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【新文速递】2024年12月10日复合材料SCI期刊最新文章

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今日更新:Composite Structures 3 篇,Composites Part A: Applied Science and Manufacturing 2 篇,Composites Part B: Engineering 2 篇,Composites Science and Technology 1 篇

Composite Structures

Rapid identification of fatigue degradation law of composite material based on IR thermography

Yan Yan, Marie-Laetitia Pastor, Emmanuelle Abisset-Chavanne, Xiaojing Gong

doi:10.1016/j.compstruct.2024.118787

基于红外热像仪的复合材料疲劳退化规律快速识别

The stiffness degradation law is a key part of the simulation model to predict the fatigue behaviors of CFRPs. Traditional approaches to determine this law are time-consuming while with infrared radiation (IR) thermography, the stiffness degradation can be characterized by applying a rapid fatigue test, which takes a fairly short period. However, the stiffness degradation measured during rapid fatigue tests by thermography is under multiple stress levels and limited cycles. In this work, a stiffness degradation law determined by classic fatigue test, originally proposed for unidirectional CFRP laminates, has been extended to multi-directional laminates. Then, a strategy to establish the normalized stiffness degradation law has been developed based on rapid fatigue tests by thermography. The non-linear cumulative damage rule has been considered to analyze the damage condition at the beginning of each stress level during rapid fatigue test by thermography. Thus, the test time can be greatly reduced for the determination of this law which is necessary for the prediction of the fatigue life by numerical simulation. The numerical results of the fatigue life prediction for two kinds of multi-directional laminates using stiffness degradation law based on thermographic measurement correlate very well with those obtained from the measurements during classic fatigue tests.

刚度退化规律是碳纤维复合材料疲劳性能预测模型的关键部分。传统的方法来确定这一规律是耗时的,而使用红外辐射(IR)热像仪,刚度退化可以通过应用快速疲劳试验来表征,这需要相当短的时间。然而,在快速疲劳试验中,热成像测量的刚度退化是在多个应力水平和有限循环下进行的。本文将原先针对CFRP单向板提出的经典疲劳试验确定的刚度退化规律推广到多向板。在此基础上,提出了一种基于热成像快速疲劳试验的归一化刚度退化规律建立策略。考虑非线性累积损伤规律,利用热像仪分析快速疲劳试验中各应力水平开始时的损伤情况。这一规律的确定大大缩短了试验时间,为数值模拟预测疲劳寿命提供了必要条件。采用基于热像仪测量的刚度退化规律对两种多向层合板进行疲劳寿命预测的数值结果与经典疲劳试验结果吻合较好。


Computational and experimental studies on lapped bistable composite booms

Chenchen Wu, Jiawei Fan, Kunpeng Guan, Zhongliang Chang, Pengyuan Zhao, Shuai Yue, Liang Li, Dingguo Zhang

doi:10.1016/j.compstruct.2024.118795

搭接双稳复合臂架的计算与实验研究

Lightweight plain-woven fabrics with improved inter-laminar shear properties are suitable candidates for manufacturing bistable reeled composite (BRC) booms that require multiple ultra-thin layers. BRCs are typically constructed with antisymmetrical laminate stacking sequences with certain fibre orientation angles, which introduce laps during the production of extremely long BRCs with plain-woven fabrics. This paper focuses on computational and experimental analyses of lapped plain-woven BRCs during snap through and coiling up. The effects of lap joints on the bistability and damage during snap-through and coiling-up processes for antisymmetrically laminated carbon/epoxy plain-woven BRCs with and without lap joints were investigated. The results indicate that a larger driving force is required for lapped BRCs than for those without lap joints to reach the critical load during snap through, and this requirement increases with increasing lap length. To investigate the damage behaviours of the BRCs during the coiling-up process, strain-gauge measurements and scanning electron microscopy (SEM) tests of the damaged area were conducted. The results show that tensile fracture of the resin is the primary failure mode during equal-sense coiling up, whereas both tensile fracture of the resin and fibre damage occur during opposite-sense coiling up.

具有改进的层间剪切性能的轻质平纹织物是制造需要多个超薄层的双稳态卷绕复合材料(BRC)臂架的合适候选材料。brc通常由具有一定纤维取向角的不对称层压堆叠序列构成,这在用平纹织物生产超长brc时引入了搭接。本文主要对搭接平纹织物BRCs的搭接贯通和卷取过程进行了计算和实验分析。研究了搭接对带搭接和不带搭接的不对称复合碳/环氧平纹编织BRCs的双稳性以及搭接和卷取过程中损伤的影响。结果表明,与未搭接的BRCs相比,搭接BRCs在搭接过程中需要更大的驱动力才能达到临界载荷,并且这一要求随着搭接长度的增加而增加。为了研究BRCs在卷取过程中的损伤行为,对损伤区域进行了应变测量和扫描电子显微镜(SEM)测试。结果表明,等感卷取过程中树脂的拉伸断裂是主要的破坏模式,相反感卷取过程中树脂的拉伸断裂和纤维的拉伸损伤同时发生。


Numerical analysis of particle reinforced composites with interphases by three-dimensional thermal-elasto-plastic Voronoi cell finite element method

Jiangbo Tao, Rui Zhang, Ran Guo

doi:10.1016/j.compstruct.2024.118774

含界面相颗粒增强复合材料三维热弹塑性Voronoi单元有限元数值分析

Research results on linear elasticity problems by the three-dimensional Voronoi cell finite element method (VCFEM) are available. This paper presents a three-dimensional thermo-elasto-plastic VCFEM for analyzing the nonlinear mechanical behavior of particle-reinforced composites containing interphase. The model includes a matrix phase, interphase phase, and inclusion phase, and the three phases satisfy the continuity condition of traction. This paper derives an incrementally modified complementary function and constructs a higher order stress function considering the ellipsoidal interface, which is used in the iterative analysis of the plasticity and thermal problems of three-dimensional Voronoi cells with interphase. Compared with the displacement finite element method, the comparison result pointed out that VCFEM has the advantages of simple mesh generation and fast speed under the same accuracy.

利用三维Voronoi单元法(VCFEM)对线弹性问题进行了研究。提出了一种三维热弹塑性VCFEM方法,用于分析含界面相颗粒增强复合材料的非线性力学行为。该模型包括基体相、间相和夹杂相,三者均满足牵引的连续性条件。本文推导了考虑椭球面界面的增量修正互补函数,构造了高阶应力函数,用于具有界面的三维Voronoi细胞的塑性和热问题的迭代分析。与位移有限元法进行对比,结果表明,在相同精度下,VCFEM具有网格生成简单、速度快的优点。


Composites Part A: Applied Science and Manufacturing

Chemical bridging of ammonium octamolybdate and silica for highly efficient smoke suppression of polyvinyl chloride-based composites

Ting-Ting Suo, Ze-Yong Zhao, Yu-Zhong Wang, Cong Deng

doi:10.1016/j.compositesa.2024.108650

八胺酸铵与二氧化硅的化学桥接用于聚氯乙烯基复合材料的高效抑烟

Smoke hazard is the most dangerous in a fire accident. Cheap inorganic materials such as silica may promote the smoke suppression property of polymer-based composites, but show low efficiency because of chemical inertia in burning scenario. In this work, ammonium octamolybdate (AOM) was chemically incorporated into hydrophobic nano silica (SiO2) with a silane coupling agent as a bridge, and the resulting MSiO2-AOM displayed significantly improved smoke suppression compared with the mixture of SiO2 and AOM. While applying typical polyvinyl chloride wood-plastic building composite (WPC), total smoke production (TSP) and the maximum smoke density (Dsmax) were respectively decreased by 37% and 42% at only 20 phr MSiO2-AOM (5.0 wt%). Herein, the essential reasons for the effect of MSiO2-AOM on overall performance of WPC were also discussed in detail. This work provides an effective method to upgrade the traditional SiO2 to efficient smoke suppressant by a simple bridging effect.

火灾事故中最危险的是烟雾。廉价的无机材料如二氧化硅可以提高聚合物基复合材料的抑烟性能,但由于燃烧时的化学惯性,其抑烟效率较低。本文以硅烷偶联剂为桥接剂,将八胺钼酸铵(AOM)化学掺入疏水性纳米二氧化硅(SiO2)中,得到的八胺钼酸铵(MSiO2-AOM)的抑烟性能明显优于二氧化硅-八胺钼(AOM)的混合物。当使用典型聚氯乙烯木塑建筑复合材料(WPC)时,总产烟量(TSP)和最大烟密度(Dsmax)分别降低37%和42% (MSiO2-AOM为5.0 wt%)。本文还详细讨论了MSiO2-AOM对木复合材料综合性能影响的根本原因。本研究为通过简单的桥接效应将传统SiO2提升为高效抑烟剂提供了一种有效方法。


Study on the parameters optimization of 3D printing continuous carbon fiber-reinforced composites based on CNN and NSGA-II

Jiale Yi, Ben Deng, Fangyu Peng, Aodi Yan, Zhijie Li, Jinguo Shen, Rong Yan, Xiaopeng Xie

doi:10.1016/j.compositesa.2024.108657

基于CNN和NSGA-II的3D打印连续碳纤维增强复合材料参数优化研究

In 3D printing of critical structural components made from continuous carbon fiber-reinforced composites (CCFRC), mechanical performance and manufacturing efficiency are mutually constrained. This paper introduces a novel closed-loop iterative optimization method that swiftly identifies the optimal balance between performance and efficiency for the best overall results. It combines the forecasting capability of Convolutional Neural Networks (CNN) with the optimization strength of Non-dominated Sorting Genetic Algorithm II (NSGA-II). The study found that the optimal parameters as a layup angle of 0°, nozzle temperature of 260 °C, fiber filling density of 80 %, layer thickness of 0.6 mm, and fiber printing speed of 10 mm/s. The results of the optimized process parameters show a 53 % increase in mechanical performance and a 27 % improvement in manufacturing efficiency compared to the sampling experiment results. Therefore, the proposed parameter optimization strategy can quickly determine the optimal process parameters for the given conditions without requiring additional guidance.

在连续碳纤维增强复合材料(CCFRC)关键结构部件的3D打印中,机械性能和制造效率是相互制约的。本文介绍了一种新的闭环迭代优化方法,该方法可以快速识别性能和效率之间的最佳平衡,以获得最佳的总体结果。它结合了卷积神经网络(CNN)的预测能力和非支配排序遗传算法II (NSGA-II)的优化强度。研究发现,最佳参数为铺层角0°,喷嘴温度260 ℃,纤维填充密度80 %,层厚0.6 mm,纤维打印速度10 mm/s。优化后的工艺参数与抽样实验结果相比,机械性能提高了53 %,制造效率提高了27 %。因此,所提出的参数优化策略可以在不需要额外指导的情况下快速确定给定条件下的最优工艺参数。


Composites Part B: Engineering

Composite Scaffolds Based on Egg Membrane and Eggshell-derived Inorganic Particles Promote Soft and Hard Tissue Repair

Zhengchao Yuan, Siyuan Wu, Liwen Fu, Muhammad Shafiq, Yuqing Liang, Peng Li, Xinyi Wang, Hao Feng, Rashida Hashim, Shuqi Lou, Mohamed EL-Newehy, Meera Moydeen Abdulhameed, Weifen Zhang, Xiumei Mo, Shichao Jiang

doi:10.1016/j.compositesb.2024.112071

基于卵膜和蛋壳无机颗粒的复合支架促进软硬组织修复

It is essential to exploit the eggshell membrane (EM) and eggshell (ES) for biomaterial science as a bioresource technology albeit that they are generally considered as waste products of the egg industry. The EM with Janus structural and compositional properties can be prepared into tissue-engineered constructs. The ES was prepared into the inorganic nanoparticles (NPs) namely PCa with an average diameter of 0.67 μm, which was comprised of various inorganic oxides, such as calcium oxide (CaO), and zinc oxide (ZnO). By harnessing the individual advantages of the EM and PCa, they were fabricated into composite scaffolds by a negative pressure inlay method. The composite scaffolds manifested a fibrous network-like structure manifesting large surface area, good mechanical strength (failure force of EM, ca. 1.68 N), biocompatibility and biodegradability in vitro and in vivo. The EM@Ca3 group enabled efficient hemostasis in the liver trauma injury model (hemostasis time, < 32 s), rapid wound healing (96% at day 14), and bone density similar to the normal bone at week 6 post-implantation. Taken together, our approach of leveraging egg-derived bioresource may be worthy for the future investigations of tissue-engineered constructs and potentially other bio-related disciplines.

尽管蛋壳膜(EM)和蛋壳(ES)通常被认为是鸡蛋工业的废物,但将它们作为一种生物资源技术用于生物材料科学是必不可少的。具有Janus结构和组成特性的EM可以制备成组织工程结构。制备了由氧化钙(CaO)、氧化锌(ZnO)等多种无机氧化物组成的平均直径为0.67 μm的无机纳米粒子PCa。利用EM和PCa各自的优势,采用负压镶嵌法制备了复合支架。复合支架呈纤维网状结构,比表面积大,机械强度好(EM破坏力约1.68 N),体外和体内生物相容性和生物降解性好。EM@Ca3组使肝外伤模型有效止血(止血时间< 32 s),伤口愈合迅速(第14天96%),植入后第6周骨密度与正常骨相近。综上所述,我们利用鸡蛋衍生生物资源的方法可能对未来组织工程构建和潜在的其他生物相关学科的研究有价值。


The Effect of Prepreg Ply Thickness in Carbon Fiber Reinforced Composites on Intralaminar Toughness and Shear Strength in Cryogenic Environments for Liquid Hydrogen Storage Tanks

Eduardo Szpoganicz, Fabian Hübner, Uwe Beier, Matthias Geistbeck, Holger Ruckdäschel

doi:10.1016/j.compositesb.2024.112077

碳纤维增强复合材料预浸料厚度对低温环境下液氢储罐层内韧性和剪切强度的影响

This study investigates the effect of prepreg ply thickness on the intralaminar toughness and shear strength of carbon-fiber reinforced polymer (CFRP) in room temperature and cryogenic environments. A toughened epoxy resin, optimized for ultra-low temperatures, was impregnated with unidirectional carbon-fibers at 45, 70, and 140 g/m2 areal weights. The intralaminar energy release rates in modes I and II, along with the interlaminar shear strength, were evaluated under liquid nitrogen (in-situ) testing conditions to assess the performance of these composites in cryogenics. Optical and scanning electron microscopy correlated fiber-matrix distribution and regularity with failure modes and performance. While GIC decreased from 296 K to 77 K, ILSS was notably higher in cryogenic environments. Both intralaminar toughness and interlaminar strength were improved by thinner plies, especially at 77 K. Thus, highlighting the importance of fiber-matrix uniformity in optimizing delamination and shear properties under cryogenic conditions, where sensitivity to irregularities increases.

研究了常温和低温环境下预浸料厚度对碳纤维增强聚合物(CFRP)层间韧性和剪切强度的影响。在一种针对超低温进行了优化的增韧环氧树脂中,分别以45、70和140 g/m2的面积重量浸渍单向碳纤维。在液氮(原位)测试条件下,评估了I和II模式下的层间能量释放率以及层间剪切强度,以评估这些复合材料在低温下的性能。光学和扫描电子显微镜将纤维基质的分布和规律性与失效模式和性能联系起来。当GIC从296 K下降到77 K时,ILSS在低温环境中显著升高。层间强度和层内韧性均随着层厚的增加而提高,尤其是在77 K时。因此,在对不规则性的敏感性增加的低温条件下,强调纤维基质均匀性在优化分层和剪切性能方面的重要性。


Composites Science and Technology

Polytetrafluoroethylene Composites for High-Frequency Microwave Applications: Balancing Thermal Conductivity, Adhesion and Dielectric Properties

Lu He, Pengfei Xu, Yongzheng Zhang, Songgang Chai, Zilong Xie, Zhengli Dou, Ziran Guo, Tianhao Yang, Qiang Fu, Kai Wu

doi:10.1016/j.compscitech.2024.111012

用于高频微波应用的聚四氟乙烯复合材料:平衡导热性、粘附性和介电性能

Polytetrafluoroethylene (PTFE) is widely used as a polymer substrate for high-frequency microwave copper cladding due to its low dielectric loss and high stability. However, its inherently low thermal conductivity requires the use of high-content fillers, which complicates efforts to balance thermal conductivity, adhesion strength, and dielectric loss of the composite materials. Herein, we introduce PTFE composites with a hybrid filler network, where the synergistic alignment and interaction of two-dimensional hexagonal boron nitride (h-BN) and granular β-silicon nitride (Si3N4) forms interconnected pathways in the vertical direction. The spatial arrangement of large-sized h-BN can bridge and shorten the thermal conduction path within the Si3N4 network, forming robust vertical thermal pathways, achieving an out-of-plane thermal conductivity of 1.6 W/m K. Additionally, the complementary properties of h-BN and Si3N4 enhance the overall performance. Si3N4 reduces stress concentration, improving adhesion strength, while h-BN’s wide bandgap and weak polarity help minimize dielectric loss. This combination results in a peeling strength of 1.3 N/mm with copper foil and a remarkably low dielectric loss (<0.0011) at 10 GHz. The ultimate PTFE composite ensures reliable, stable, and secure signal transmission in high-frequency communication devices, making it a highly promising material for the electronics sector.

聚四氟乙烯(PTFE)因其介质损耗低、稳定性高等特点,被广泛用作高频微波铜包覆的聚合物衬底。然而,其固有的低导热性要求使用高含量的填料,这使得平衡复合材料的导热性、粘附强度和介电损耗的努力变得复杂。本文中,我们引入了具有杂化填料网络的PTFE复合材料,其中二维六方氮化硼(h-BN)和颗粒状β-氮化硅(Si3N4)在垂直方向上形成相互连接的路径。大尺寸h-BN的空间布局可以桥接和缩短Si3N4网络内部的热传导路径,形成坚固的垂直热通道,实现1.6 W/m k的面外导热系数。此外,h-BN和Si3N4的互补特性增强了整体性能。Si3N4降低了应力集中,提高了粘附强度,而h-BN的宽带隙和弱极性有助于降低介电损耗。这种组合导致铜箔的剥离强度为1.3 N/mm,并且在10 GHz时具有非常低的介电损耗(<0.0011)。终极聚四氟乙烯复合材料可确保高频通信设备中可靠,稳定和安全的信号传输,使其成为电子行业非常有前途的材料。



来源:复合材料力学仿真Composites FEM
ACTMechanicalOptical疲劳断裂复合材料非线性燃烧化学建筑电子UG通信UM参数优化材料
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【新文速递】2024年12月5日复合材料SCI期刊最新文章

今日更新:Composites Part A: Applied Science and Manufacturing 2 篇,Composites Part B: Engineering 4 篇,Composites Science and Technology 2 篇Composites Part A: Applied Science and ManufacturingCharacterisation of near pure mode II quasi-static and fatigue delamination behaviour of a carbon-glass interface using a pure-moment-loaded DCB test rigIñigo Urcelay Oca, Simon Mosbjerg Jensen, Brian Lau Verndal Bak, Fahimeh Shakibapour, Esben Lindgaarddoi:10.1016/j.compositesa.2024.108625利用纯矩加载DCB试验装置表征碳-玻璃界面的近纯II型准静态和疲劳分层行为This work covers the characterisation of delamination growth in a carbon-glass interface, representative of the one in a wind turbine blade. A pure-moment-loaded Double Cantilever Beam (DCB) test rig is used under quasi-static and fatigue loading. A new fatigue characterisation procedure is adopted by real-time controlling the prescribed energy release rate G . This procedure enables sweeping any desired G range at a user-defined rate independently of the compliance of the specimen. A finite element simulation using a cohesive zone model confirms the testing was performed at near pure mode II conditions. From the quasi-static tests, the onset and steady-state fracture toughnesses are characterised. Fibre bridging is observed, which is believed to explain the characterised R-curve effect. From the fatigue tests, Paris’ law is characterised in a wide G m a x range in each test. The characterisation of the quasi-static and fatigue fracture behaviour of the carbon-glass interface is thus successfully achieved.这项工作涵盖了碳-玻璃界面中分层生长的特征,代表了风力涡轮机叶片中的分层生长。采用纯矩加载双悬臂梁(DCB)试验台进行准静态和疲劳载荷试验。通过实时控制规定的能量释放率G,采用了一种新的疲劳表征方法。该程序能够以用户定义的速率扫描任何所需的G范围,而不受试样的依从性的影响。利用内聚区模型进行的有限元模拟证实了试验是在接近纯模态II条件下进行的。通过准静态试验,分析了初始断裂韧度和稳态断裂韧度。观察到纤维桥接,这被认为解释了特征的r曲线效应。从疲劳试验来看,巴黎定律在每次试验中都具有很宽的gm2 a x范围。因此,碳-玻璃界面的准静态和疲劳断裂行为的表征是成功的。Microstructural Characterisation of fibre-hybrid polymer composites using U-Net on optical imagesJi Dong, Ali Kandemir, Ian Hamertondoi:10.1016/j.compositesa.2024.108569基于光学图像的U-Net表征纤维杂化聚合物复合材料微观结构This study investigates the application of deep learning-based image segmentation using 2D optical imaging for the microstructural characterisation of composite materials with hybridised fibres, offering a potentially cost-effective alternative to computed tomography/3D imaging. Laminates were produced using the HiPerDiF method, combining discontinuous carbon and basalt fibres to reinforce a poly(L-lactic acid) (PLA) matrix. The results demonstrate that the Generalised Dice Loss function significantly outperforms others, particularly in the void class, achieving a 19% improvement in Dice Similarity Score on an unseen dataset for full image characterisation. Similarly, for Boundary Intersection over Union (IoU), which measures the accuracy of local boundary detail capture, the model trained with Generalised Dice Loss achieved 61.4%, compared to 55.0% for the next best model trained with Compound Loss. These findings suggest that regional loss functions are better suited for image-based microstructural characterisation and quality inspection. Additionally, volume fraction, relative fibre and void ratios, and fibre alignment computed from the segmentation results closely match ground truth data. Challenges related to data limitations and variability are also briefly discussed.本研究探讨了基于深度学习的图像分割的应用,使用二维光学成像来表征混合纤维复合材料的微观结构,为计算机断层扫描/3D成像提供了一种潜在的经济可行的替代方案。层压板采用HiPerDiF方法生产,结合不连续的碳和玄武岩纤维来增强聚乳酸(PLA)基质。结果表明,广义骰 子损失函数明显优于其他函数,特别是在void类中,在完整图像表征的未见数据集上,骰 子相似度得分提高了19%。类似地,对于边界交集(IoU),测量局部边界细节捕获的准确性,用广义骰 子损失训练的模型达到了61.4%,而用复合损失训练的下一个最佳模型为55.0%。这些发现表明,区域损失函数更适合于基于图像的微结构表征和质量检测。此外,根据分割结果计算的体积分数、相对纤维和空隙比以及纤维排列与地面真实数据非常吻合。还简要讨论了与数据限制和可变性有关的挑战。Composites Part B: EngineeringA unified strain energy-based fatigue life prediction methodology for composite and metal adhesive joints: Effects of adhesive, geometry and, environmentFernando Castro Sousa, Alireza Akhavan-Safar, Ricardo J.C. Carbas, Eduardo A.S. Marques, Lucas F.M. da Silvadoi:10.1016/j.compositesb.2024.112022基于应变能的复合材料和金属粘接接头疲劳寿命预测方法:粘接、几何和环境的影响Ensuring the efficiency and safety of bonded structures across diverse engineering sectors requires a robust fatigue model for adhesive joints in both composite and metal substrates. This study presents a unified fatigue life prediction methodology for similar and dissimilar composite and metal adhesive joints. The proposed model integrates hydrostatic and deviatoric strain energy density components with the theory of critical distances. The model has been validated against diverse experimental data from different joint geometries, loading conditions, and different environments. The linear-elastic assumption is sufficient for toughened epoxies, whereas an elastoplastic model is necessary for ductile methacrylate adhesives. Calibration based on a single fatigue test yields the highest accuracy, while quasi-static test calibration is also satisfactory. The methodology addresses diverse loading conditions and environmental factors, showing a strong correlation with experimental results. It advances the performance, design, and reliability of similar and dissimilar composite to metal adhesive joints.为了确保不同工程领域的粘合结构的效率和安全性,需要针对复合材料和金属基板的粘合接头建立一个强大的疲劳模型。提出了一种统一的相似和不同复合材料和金属粘接接头疲劳寿命预测方法。该模型将流体静力和偏应变能密度分量与临界距离理论相结合。该模型已通过不同节点几何形状、加载条件和不同环境的实验数据进行了验证。对于增韧环氧树脂,线弹性假设是足够的,而对于延性甲基丙烯酸酯胶粘剂,弹塑性模型是必要的。基于单一疲劳试验的校准精度最高,而准静态试验校准也令人满意。该方法考虑了不同的加载条件和环境因素,与实验结果有很强的相关性。它提高了相似和不同复合材料对金属粘合接头的性能、设计和可靠性。Preparation of energy-efficient, environmentally friendly and high-strength biocomposites from wood fibre ultramicro self-composite cellulose matricesMingTao Bai, Yang Yang, Lei Zhang, HongFei Huo, Jijuan Zhang, Zhifeng Wang, Zhongfeng Zhangdoi:10.1016/j.compositesb.2024.112047 木纤维超微自复合纤维素基质制备节能环保高强生物复合材料Considering the diminishing forest as a natural resource, the efficient use of small-diameter shrubs is crucial for global sustainable development. This approach has significant potential to prevent wasting forest resources and reduce carbon emissions. However, small-diameter timber has inherent drawbacks, such as the looseness of this material, susceptibility to cracking and deformation, and low strength, all of which significantly impact its range of applications. In this study, an efficient, green method was developed to prepare adhesive-free biocomposites from discarded small-diameter shrubs via ultrasonic pretreatment and thermoforming. After the ultrasonic pretreatment, the flexural and tensile strengths of the biocomposites increased by 145% and 132%, respectively. Ultrasonic pretreatment separated and destroyed chemical bonds among the lignocellulosic biomass macromolecules through high-speed shear and microjets. This process significantly increased the amount of binding sites on the cellulose fibres, and further densified the cell walls through hot pressing. Moreover, the ultrasonic pretreatment may remove components of the wood flour that act as fillers or density enhancers, resulting in a reduction in the density of the biocomposite. Simultaneously, lignin acted as a binder and improved fibre bonding through both physical and chemical cross-linking, resulting in a dense cellulose structure with a three-dimensional lattice structure and a less hydrophilic surface, as evidenced by a water contact angle of 81.72°. In addition, the high-quality, binder-free biocomposites did not emit harmful gases such as formaldehyde. Hence, they are expected to become sustainable materials for building decoration and furniture applications in the future.考虑到森林作为一种自然资源的日益减少,小直径灌木的有效利用对全球可持续发展至关重要。这种方法在防止森林资源浪费和减少碳排放方面具有巨大潜力。然而,小直径木材具有固有的缺点,例如材料的松散,易开裂和变形,强度低,所有这些都严重影响了其应用范围。本研究开发了一种高效、绿色的方法,通过超声波预处理和热成型,从废弃的小直径灌木中制备无粘合剂生物复合材料。经超声预处理后,生物复合材料的抗弯强度和拉伸强度分别提高了145%和132%。超声波预处理通过高速剪切和微射流分离和破坏木质纤维素生物质大分子之间的化学键。这一过程显著增加了纤维素纤维上结合位点的数量,并通过热压使细胞壁进一步致密化。此外,超声波预处理可以去除木粉中作为填料或密度增强剂的成分,从而导致生物复合材料密度的降低。同时,木质素作为粘合剂,通过物理交联和化学交联改善纤维的结合,使纤维素结构致密,具有三维晶格结构,表面亲水性较低,水接触角为81.72°。此外,这种高质量、无粘合剂的生物复合材料不会释放甲醛等有害气体。因此,它们有望成为未来建筑装饰和家具应用的可持续材料。Enhanced carbon fiber interface with thermoplastics via nanostructure surface modification: failure, morphology and wettability analysisWeiqing Fang, Adam Pearson, Yige Huang, Hani E. Naguibdoi:10.1016/j.compositesb.2024.112054 通过纳米结构表面改性增强碳纤维与热塑性塑料的界面:失效、形貌和润湿性分析Improving the fiber-matrix adhesion in thermoplastic composites remains a significant challenge due to the lack of chemical bonding between thermoplastics and common reinforcing fibers. This study investigates the effectiveness of carbon fibers enhanced with nanostructure surface modification for strengthening the interfacial adhesion to thermoplastic matrices. The fiber surface was modified with graphene nanoplatelets (GNP) through the facile coating method, and the apparent interfacial shear strength (IFSS) was determined by the single-fiber pullout test. GNP-coated fiber improved IFSS by 74% with neat high-density polyethylene (HDPE-Neat) and 28% with maleic anhydride-grafted HDPE (HDPE-8MA), while reduced by 27% with polyamide 6 (PA6) due to different failure mechanisms. Morphology, chemical, and wettability analysis were conducted on the nano-enhanced carbon fibers to quantitatively elucidate these findings on micro/nanoscale, combining machine learning-based image segmentation, X-ray photoelectron spectroscopy (XPS), and contact-angle measurements of intermittent beading on fibers.由于热塑性塑料与普通增强纤维之间缺乏化学结合,提高热塑性复合材料中纤维-基体的粘附性仍然是一个重大挑战。本研究考察了纳米结构表面改性增强碳纤维与热塑性基体界面粘附的有效性。用石墨烯纳米薄片(GNP)通过易涂法对纤维表面进行改性,并通过单纤维拉拔试验测定纤维的表观界面剪切强度(IFSS)。采用纯高密度聚乙烯(HDPE- neat)和马来酸酐接枝HDPE (HDPE- 8ma)分别提高了74%和28%的IFSS,而采用聚酰胺6 (PA6)由于失效机制的不同,使IFSS降低了27%。结合基于机器学习的图像分割、x射线光电子能谱(XPS)和纤维上间歇性珠状的接触角测量,对纳米增强碳纤维进行了形态学、化学和润湿性分析,以在微/纳米尺度上定量阐明这些发现。Controllable fabrication of the luminescent photocatalytic material AgB/SMSO for application in cement: Optimization of doping strategies and all-weather degradation of pollutantsXinjie Cai, Yidong Xudoi:10.1016/j.compositesb.2024.112060水泥用发光光催化材料AgB/SMSO的可控制备:掺杂策略优化及污染物全天候降解This paper presents an innovative luminescent photocatalytic material, Ag3PO4/BiVO4/Sr2MgSi2O7:(Eu2+, Dy3+) (AgB/SMSO), which overcomes a pivotal limitation of photocatalysts—dependence on a light source—and effectively remediates pollutants and augments cement-based composite properties. The efficient carrier separation facilitated by Ag3PO4, in conjunction with the broad spectral response of BiVO4, enables AgB/SMSO to harness the internal luminescent properties of SMSO as a persistent light source, achieving continuous degradation of pollutants, which reveals the exceptional afterglow characteristics and photocatalytic activity of AgB/SMSO. At a 1:1:40 ratio, AgB/SMSO maintained its catalytic efficacy for over 8 h in the dark (methylene blue degradation rate of 70.43%), surpassing the 3-hour limit of current luminescent photocatalysts. Furthermore, the impact of integrating AgB/SMSO with cement on early-stage cement hydration, morphology, and micromechanical properties was comprehensively assessed. Ultimately, the overall photocatalytic capability of the derived AgB/SMSO cement-based composites was evaluated through experiments, revealing the synergistic mechanisms involved. This study not only enriches the theoretical understanding of photocatalysis but also provides a robust technical foundation for the innovation of environmentally friendly building materials and the advancement of sustainable urban development.本文提出了一种创新的发光光催化材料Ag3PO4/BiVO4/Sr2MgSi2O7:(Eu2+, Dy3+) (AgB/SMSO),它克服了光催化剂依赖光源的关键限制,有效地修复了污染物并增强了水泥基复合材料的性能。Ag3PO4促进了高效的载流子分离,结合BiVO4的广谱响应,使AgB/SMSO能够利用SMSO的内部发光特性作为持续光源,实现污染物的连续降解,这揭示了AgB/SMSO独特的余辉特性和光催化活性。在1:1:40的比例下,AgB/SMSO在黑暗中保持了8 h以上的催化效果(亚甲蓝降解率为70.43%),超过了目前发光光催化剂3小时的极限。此外,还综合评估了AgB/SMSO与水泥的掺入对水泥早期水化、形态和微观力学性能的影响。最后,通过实验评估了衍生的AgB/SMSO水泥基复合材料的整体光催化能力,揭示了所涉及的协同机制。本研究不仅丰富了光催化的理论认识,而且为环保建筑材料的创新和城市可持续发展的推进提供了坚实的技术基础。Composites Science and TechnologyInfluence of expansion ratio and multilayered gradient structure on the electromagnetic interference shielding performance of lightweight poly (lactic acid)/carbon nanostructures composite foamsQian Ren, Youquan Wei, Xueyun Li, Cao Yu, Long Wang, Bin Shen, Wenge Zhengdoi:10.1016/j.compscitech.2024.110992 膨胀率和多层梯度结构对轻质聚乳酸/碳纳米复合泡沫电磁干扰屏蔽性能的影响Cellular structures incorporated in conductive polymer composites (CPC) are gaining recognition as a promising alternative to traditional metal materials for electromagnetic interference (EMI) shielding applications, owing to their outstanding properties and lightweight nature. In this study, the polylactic acid (PLA)/carbon nanostructure (CNS) composite foam with a multilayered gradient structure was prepared by supercritical carbon dioxide (CO2) foaming technology. The original size of the sample, saturation pressure, and foaming temperature had obvious effects on the foaming behavior of the PLA/CNS composite. In the prepared multilayered gradient-structured sample, the CNS content increased layer by layer (from 1 wt% to 7 wt%), and its density could be as low as 0.22 g/cm³. In addition, the EMI SE value of the prepared sample could be as high as 51.8 dB with an absorption coefficient of 0.85, thus providing superior EMI shielding performance. This result indicated that high-performance and lightweight polymer-based shielding materials could be obtained by preparing multilayered gradient-structured foam samples, which have broad application prospects in aerospace and electronics.导电性聚合物复合材料(CPC)的细胞结构由于其优异的性能和轻便的特性,被认为是传统金属材料在电磁干扰(EMI)屏蔽应用中的一种有前途的替代品。本研究采用超临界二氧化碳(CO2)发泡技术制备了具有多层梯度结构的聚乳酸(PLA)/碳纳米结构(CNS)复合泡沫材料。样品的原始尺寸、饱和压力和发泡温度对PLA/CNS复合材料的发泡行为有明显的影响。在制备的多层梯度结构样品中,CNS含量逐层增加(从1 wt%增加到7 wt%),其密度可低至0.22 g/cm³。此外,制备的样品的EMI SE值可高达51.8 dB,吸收系数为0.85,具有优异的EMI屏蔽性能。这一结果表明,制备多层梯度结构泡沫样品可以获得高性能轻质聚合物基屏蔽材料,在航空航天和电子领域具有广阔的应用前景。Enhanced Electromagnetic Wave Absorption and Thermal Conductivity in Epoxy Composites with a Heterostructure-Rich 3D MoS₂/CMF Network FrameworkHaoran Geng, Long Zhao, Jing Deng, Jingru Chen, Yihao Fan, Qingyun Zhao, Hongxing Gui, Jianhe Liao, Yanfang Zhao, Yongxin Qian, Guizhen Wangdoi:10.1016/j.compscitech.2024.110993 具有丰富异质结构的三维MoS 2 /CMF网络框架的环氧复合材料的电磁波吸收和导热性With the widespread application of highly integrated and high-frequency power devices in the electronics field, traditional electronic packaging materials can no longer effectively resist the harm caused by electromagnetic interference and heat accumulation to electronic equipment. To address these challenges, we have successfully constructed a heterostructure-rich dual-level three-dimensional (3D) network framework (MoS2/CMF) by effectively integrating molybdenum disulfide (MoS2) with carbonized melamine foam (CMF). These fillers were then composited with epoxy resin (EP) to develop MoS2/CMF/EP composites exhibiting both electromagnetic wave absorption (EMA) and enhanced thermal conductivity. Specifically, two-dimensional (2D) MoS2 nanosheets with a 1T/2H-phase structure uniformly grew on the surface of CMF, improving the poor impedance characteristics of the 3D carbon structure and increasing heterointerfaces and multiple scattering abilities. Owing to the synergistic effects of attenuation performance and impedance matching, the EP-based MoS2/CMF-1 composite demonstrated an impressive reflection loss value of -64.80 dB and an effective absorption bandwidth of 8.48 GHz, achieved with only a 5 wt.% loading. Correspondingly, CST simulation results indicated that when electromagnetic waves are vertically incident on MoS2/CMF-1/EP samples, the radar cross-section (RCS) attenuation value can reach up to 35.4 dBm2. Moreover, the highly interconnected 3D carbon structure of CMF provides broad pathways for phonon transport, resulting in the thermal conductivity of MoS2/CMF-1/EP reaching 0.41 W/m·K at room temperature, a nearly 141% improvement compared to pure EP. This multifunctional EP-based composite, with its high-efficiency EMA and thermal management performance, shows great potential for application in the packaging of highly integrated electronic devices.随着高集成度、高频功率器件在电子领域的广泛应用,传统的电子封装材料已不能有效抵御电磁干扰和热量积累对电子设备造成的危害。为了解决这些挑战,我们通过将二硫化钼(MoS2)与碳化三聚氰胺泡沫(CMF)有效整合,成功构建了富含异质结构的双层三维(3D)网络框架(MoS2/CMF)。然后将这些填料与环氧树脂(EP)复合,制备出具有电磁波吸收(EMA)和增强导热性的MoS2/CMF/EP复合材料。具体而言,具有1T/ 2h相结构的二维(2D) MoS2纳米片在CMF表面均匀生长,改善了三维碳结构的阻抗特性,增加了异质界面和多次散射能力。由于衰减性能和阻抗匹配的协同效应,基于ep的MoS2/CMF-1复合材料显示出令人印象深刻的反射损耗值为-64.80 dB,有效吸收带宽为8.48 GHz,负载仅为5.wt .%。相应的,CST仿真结果表明,电磁波垂直入射到MoS2/CMF-1/EP样品上,雷达截面(RCS)衰减值可达35.4 dBm2。此外,高度互连的CMF三维碳结构为声子输运提供了广阔的途径,导致MoS2/CMF-1/EP在室温下的导热系数达到0.41 W/m·K,比纯EP提高了近141%。这种多功能ep基复合材料具有高效的EMA和热管理性能,在高度集成的电子器件封装中显示出巨大的应用潜力。来源:复合材料力学仿真Composites FEM

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