今日更新:Composite Structures 1 篇,Composites Part A: Applied Science and Manufacturing 3 篇,Composites Part B: Engineering 2 篇,Composites Science and Technology 3 篇
A multiscale interfacial cyclic debonding model for fibre-reinforced composites using micromechanics and molecular dynamics
Danhui Yang, Yu Sun, Jin Zhou, Gongshuai Wei, Zhongwei Guan, Xuefeng Chen
doi:10.1016/j.compstruct.2023.117831
利用微力学和分子动力学建立纤维增强复合材料的多尺度界面循环脱粘模型
In this study, a novel multiscale model based on the finite-volume direct averaging micromechanics (FVDAM) theory and molecular dynamics (MD) was developed to predict the interfacial cyclic debonding behaviour of composites. At the microscale, a solid interface with accumulated damage was incorporated using FVDAM, which enabled the simulation of both localised and homogenised interfacial damage responses under cyclic loading; a significant reduction in strength was observed after 10 loading cycles, implying the interfacial damage accumulation. At the atomic-scale, an interface model was built and subjected to cyclic loadings using MD simulation; the stress peak after 5 cycles was approximately half of the initial value, which provides damage parameters for upper-scale calculations and reveals the fundamental mechanism of interfacial cyclic debonding. The experimental data of unidirectional SCS-6/Ti-15-3 composites under cyclic loading were adopted to verify the proposed model. Furthermore, the influence of thermal residual stress and fibre orientation was investigated, which offers valuable insights for composite design and manufacturing.
本研究基于有限体积直接平均微观力学(FVDAM)理论和分子动力学(MD)开发了一种新型多尺度模型,用于预测复合材料的界面循环脱粘行为。在微观尺度上,使用 FVDAM 将具有累积损伤的固体界面纳入其中,从而能够模拟循环加载下的局部和均匀界面损伤响应;在 10 个加载周期后观察到强度显著降低,这意味着界面损伤累积。在原子尺度上,建立了界面模型,并利用 MD 模拟对其进行循环加载;5 个循环后的应力峰值约为初始值的一半,这为上尺度计算提供了损伤参数,并揭示了界面循环脱粘的基本机制。采用循环加载下单向 SCS-6/Ti-15-3 复合材料的实验数据验证了所提出的模型。此外,还研究了热残余应力和纤维取向的影响,为复合材料的设计和制造提供了有价值的见解。
Reactive Extrusion Additive Manufacturing of a Short Carbon Fiber Thermosetting Composite via Active Mixing
Pratik Koirala, Robert Pavlovic, Athena Aber, Michael J. Fogg, Cole Mensch, Carolyn C. Seepersad, Mehran Tehrani
doi:10.1016/j.compositesa.2023.107989
通过活性混合实现短碳纤维热固性复合材料的反应挤出增材制造
Reactive extrusion additive manufacturing (REAM) is a recently developed process that utilizes reactive thermoset resin-hardener systems that are mixed inside a shearing element, deposited layer by layer to form a structure, and cured in-situ without external energy. An externally powered active mixing element was developed and used to demonstrate REAM with a highly viscous resin that was filled with 10 wt.% chopped carbon fibers. This was achieved by adding fumed silica and increasing the temperature of the fiber-resin mixture to enable effective in-situ mixing while maintaining shape retention upon deposition. Tensile properties of fiber-reinforced and reference REAM parts were measured and explained using their fiber alignment and length distribution. Finally, a mechanics model was utilized to determine the optimal short fiber content for strength and stiffness, considering the degradation of fiber length at higher volume fractions due to the mixing.
反应挤压增材制造(REAM)是最近开发的一种工艺,它利用反应热固性树脂-固化剂系统在剪切元件内混合,逐层沉积形成结构,并在无外部能量的情况下就地固化。我们开发了一种外部驱动的活性混合元件,并用它来演示 REAM 与高粘度树脂的混合,其中填充了 10 wt.% 的切碎碳纤维。这是通过添加气相二氧化硅和提高纤维-树脂混合物的温度来实现的,从而实现有效的原位混合,同时在沉积时保持形状不变。测量了纤维增强部件和参考 REAM 部件的拉伸性能,并利用其纤维排列和长度分布进行了解释。最后,利用力学模型确定了强度和刚度的最佳短纤维含量,同时考虑到了混合造成的较高体积分数下的纤维长度退化。
Converting bio-waste rice into ultralight hierarchical porous carbon to pack polyethylene glycol for multifunctional applications:Experiment and molecular dynamics simulations
Pei Li, Daili Feng, Yanhui Feng, Xinxin Zhang
doi:10.1016/j.compositesa.2023.107979
将生物废料稻米转化为超轻分层多孔碳,以封装聚乙二醇,实现多功能应用:实验与分子动力学模拟
A structural-functional integrated shape-stabilized composite phase change material (PCM) was synthesized by converting biowaste rice into ultralight (0.08 g/cm3) hierarchical porous carbon (CNR) to pack polyethylene glycol (PEG) PCM. The thermal property and corresponding mechanism were analyzed. The results show that the composite PCM exhibits excellent thermal storage efficiency (93.3%), considerable solar photothermal conversion efficiency and superior thermal stability. The interfacial thermal resistance (ITR) of PEG/CNR is 73% lower than graphene foam-based composite PCM thus a fast transient temperature response. Particularly, the package of PEG endowed composite PCM with elastic characteristic thereby an enhanced compressive strength. Furthermore, covering PEG/CNR results in a delay of approximately 1.3 times in reaching the peak temperature on the surface of electronic components, and a delay of 5 times in cooling time. This study presents solid guidelines for societal development that is sustainable and makes some recommendations for construction of composite PCMs combining multifunctional applications.
通过将生物废料大米转化为超轻(0.08 g/cm3)分层多孔碳(CNR)来封装聚乙二醇(PEG)PCM,合成了一种结构功能一体化的形状稳定复合相变材料(PCM)。对其热性能和相应的机理进行了分析。结果表明,复合 PCM 具有出色的蓄热效率(93.3%)、可观的太阳能光热转换效率和卓越的热稳定性。PEG/CNR 的界面热阻(ITR)比基于石墨烯泡沫的复合 PCM 低 73%,因此具有快速的瞬态温度响应。特别是,PEG 包裹赋予了复合 PCM 弹性特性,从而提高了抗压强度。此外,覆盖 PEG/CNR 可使电子元件表面达到峰值温度的时间延迟约 1.3 倍,冷却时间延迟 5 倍。本研究为社会的可持续发展提供了可靠的指导方针,并为构建多功能应用的复合 PCM 提出了一些建议。
Interfacial engineering of hybrid MXene-Ni-CF tri-core-shell composites for electromagnetic interference shielding and E-heating applications
Yi Hu, Guoyu Yang, Junzhen Chen, Yujun Li, Ming Dong, Han Zhang, Emiliano Bilotti, Jianjun Jiang, Dimitrios G. Papageorgiou
doi:10.1016/j.compositesa.2023.107990
用于电磁干扰屏蔽和电加热应用的混合 MXene-Ni-CF 三核壳复合材料的界面工程设计
In response to the the needs for multifunctional carbon fiber reinforced polymer (CFRP) composites, we present a novel, tri-core-shell CFRP consisting of MXene, nickel (Ni), and CF synthesized throughlayer-by-layer assembly. The hybridcomposites demonstrate remarkable electrical conductivity and electromagnetic interference (EMI) shielding, alongside efficient electrical (E-) heating properties. Additionally, the MXene-Ni-CF/EP hybrid composite displayed improved flexural strength and ILSS compared to Ni-CF/EP composite. Outstanding enhancements were observed in both the through-thickness and in-plane electrical conductivities, with a 116-fold and 14-fold improvement, respectively, attributed to the complex MXene-Ni-CF conductive paths. The hierarchical compositessignificantly outperformed the state of the art and demonstrated a superior EMI shielding efficiency of 72.4 dB by virtue of the dielectric and magnetic loss mechanisms. Thelow-voltage-driven E-heating capacity could be utilized for de-icing applications due to the thermally conductive networks. The producedcomposites offer a highly promising solution to tackle challenges associated with lightning strikes and icy weather conditions, while also aligning with the goal of cost-effective industrial production.
为了满足对多功能碳纤维增强聚合物(CFRP)复合材料的需求,我们提出了一种新型三核壳 CFRP,由 MXene、镍(Ni)和 CF 通过逐层组装合成。这种混合复合材料具有出色的导电性、电磁干扰(EMI)屏蔽性和高效的电热(E-)性能。此外,与 Ni-CF/EP 复合材料相比,MXene-Ni-CF/EP 混合复合材料显示出更高的抗弯强度和 ILSS。由于 MXene-Ni-CF 复合导电路径的存在,通厚导电率和面内导电率都得到了显著提高,分别提高了 116 倍和 14 倍。分层复合材料的性能明显优于目前的技术水平,并凭借介电和磁损耗机制表现出 72.4 dB 的卓越 EMI 屏蔽效率。由于具有导热网络,低电压驱动的电热能力可用于除冰应用。所生产的复合材料为应对与雷击和冰雪天气条件相关的挑战提供了一种极具前景的解决方案,同时也符合成本效益工业生产的目标。
Multinanolayered PA6/Cloisite and PE/PA6/Cloisite composites: Structure, mechanical and barrier properties
Stéphane Marais, Quentin Lozay, Nadège Follain, Jérémie Soulestin, Nicolas Couvrat, Eric Dargent
doi:10.1016/j.compositesb.2023.111167
多纳层 PA6/Cloisite 和 PE/PA6/Cloisite 复合材料:结构、机械和阻隔性能
Economic and environmental challenges are driving development towards more efficient and lighter materials. Polyethylene (PE) and polyamide (PA6) are among the most used polymers and their assembly in multilayer make them efficient protective materials. The aim of this work is to design new multilayer composite films based on polyethylene and polyamide with high barrier properties. A coextrusion process with layer multiplier elements (LME) made it possible to carry out 100 μm-thick multilayer films containing 5 up to 1025 layers. Loaded PE/PA6 multilayer films were made by incorporating Cloisite particles (organo-modified montmorillonite – C30B) at 5 wt% into the PA6 layers. For comparison PA6 films with and without fillers were also made by using the same coextrusion process. The structural and thermal properties of all multilayer films were correlated with the water and gas barrier properties. A good dispersion of exfoliated C30B in the PA6 phase was observed even for the thinnest confined layers of PA6 in PE/PA6 multilayers (∼90 nm). We showed the complexity of the multinanolayer structures involving interphases as well as the complexity of the transfer mechanisms. The serial model used for predicting permeability highlighted some significant improvements of the gas barrier properties of confined PA6 layers. The barrier effect on all the multilayer films was, however, limited due to the “on-edge” orientation of the crystalline phases and structural defects induced during the coextrusion process. Despite this, the confinement of nanofillers in PA6 multilayers and in PA6 layers of PE/PA6 multilayers allowed to increase the barrier properties of multilayers.
经济和环境方面的挑战促使人们向更高效、更轻质的材料发展。聚乙烯(PE)和聚酰胺(PA6)是最常用的聚合物之一,它们的多层组合使其成为高效的防护材料。这项工作的目的是以聚乙烯和聚酰胺为基础,设计出具有高阻隔性能的新型多层复合薄膜。采用层乘法元件(LME)的共挤工艺,可以生产出厚度为 100 μm 的多层薄膜,层数从 5 层到 1025 层不等。通过在 PA6 层中加入 5 wt% 的 Cloisite 颗粒(有机改性蒙脱石 - C30B),制成了负载 PE/PA6 多层薄膜。为了进行比较,还采用相同的共挤工艺制作了含填料和不含填料的 PA6 薄膜。所有多层薄膜的结构和热性能都与水和气体阻隔性能相关。即使在 PE/PA6 多层膜中最薄的 PA6 封闭层(∼90 nm)中,也能观察到剥离的 C30B 在 PA6 相中的良好分散。我们展示了涉及相间的多层结构的复杂性以及转移机制的复杂性。用于预测渗透性的序列模型突出显示了密闭 PA6 层气体阻隔性能的一些显著改善。然而,由于结晶相的 "边缘 "取向以及共挤过程中产生的结构缺陷,所有多层薄膜的阻隔效果都受到了限制。尽管如此,纳米填料在 PA6 多层膜和 PE/PA6 多层膜的 PA6 层中的限制作用还是提高了多层膜的阻隔性能。
Silk fibroin/polyacrylamide-based tough 3D printing scaffold with strain sensing ability and chondrogenic activity
Yanan Geng, Tiexin Liu, Menglu Zhao, Haifeng Wei, Xiang Yao, Yaopeng Zhang
doi:10.1016/j.compositesb.2023.111173
基于丝纤维素/聚丙烯酰胺的具有应变传感能力和软骨活性的坚韧 3D 打印支架
Cartilage tissue plays an important role in our life activities. The poor self-repair capacity makes cartilage tissue engineering an urgent clinical demand. Among them, the development of tissue engineering scaffolds with both biomimetic features and microenvironment signal sensing abilities could significantly promote the development of cartilage tissue engineering. While most of the reported cartilage scaffolds have no intelligent sensing features. Herein, a ternary composite 3D printing scaffold with both strain sensing ability and desired mechanical property was developed, by using regenerated silk fibroin (RSF) and polyacrylamide (PAM) as main matrixes, and oxidized bacterial cellulose nanofibers (OBC) as filler. Then, the mechanical property, strain sensing ability and corresponding ectopic chondrogenic activity of the RSF/PAM/OBC 3D printing scaffold were comprehensively investigated and verified through in vitro and in vivo studies. Results showed that the RSF/PAM/OBC (OBC-6.3 wt%) scaffold owns effective strain sensing property and desired ectopic chondrogenesis capabilities in the subcutaneous microenvironment. It could be used for reliable monitoring the joint movements, related motion amplitudes, and also promoting the cartilage specifical genes expression. These features not only confirmed the great potential of these smart scaffolds for applications in tissue reconstruction and mechanical stimulus monitoring of the corresponding tissue microenvironment, but also proved the possibility of employing various 3D printing scaffolds as flexible bioelectronics.
软骨组织在我们的生命活动中发挥着重要作用。软骨组织自我修复能力差,因此软骨组织工程成为临床的迫切需求。其中,具有生物仿生功能和微环境信号传感能力的组织工程支架的开发将极大地促进软骨组织工程的发展。而目前报道的软骨支架大多不具备智能传感功能。本文以再生蚕丝纤维素(RSF)和聚丙烯酰胺(PAM)为主要基质,以氧化细菌纤维素纳米纤维(OBC)为填充物,开发了一种兼具应变传感能力和理想力学性能的三元复合3D打印支架。然后,通过体外和体内研究全面考察和验证了RSF/PAM/OBC三维打印支架的力学性能、应变传感能力和相应的异位软骨活性。结果表明,RSF/PAM/OBC(OBC-6.3 wt%)支架在皮下微环境中具有有效的应变传感特性和理想的异位软骨生成能力。它可用于可靠监测关节运动和相关运动幅度,还能促进软骨特异性基因的表达。这些特点不仅证实了这些智能支架在组织重建和相应组织微环境的机械刺 激监测方面的巨大应用潜力,还证明了将各种三维打印支架用作柔性生物电子器件的可能性。
Energy release rate for steady-state fiber debonding in structural battery composites
Kai Guo, N. Sridhar, Choon Chiang Foo, Bharathi Madurai Srinivasan
doi:10.1016/j.compscitech.2023.110416
电池结构复合材料稳态纤维脱粘的能量释放率
Structural battery composites are multifunctional materials intended to provide energy storage capacity while maintaining their strength and load bearing capacity under significant mechanical loads. In this study, we investigate the mechanics of carbon fiber debonding, a critical failure mechanism in structural battery composites. The carbon fibers are intended to serve both as an electrochemically active material and to bear mechanical load in the composite system. We derive an analytical solution to the energy release rate for steady-state fiber debonding for different electrochemical and mechanical loading cases with the aid of the classical solution for the Eshelby inclusion problem. The analytical solutions are validated with finite element simulations. We find a higher energy release rate and thus a greater driving force for fiber debonding is caused either by a lower lithium concentration in the fiber and/or by greater transverse mechanical loads such as biaxial tension or shear applied at the far field in the matrix. We find that the model is predictive even for transversely isotropic fibers despite the assumption that the fiber is elastically isotropic in the model. This work can provide guidance for the design of mechanically robust structural batteries.
结构电池复合材料是一种多功能材料,旨在提供储能能力,同时在巨大的机械负荷下保持强度和承载能力。在本研究中,我们对结构性电池复合材料中的一个关键失效机理--碳纤维脱粘进行了力学研究。碳纤维既是电化学活性材料,也是复合材料系统中的机械载荷。我们借助埃舍尔比包容问题的经典解决方案,得出了不同电化学和机械负载情况下稳态纤维脱胶能量释放率的分析解决方案。有限元模拟验证了分析解。我们发现,由于纤维中的锂浓度较低,和/或由于在基体远场施加了更大的横向机械负荷(如双轴拉力或剪切力),纤维的能量释放率较高,因此纤维脱胶的驱动力较大。我们发现,尽管在模型中假设纤维是弹性各向同性的,但该模型甚至对横向各向同性纤维也具有预测性。这项工作可为设计机械坚固的结构电池提供指导。
A three-dimensional failure criterion model considering the effects of fiber misalignment on longitudinal tensile failure
Naiyu Liu, Puhui Chen
doi:10.1016/j.compscitech.2023.110424
考虑纤维错位对纵向拉伸失效影响的三维失效准则模型
This paper proposes a three-dimensional failure criterion model for unidirectional fiber-reinforced composites. In contrast to previous models that only accounted for the effect of fiber misalignment in the presence of longitudinal compressive stress, the proposed failure criterion model comprehensively considers the effect of localized misaligned regions on the failure under any stress state. Another key contribution of this study is the introduction of the effective misalignment angle. Considering effective misalignment angles, the proposed failure criterion model can reasonably reveal the effect of localized misaligned regions on the failure behavior under different stress states. The agreement between the predicted results and the experimental data proves that the proposed model has good applicability. Furthermore, the influence of initial misalignment angles on failure is analyzed under varying stress conditions. The results indicate that even under longitudinal tensile stress, the initial misalignment angle still plays an important role in the failure behavior of materials.
本文提出了单向纤维增强复合材料的三维失效准则模型。与以往仅考虑纵向压应力作用下纤维错位影响的模型不同,本文提出的失效准则模型全面考虑了任何应力状态下局部错位区域对失效的影响。本研究的另一个重要贡献是引入了有效错位角。考虑到有效错位角,所提出的失效准则模型可以合理地揭示局部错位区域在不同应力状态下对失效行为的影响。预测结果与实验数据之间的一致性证明了所提出的模型具有良好的适用性。此外,还分析了在不同应力条件下初始错位角对破坏的影响。结果表明,即使在纵向拉伸应力下,初始错位角仍对材料的破坏行为起着重要作用。
Modelling the damage evolution in unidirectional all-carbon hybrid laminates
Amaury Ollic, Fariborz Sheibanian, Babak Fazlali, Yentl Swolfs, Stepan V. Lomov, Valter Carvelli
doi:10.1016/j.compscitech.2023.110420
单向全碳混合层压板损伤演变建模
Hybrid reinforcements for composites have been extensively studied and adopted to overcome the lack of ductility via pseudo-ductility. Thin-ply all-carbon interlayer hybrid laminates have attracted attention for their peculiar pseudo-ductile tensile response. At the same time, conventional thick plies have been barely considered. This work developed a finite element model to simulate the complex tensile damage scenario of unidirectional thin- and thick-ply all-carbon interlayer hybrid laminates. The damage modes intended in the numerical model were fragmentation in the low-elongation (LE) plies, and delamination of LE and high-elongation (HE) ply interfaces. Thin- and thick-ply hybrid laminates were modelled and compared to available experiments. The numerical model was also adopted to simulate different layups to predict the effect of LE thickness fraction on the pseudo-ductile tensile behaviour and the evolution of damage modes. As suggested in the literature, the results allowed us to depict the damage mode map of the considered hybrid laminates. The map distinguishes the all-carbon hybrid laminate configurations with pseudo-ductile and brittle tensile responses.
为了通过假韧性克服延展性不足的问题,人们对复合材料的混合增强材料进行了广泛的研究和采用。薄层全碳夹层混合层压板因其奇特的假延展拉伸响应而备受关注。与此同时,传统的厚层板几乎没有被考虑。本研究开发了一种有限元模型,用于模拟单向薄层和厚层全碳夹层混合层压板的复杂拉伸损伤情况。数值模型中的损伤模式为低伸长率(LE)层的碎裂以及 LE 和高伸长率(HE)层界面的分层。对薄层和厚层混合层压板进行了建模,并与现有实验进行了比较。数值模型还用于模拟不同的层叠结构,以预测 LE 厚度对伪韧性拉伸行为和损伤模式演变的影响。正如文献中建议的那样,研究结果使我们能够描绘出所考虑的混合层压板的损伤模式图。该图区分了具有假韧性和脆性拉伸响应的全碳混合层压板配置。