.82%)低于纯 PVC,而可恢复变形(10.80%)则高于其他传统改性体系。此外,在所有改性体系中,MCF/PVC 的预测蠕变寿命最长,是纯 PVC 的 103 倍。这些改进归功于 MCF 的天然多向分层结构,它阻碍了聚氯乙烯链的运动,并为可恢复变形提供了足够的间隙。这项研究为利用天然产品的结构优势开发弹性抗蠕变改性聚合物提供了新的视角。


Synergistic interactions of citric acid grafted β-cyclodextrin and polyethyleneimine for improving interfacial properties of basalt fiber/epoxy composites

Qing Wu, Renjie Yao, Hao Deng, Bolin Xiao, Ziyi Ye, Yating Li, Jianfeng Zhu

doi:10.1016/j.compscitech.2024.110575

 

柠檬酸接枝β-环糊精和聚乙烯亚胺的协同作用改善玄武岩纤维/环氧树脂复合材料的界面性能

Basalt fiber responds well to the global concept of environmental protection due to its attractive superiorities of green and excellent mechanical performance. However, the ultra-low interfacial adhesion strength of fiber-to-matrix deeply restricts its wide application. Moreover, attempts to utilize natural- or bio-materials on basalt fiber towards growth in interfacial adhesion remains in its infancy, if feasible, it would make green materials shine brilliantly. Herein, we install citric acid modified β-cyclodextrin (β-CD) and polyethyleneimine (PEI) on basalt fiber via dipping approach for the first time, which results in 76.9% increment in fiber-to-epoxy adhesion over control fiber. Unique inner hydrophobic and outer hydrophilic conical cavity architecture of β-CD endows interphase with dense ring hydrogen bond band “core”- covalent/ionic bonding “shell” multiple interactions that balance stress transfer and energy dissipation. Additionally, “rigid” β-CD and “flexible” PEI function as crack deflection and stress distribution for gaining stronger interphase of basalt fiber composites. This paper serves to provide a new exploitation for advancing green and high-performance composites.

玄武岩纤维因其绿色环保和优异的机械性能而深受全球环保理念的青睐。然而,纤维与基体之间超低的界面粘附强度深深限制了它的广泛应用。此外,在玄武岩纤维上利用天然或生物材料提高界面粘附力的尝试仍处于起步阶段,如果可行,将使绿色材料大放异彩。在本文中,我们首次通过浸渍法在玄武岩纤维上安装了柠檬酸改性的β-环糊精(β-CD)和聚乙烯亚胺(PEI),与对照纤维相比,纤维与环氧树脂的粘附力提高了 76.9%。β-CD独特的内疏水、外亲水的锥形空腔结构,使相间具有致密的环状氢键带 "核"-共价/离子键 "壳 "多重相互作用,从而平衡了应力传递和能量耗散。此外,"刚性 "β-CD 和 "柔性 "PEI 还能起到裂纹偏转和应力分布的作用,从而增强玄武岩纤维复合材料相间的强度。本文为推动绿色高性能复合材料的发展提供了新的思路。


Hybrid cross-linking for the synthesis of highly tough fluorescent alginate fibers

Dongnan Zhang, Hong Zhang, Song Tang, Zijian Bai, Jianyu Jiang, Yao Wang, Yue Yu, Fengyu Quan

doi:10.1016/j.compscitech.2024.110577

 

用于合成高韧性荧光藻酸盐纤维的混合交联技术

The limited mechanical performance and functional constraints of alginate fibers significantly impede their development in the context of professional research. To address the aforementioned issues, this study initially utilized polyethyleneimine (PEI) and citric acid to synthesize carbon quantum dots (CD) with surface amino functionalization. Subsequently, in a sodium alginate (SA) solution, CD and vinyl silicon-based nanoparticles (VSNP) were co-introduced. Utilizing the abundant hydroxyl and carboxyl groups in polysaccharides, stable interactions were achieved with CD and VSNP. Incorporating a dynamic hydrogen-bonded crosslinking network among CD, VSNP and SA, the establishment of a calcium alginate (CA) ionically crosslinked network is facilitated via calcium-sodium ion exchange. Additionally, the interwoven and interlocked structure between the aforementioned dual networks was established. Employing a wet spinning process, the synergistic multiple dynamic energy dissipation mechanisms significantly enhance the mechanical performance. Fluorescent alginate fibers (CA/VSNP/CD) were prepared. The tensile strength was 3.81 cN/dtex, and the elongation at break was 13.16%. Compared to pure CA fibers, there were respective increases of 95.38% and 82.02%. Simultaneously, the fibers exhibit excitation-dependent emission characteristics. This work lays the foundation for potential applications of fluorescent alginate fibers in environmental monitoring, chemical sensors, dynamic anti-counterfeiting, and biomedical fields.

海藻酸纤维有限的机械性能和功能限制极大地阻碍了其在专业研究领域的发展。针对上述问题,本研究首先利用聚乙烯亚胺(PEI)和柠檬酸合成了表面氨基官能化的碳量子点(CD)。随后,在海藻酸钠(SA)溶液中,CD 和乙烯基硅基纳米粒子(VSNP)被共同引入。利用多糖中丰富的羟基和羧基,CD 和 VSNP 实现了稳定的相互作用。在 CD、VSNP 和 SA 之间加入动态氢键交联网络,通过钙钠离子交换促进藻酸钙(CA)离子交联网络的建立。此外,还建立了上述双网络之间的交织和互锁结构。采用湿法纺丝工艺,协同多重动态消能机制显著提高了机械性能。制备出了荧光藻酸盐纤维(CA/VSNP/CD)。拉伸强度为 3.81 cN/dtex,断裂伸长率为 13.16%。与纯 CA 纤维相比,分别提高了 95.38% 和 82.02%。同时,这种纤维还表现出与激发相关的发射特性。这项工作为荧光藻酸盐纤维在环境监测、化学传感器、动态防伪和生物医学领域的潜在应用奠定了基础。


Liquid metal-modified boron nitride for polytetrafluoroethylene composites with enhanced thermal conductivity and peel strength

Rui Xue, Zilong Xie, Songgang Chai, Tianhao Yang, Rui Feng, Lu He, Kai Wu, Qin Zhang, Qiang Fu

doi:10.1016/j.compscitech.2024.110572

 

用于聚四氟乙烯复合材料的液态金属改性氮化硼,可增强导热性和剥离强度

Polytetrafluoroethylene (PTFE)/boron nitride (BN) composites has ultra-low dielectric loss and thermal conductivity, making it a suitable choice for high-frequency communication copper-clad laminate. However, the low peel strengthens of these composites restricted the further application, due to the low polarity and smooth surface of BN. Here, we assemble liquid metal (LM) on BN filler (LM-BN) via a mechanochemistry method. The surface polarity and roughness of BN can be enhanced by the oxidized layer from LM. The thermal interfacial overlap between BN sheets can be enhanced by LM droplets. Consequently, at filler content of 50 vol%, the thermal conductivity increases from 0.3 W/m⋅K of PTFE to 1.90 W/m⋅K for PTFE/BN composites, to 2.05 W/m⋅K for PTFE/LM-BN composites, and the peel strength exhibit a nearly 100% increment from 0.19 of PTFE/BN to 0.39 N/mm of PTFE/LM-BN. Along with low dielectric loss, excellent thermal conductivity, peel strength, and reduced thermal expansion, this method ensures a wider application of PTFE/LM-BN composites in electronic packaging.

聚四氟乙烯(PTFE)/氮化硼(BN)复合材料具有超低的介电损耗和热导率,是高频通信铜箔层压板的理想选择。然而,由于 BN 的极性低且表面光滑,这些复合材料的剥离强度低,限制了其进一步应用。在此,我们通过机械化学方法在 BN 填料上组装液态金属(LM)(LM-BN)。液态金属氧化层可增强 BN 的表面极性和粗糙度。LM 液滴可增强 BN 片材之间的热界面重叠。因此,当填料含量为 50 Vol% 时,导热系数从 PTFE 的 0.3 W/m⋅K 增加到 PTFE/BN 复合材料的 1.90 W/m⋅K,再到 PTFE/LM-BN 复合材料的 2.05 W/m⋅K,剥离强度从 PTFE/BN 的 0.19 增加到 PTFE/LM-BN 的 0.39 N/mm,增幅接近 100%。该方法具有低介电损耗、优异的导热性、剥离强度和较低的热膨胀率,可确保 PTFE/LM-BN 复合材料在电子封装中得到更广泛的应用。



来源:复合材料力学仿真Composites FEM
ACTMechanicalAdditiveSystemInspire断裂复合材料化学电路电子通信裂纹材料多尺度仿生创新方法控制
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【新文速递】2024年3月30日复合材料SCI期刊最新文章

今日更新:Composite Structures 6 篇,Composites Part A: Applied Science and Manufacturing 1 篇,Composites Part B: Engineering 1 篇,Composites Science and Technology 2 篇Composite StructuresNonlinear stochastic behavior of soft-core sandwich panelsN. Malkiel, O. Rabinovitchdoi:10.1016/j.compstruct.2024.118085软芯夹芯板的非线性随机行为The nonlinear stochastic behavior of soft-core sandwich panels and the evolution of uncertainty along the nonlinear path are investigated. The paper focuses on the way the geometrically nonlinear and unstable behavior is affected by uncertainty and considers, for the first time, the evolution of uncertainty along the unstable structural response. The structural modeling relies on the EHSAPT and its integration into the geometrically nonlinear stochastic regime. A tailored nonlinear FE model that is based on a variational formulation and an arc-length solution scheme are developed. The stochastic analysis adopts the Perturbation-based SFEM and its generalization for the evolution of uncertainty along the process axis. A numerical study demonstrates the stochastic methodology and explores the impact of uncertainty on the nonlinear structural behavior. The evolution of the stochastic stress resultants at the displaced end is studied along the two axes of evolution. The differences between the two representations and their physical and engineering significance are highlighted revealing significant changes to the uncertainty evolution pattern with the shift from global buckling to localized wrinkling instabilities. The representation of the stochastic results along the process axis also quantifies the level of uncertainty near critical and singular points where conventional analyses diverge.本文研究了软芯夹芯板的非线性随机行为以及不确定性沿非线性路径的演变。论文重点研究了几何非线性和不稳定行为受不确定性影响的方式,并首次考虑了不确定性沿不稳定结构响应的演变。结构建模依赖于 EHSAPT 及其与几何非线性随机机制的整合。基于变分公式和弧长求解方案,开发了一个量身定制的非线性 FE 模型。随机分析采用了基于扰动的 SFEM 及其广义方法,用于分析不确定性沿过程轴的演变。数值研究展示了随机方法,并探讨了不确定性对非线性结构行为的影响。沿两个演化轴研究了位移端随机应力结果的演化。研究强调了两种表示方法之间的差异及其物理和工程意义,揭示了不确定性演变模式从整体屈曲向局部起皱不稳定性转变过程中的显著变化。沿过程轴的随机结果表示法还量化了临界点和奇异点附近的不确定性水平,在这些地方,传统的分析会出现偏差。Introducing a novel piezoelectric-based tunable design for mode-localized mass micro-sensorsHossein Ali Alam-Hakkakan, Amir Reza Askari, Masoud Tahanidoi:10.1016/j.compstruct.2024.118086为模式定位质量微型传感器引入基于压电的新型可调设计This investigation focuses on developing a new sensitivity-improving approach for high-order mode-localized mass micro-sensors by utilizing the capabilities of piezoelectric materials. To this end, an electrostatically coupled micro-beam as the building block of MEMS mass sensors is considered. The present design includes the incorporation of a patterned arrangement of piezoelectric thin films placed on the lower electrode of the system. The nonlinear reduced equations of motion for the introduced tunable system are derived by employing the Hamilton principle in conjunction with the Euler-Bernoulli beam theory and the Ritz discretization procedure. These equations are subsequently solved using the harmonic balance method. The present findings are validated by those available in the literature for the case of static excitation. In addition, the eigenvalue loci of the proposed system have been compared and verified by those obtained through three-dimensional finite element simulations carried out in COMSOL Multiphysics commercial software. Taking the shift of the amplitude ratio as the measure demonstrating the sensitivity of the proposed design, it is observed that incorporating piezoelectric excitation can significantly enhance the efficiency of these systems more than two times in comparison to conventional mode-localized mass micro-sensors without piezoelectric layers.本研究的重点是利用压电材料的功能,为高阶模式定位质量微传感器开发一种新的灵敏度改进方法。为此,我们考虑采用静电耦合微梁作为 MEMS 质量传感器的构件。本设计包括将压电薄膜图案化布置在系统的下电极上。通过结合使用汉密尔顿原理、欧拉-伯努利梁理论和里兹离散化程序,得出了引入的可调系统的非线性还原运动方程。这些方程随后用谐波平衡法求解。目前的研究结果与文献中关于静态激励情况的研究结果相吻合。此外,通过 COMSOL Multiphysics 商业软件进行的三维有限元模拟得到的特征值位置也与所提出系统的特征值位置进行了比较和验证。以振幅比的偏移量来衡量拟议设计的灵敏度,可以发现,与不带压电层的传统模式定位质量微传感器相比,加入压电激励可显著提高这些系统的效率两倍以上。WrapToR shells: Concept introduction, experimental testing, and design space explorationChris F. Grace, Mark Schenk, Benjamin K.S. Woodsdoi:10.1016/j.compstruct.2024.118089WrapToR 外壳:概念介绍、实验测试和设计空间探索This work introduces a novel truss stiffener concept for lightweight structural panels as an alternative to sandwich panels or stringer stiffened panels. The Wrapped Tow Reinforced (WrapToR) truss concept is modified to create stiffened composite panel structures (referred to here as WrapToR Shells). A prototype WrapToR Shell unit cell is manufactured and tested under three-point bending, where it demonstrates high levels of specific stiffness and strength. This experimental result is benchmarked against idealised sandwich panels via a low fidelity comparative analysis, and the study shows that even a best-case sandwich panel of equivalent mass under a representative bending load has an 83% increase in displacement, highlighting the excellent stiffness truss reinforced panels can provide. The design space available to the truss reinforced panels is then explored using finite element analysis and a simple parameter sweep of key truss design variables. A Pareto frontier between the competing objectives of minimising mass and maximising rigidity is shown, and global trends in performance are highlighted. It is observed that increasing the size of the truss profile or longitudinal member has a near linear increase on EI/mass, whereas for increasing shear member angle the inverse is true. For increasing shear member diameter, a less obvious effect on EI/mass is seen, indicating a more complex relationship with the other design variables.这项研究为轻质结构板材引入了一种新颖的桁架加劲概念,以替代夹芯板或钢绞线加劲板。对缠绕缆索加固(WrapToR)桁架概念进行了修改,以创建加劲复合板结构(此处称为 WrapToR Shells)。WrapToR Shell 单元尺寸原型已制造完成,并在三点弯曲下进行了测试,显示出较高的特定刚度和强度。实验结果通过低保真对比分析与理想的夹层板进行了比较,研究表明,即使是同等质量的最佳夹层板,在代表性弯曲载荷下的位移也增加了 83%,这凸显了桁架加固板可提供的出色刚度。然后,利用有限元分析和关键桁架设计变量的简单参数扫描,探索了桁架加固板的设计空间。显示了质量最小化和刚度最大化这两个相互竞争的目标之间的帕累托前沿,并强调了性能方面的全球趋势。据观察,增加桁架轮廓或纵向构件的尺寸对 EI/质量有近乎线性的增加,而增加剪力构件角度则相反。增加剪力构件直径对 EI/质量的影响并不明显,这表明与其他设计变量的关系更为复杂。Passively morphing trailing edge design for composite tidal turbine bladesJames.M. Maguire, Dimitrios Mamalis, Shūji Ōtomo, Edward D. McCarthydoi:10.1016/j.compstruct.2024.118090复合材料潮汐涡轮机叶片的被动变形后缘设计Numerical simulations and lab-scale experiments are used to evaluate three passively morphing trailing edge designs for a composite tidal turbine blade. The designs include a closed trailing edge, an open trailing edge, and a corrugated trailing edge. It is shown that geometric stiffness, as well as material stiffness, play key roles in achieving the desired deformation of the trailing edge. One trailing edge design is down-selected for further investigation via full-scale numerical simulations. These simulations demonstrate how the composite lay-up influences the morphing response of the trailing edge and its likelihood of material failure. The influence of camber is also investigated in terms of both material behaviour and hydrodynamic performance. Finally, the potential for bend-twist coupling of the laminate skins is explored.通过数值模拟和实验室规模的实验,对复合材料潮汐涡轮叶片的三种被动变形后缘设计进行了评估。这些设计包括封闭式后缘、开放式后缘和波纹式后缘。结果表明,几何刚度和材料刚度在实现所需的后缘变形中起着关键作用。通过全尺寸数值模拟,最终选择了一种后缘设计进行进一步研究。模拟结果表明了复合材料铺层如何影响后缘的变形响应及其材料失效的可能性。此外,还研究了外倾角对材料性能和流体力学性能的影响。最后,还探讨了层压蒙皮弯曲-扭转耦合的可能性。Micromechanical modeling for longitudinal tensile property of unidirectional CFRP considering dispersion of fiber propertiesHao Wang, Xiang-Yu Zhong, He Jia, Lian-Wang Zhang, Han-Song Liu, Ming-Chen Sun, Tian-Wei Liu, Jiang-Bo Bai, Si-Cheng Ge, Jian-Wen Baodoi:10.1016/j.compstruct.2024.118081考虑纤维分散特性的单向 CFRP 纵向拉伸性能微观力学模型Longitudinal tensile failure prediction has always been the focus of research on unidirectional (UD) Carbon Fiber Reinforced Polymer (CFRP). In this paper, the longitudinal tensile tests of unidirectional T800 grade carbon fiber reinforced epoxy resin composite were carried out first. The experimental stress–strain curves show that there are obvious progressive damages before the final failures of the specimens. However, this phenomenon is usually neglected in most of the existing investigations and tests to only obtain elastic modulus and ultimate strength. Thus, a Representative Volume Element (RVE) model based on micromechanics was established using finite element method, considering the randomness of fiber spatial distribution and fiber strength. The tensile strength of fiber monofilaments was assumed to follow a statistical two-parameter Weibull distribution. The failure process of UD composite under longitudinal tensile load was simulated by explicit finite element method. The stress–strain curves obtained by simulation are in good agreement with the experimental results. Finally, the influence of different boundary conditions on the calculation of the RVE was studied. It is found that the final failure strengths of the RVE with uniform displacement boundary conditions are similar to the case of periodic boundary conditions, while the former has higher computational efficiency.纵向拉伸失效预测一直是单向(UD)碳纤维增强聚合物(CFRP)的研究重点。本文首先对单向 T800 级碳纤维增强环氧树脂复合材料进行了纵向拉伸试验。实验应力-应变曲线显示,试样在最终失效前存在明显的渐进式损伤。然而,在现有的大多数研究和测试中,这种现象通常被忽略,而只获得弹性模量和极限强度。因此,考虑到纤维空间分布和纤维强度的随机性,采用有限元方法建立了基于微观力学的代表体积元素(RVE)模型。假设纤维单丝的拉伸强度遵循统计上的双参数威布尔分布。采用显式有限元法模拟了 UD 复合材料在纵向拉伸载荷作用下的破坏过程。模拟得到的应力-应变曲线与实验结果十分吻合。最后,研究了不同边界条件对 RVE 计算的影响。结果发现,采用均匀位移边界条件的 RVE 的最终破坏强度与采用周期边界条件的情况相似,而前者的计算效率更高。In-situ failure behavior and interfacial bonding of an interpenetrating metal matrix composite reinforced with lattice-like metallic glass (Ni60Nb20Ta20) preformKerstin Dittmann, Robert Gruhl, Anna Trauth, Kay André Weidenmanndoi:10.1016/j.compstruct.2024.118084用晶格状金属玻璃(Ni60Nb20Ta20)预制件增强的互穿金属基复合材料的原位破坏行为和界面粘接性Metallic glasses (MG) have an amorphous atomic structure and exhibit several exceptional properties such as high strength, hardness associated with high elastic strain limit and elastic energy storage. But MGs are also prone to brittle fracture, making them difficult to use as monolithic structural components and might better be used as a reinforcement phase in hybrid composites such as metal matrix composites (MMC). The failure behavior of composites depends on the structure of the reinforcement phase. In this work, the failure behavior of an interpenetrating MMC reinforced with a MG (Ni60Nb20Ta20) lattice-like preform and AlSi12-matrix was investigated by in-situ compression tests under scanning electron microscopy to get a better understanding of the influence of the lattice-like preform and mechanical interference between both phases. Additionally, microstructure analysis by scanning transmission electron microscopy and energy dispersive X-ray measurements were carried out to gain insight into the chemical composition of the interfaces. The failure behavior in manufacturing direction of the MMC is dominated by shear stress whereas transversely to manufacturing direction by normal stress and exhibits therefore an anisotropic failure behavior. Investigations of the interfaces show more of a mechanical than chemical bonding but in general a good interfacial bonding was confirmed.金属玻璃(MG)具有非晶态原子结构,表现出多种优异特性,如高强度、与高弹性应变极限相关的硬度和弹性储能。但金属玻璃也容易发生脆性断裂,因此难以用作整体结构组件,最好是用作金属基复合材料(MMC)等混合复合材料的增强相。复合材料的破坏行为取决于增强相的结构。在这项研究中,通过在扫描电子显微镜下进行原位压缩试验,研究了用 MG(Ni60Nb20Ta20)晶格状预成型体和 AlSi12 基质增强的互穿 MMC 的破坏行为,以便更好地了解晶格状预成型体的影响以及两相之间的机械干涉。此外,还通过扫描透射电子显微镜和能量色散 X 射线测量进行了微观结构分析,以深入了解界面的化学成分。MMC 在制造方向上的破坏行为由剪应力主导,而横向破坏行为则由法向应力主导,因此表现出各向异性的破坏行为。对界面的研究表明,机械结合多于化学结合,但总体而言,界面结合良好。Composites Part A: Applied Science and ManufacturingDeformation characterization of multi-morphology composite cellular hyperelastic structure under biaxial tension: Analytic approaches for sensor applicationsYoungdoo Kim, Seung-Hwan Changdoi:10.1016/j.compositesa.2024.108167双轴拉伸下多形态复合蜂窝超弹性结构的变形表征:传感器应用的分析方法As a preliminary study to develop an effective stretchable sensor, we implemented multi-morphology cellular structures in the gauge area of a biaxial tensile specimen to obtain the desired biaxial mechanical behaviour. A numerical parametric study was conducted by considering the unit cell geometries, four biaxial tension conditions, and three groups of unit cells. The parametric study reveals that a multi-morphology composite cellular (M2C2) specimen with compliant unit cells near the centre and stiff unit cells along the border of the gauge area shows high linearity between the force and displacement relationships and high compliance. M2C2 specimens optimised using the Bayesian optimisation process share similar geometric patterns found in the parametric study and show enhancements in linearity and compliance up to 40.4 % and 65.6 %, respectively, compared with those of a conventional solid specimen.作为开发有效可拉伸传感器的初步研究,我们在双轴拉伸试样的量规区域采用了多形态单元结构,以获得所需的双轴机械性能。通过考虑单元格几何形状、四种双轴拉伸条件和三组单元格,进行了数值参数研究。参数研究结果表明,在靠近中心的单元格为顺应性单元格,沿着量规区域边界的单元格为刚性单元格的多形态复合单元格(M2C2)试样显示出力与位移关系的高度线性和高顺应性。使用贝叶斯优化过程优化的 M2C2 试样与参数研究中发现的几何形态相似,与传统的实心试样相比,线性度和顺应性分别提高了 40.4% 和 65.6%。Composites Part B: EngineeringECM-based ca2+/l-arginine/NO periosteum nourishes bone defect microenvironment, directs macrophage polarity, and accelerates osteogenesis and angiogenesisHo-Pan Bei, Xiongfa Ji, Tianpeng Xu, Zhenhua Chen, Chun-Hei Lam, Xintong Zhou, Yuhe Yang, Yu Zhang, Chunyi Wen, Yaxiong Liu, Xin Zhaodoi:10.1016/j.compositesb.2024.111410基于 ECM 的 ca2+/l- 精氨酸/NO 骨膜可滋养骨缺损微环境,引导巨噬细胞极性,加速骨生成和血管生成The natural periosteum is responsible for supporting bone homeostasis and initiating repair, but is often damaged during bone fracture, causing acute inflammation and loss of a functioning substratum for induction of new bone formation. Here, we propose an ECM-based Ca2+/l-arginine/nitric oxide (NO) electrospun periosteum to reinitiate bone regeneration. The multifaceted action of NO could promote osteoblastic differentiation, angiogenesis and polarization of macrophages, while accelerating new bone formation, enhancing bone quality and reducing inflammation in a rat critical size calvarial defect model, acting as a mainspring that drives the rest of the PI3K-AKT pathway including the downstream action of VEGF, MAPK and mTOR signalling. The modulation of NO cycle by periosteum scaffold is envisioned to be highly efficient at supporting bone grafting surgeries, with simple and clean clinical translation and implications for anti-inflammatory healing.天然骨膜负责支持骨平衡和启动修复,但在骨折过程中往往会受到破坏,导致急性炎症,失去诱导新骨形成的功能基质。在这里,我们提出了一种基于 ECM 的 Ca2+/l- 精氨酸/一氧化氮(NO)电纺骨膜来重新启动骨再生。在大鼠临界尺寸腓骨缺损模型中,一氧化氮的多方面作用可促进成骨细胞分化、血管生成和巨噬细胞极化,同时加速新骨形成、提高骨质量并减少炎症,是驱动 PI3K-AKT 通路其余部分(包括 VEGF、MAPK 和 mTOR 信号的下游作用)的主要动力。骨膜支架对氮氧化物循环的调节可高效地支持植骨手术,并可简单明了地应用于临床,对抗炎愈合具有重要意义。Composites Science and TechnologyAchieving super-tough high-density polyethylene with promising foamability using silane crosslinked polyolefin elastomer nanofibrils networkMohamad Kheradmandkeysomi, Amirmehdi Salehi, Amirjalal Jalali, Hamidreza Akrami, Chul B. Parkdoi:10.1016/j.compscitech.2024.110576 利用硅烷交联聚烯烃弹性体纳米纤维网络实现具有良好发泡性能的超强韧性高密度聚乙烯This study presents the in-situ rubber nanofibrillation of high-density polyethylene (HDPE), metallocene based polyolefin elastomer (POE) composites employing spunbond technology. The process commenced with the grafting of vinyl trimethoxy silane (VTMS) onto POE chains, a crucial step to preserve the fibrillar structure. Two distinct peroxide initiators, dicumyl peroxide (DCP) and di(t-butyl) peroxide (DTBP), were employed to initiate the grafting reaction. Results from gel content and melt flow index tests demonstrated that DTBP performed more effectively as an initiator than DCP. The grafted elastomers were then incorporated into the HDPE matrix using spunbonding. Subsequently, the fibrillated POE-g-VTMS were crosslinked using moisture to preserve the morphology. Scanning electron microscopy (SEM) images showed the generation of crosslinked nano-scale size POE-g-VTMS fibers in the range of 50–125 nm. Based on the rheological data, drawn crosslinked POE-g-VTMS phase formed an interconnected network, resulting in a remarkable increase in viscosity and storage modulus at the low-frequency range. Additionally, the stretched samples exhibited noticeable strain-hardening behavior at specific extension rates. Notably, this in-situ fibrillation process significantly enhanced HDPE's foaming ability, evident in decreased cell size and increased cell density. Tensile test results conducted at room temperature and subzero temperature (−40 °C) also suggested a substantial enhancement in the elongation at break of the HDPE nanofibrillated composites compared to the unstretched samples.本研究采用纺粘技术对高密度聚乙烯(HDPE)和茂金属基聚烯烃弹性体(POE)复合材料进行原位橡胶纳米纤化。该工艺首先将乙烯基三甲氧基硅烷(VTMS)接枝到 POE 链上,这是保持纤维结构的关键步骤。接枝反应采用了两种不同的过氧化物引发剂,即过氧化二辛酯(DCP)和过氧化二(叔丁基)酯(DTBP)。凝胶含量和熔体流动指数测试结果表明,DTBP 作为引发剂比 DCP 更有效。接枝的弹性体随后通过纺粘法与高密度聚乙烯基体结合。随后,利用湿气对纤维化的 POE-g-VTMS 进行交联,以保持其形态。扫描电子显微镜(SEM)图像显示,生成的交联纳米级 POE-g-VTMS 纤维的尺寸范围为 50-125 nm。根据流变学数据,拉伸交联的 POE-g-VTMS 相形成了一个相互连接的网络,导致低频范围内的粘度和存储模量显著增加。此外,拉伸样品在特定拉伸速率下表现出明显的应变硬化行为。值得注意的是,这种原位纤化过程显著增强了高密度聚乙烯的发泡能力,表现为细胞尺寸减小,细胞密度增加。在室温和零下温度(-40 °C)下进行的拉伸测试结果也表明,与未拉伸样品相比,高密度聚乙烯纳米纤化复合材料的断裂伸长率大幅提高。Novel approach for optimizing mechanical and damping performance of MABS composites reinforced with basalt fibers: An experimental studyMd Abu Shaid Sujon, Davide Masato, Tito Andriollo, Zhihao Pan, Venkata Karthik Nadimpalli, Vicente Cutanda Henriquez, Aminul Islamdoi:10.1016/j.compscitech.2024.110578 优化用玄武岩纤维增强的 MABS 复合材料的机械和阻尼性能的新方法:实验研究The purpose of this research is to explore how basalt fibers, when compounded in specific proportions, impact the mechanical and damping attributes of methyl methacrylate acrylonitrile butadiene styrene (MABS). The fabrication process involved compounding basalt fibers in a twin-screw extruder at four distinct weight percentages: 5%, 10%, 15%, and 20%, with an MABS matrix. This study uniquely employs a comprehensive suite of characterization techniques—including dynamic mechanical analysis (DMA), thermogravimetric analysis (TGA), X-ray microcomputed tomography (micro-CT), scanning electron microscopy (SEM), tensile tests, and density measurements—to evaluate the composite's performance. The research significantly reveals that the integration of basalt fibers enhances the damping characteristics of MABS composites, as confirmed by DMA. Additionally, micro-CT scans provide unprecedented insights into the uniform distribution of basalt fibers within the MABS matrix, thereby elucidating the underlying mechanisms for the observed improvements. TGA data further bolsters the composite's thermal resilience, revealing its aptitude for high-temperature applications. Our findings establish a novel correlation between the basalt fiber weight percentage and the damping properties, revealing a non-monotonic relationship. This study thus not only augments the understanding of MABS-based composites but also opens new avenues for the exploitation of basalt fibers in advanced composite materials, particularly in terms of their damping capabilities.本研究的目的是探讨玄武岩纤维按特定比例混合后,如何影响甲基丙烯酸甲酯丙烯腈丁二烯苯乙烯(MABS)的机械和阻尼属性。制造过程包括在双螺杆挤出机中以四种不同的重量比例混合玄武岩纤维:5%、10%、15% 和 20% 的比例与 MABS 基质混合。这项研究独特地采用了一整套表征技术,包括动态机械分析 (DMA)、热重分析 (TGA)、X 射线微计算机断层扫描 (micro-CT)、扫描电子显微镜 (SEM)、拉伸试验和密度测定,以评估复合材料的性能。研究结果表明,玄武岩纤维的集成增强了 MABS 复合材料的阻尼特性,这一点已得到 DMA 的证实。此外,显微 CT 扫描为了解玄武岩纤维在 MABS 基体中的均匀分布提供了前所未有的视角,从而阐明了所观察到的改进的内在机制。TGA 数据进一步增强了复合材料的热弹性,揭示了其在高温应用中的适用性。我们的研究结果在玄武岩纤维重量百分比和阻尼特性之间建立了一种新的相关性,揭示了一种非单调关系。因此,这项研究不仅加深了人们对基于 MABS 的复合材料的了解,还为在先进复合材料中利用玄武岩纤维开辟了新的途径,尤其是在阻尼能力方面。来源:复合材料力学仿真Composites FEM

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