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【新文速递】2024年5月5日复合材料SCI期刊最新文章

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今日更新:Composite Structures 1 篇,Composites Part A: Applied Science and Manufacturing 2 篇,Composites Part B: Engineering 14 篇,Composites Science and Technology 1 篇

Composite Structures

Analysis of raw-crushed wind-turbine blade as an overall concrete addition: Stress–strain and deflection performance effects

Vanesa Ortega-López, Flora Faleschini, Nerea Hurtado-Alonso, Javier Manso-Morato, Víctor Revilla-Cuesta

doi:10.1016/j.compstruct.2024.118170

风电叶片粗碎作为整体混凝土添加物分析:应力-应变和挠曲性能影响

End-of-life wind-turbine blades undergo non-selective crushing to produce Raw-Crushed Wind-Turbine Blade (RCWTB), which can be recycled as a raw material in concrete. RCWTB contains fibers from glass fiber-reinforced polymer that can add ductility and load-bearing capacity to concrete. Concrete mixes with percentage additions of between 0.0 % and 6.0 % RCWTB by volume are produced to analyze their compressive stress–strain performance, their deflection under bending forces, and their deformability under indirect-tensile stresses. Higher RCWTB contents increased deformability in the longitudinal direction under compression, the concrete material absorbing energy levels that were up to 111.4 % higher, even though additions of only 6.0 % RCWTB were sufficient to strengthen the load-bearing capacity. RCWTB fiber stitching effect was most noticeable in the transverse direction under compression, as it reduced elastic deformability and failure strain, removed the yield step caused by vertical-splitting cracking, and increased the fracture strain by up to 94.4 %. With regard to deflection, RCWTB fibers conditioned concrete compliance at advanced ages without any dependance on the modulus of elasticity, and percentage additions from 3.0 % provided load-bearing capacity. This advantage was also noted in indirect-tensile stresses for 6.0 % RCWTB. In summary, RCWTB successfully increased the ductility and load-bearing capacity of concrete per unit strength and carbon footprint.

使用寿命结束的风力涡轮机叶片经过非选择性破碎,生产出可作为混凝土原料回收利用的破碎风力涡轮机叶片(raw - crushed wind-turbine Blade, RCWTB)。RCWTB含有来自玻璃纤维增强聚合物的纤维,可以增加混凝土的延展性和承载能力。制备了体积掺量在0.0 % ~ 6.0 % RCWTB之间的混凝土配合比,分析了其压应力-应变性能、在弯曲力作用下的挠度以及在间接拉应力作用下的变形能力。较高的RCWTB含量增加了混凝土在纵向受压下的变形能力,即使仅添加6.0 % RCWTB就足以增强混凝土的承载能力,但混凝土材料的吸收能级最高可提高111.4 %。在压缩作用下,RCWTB纤维拼接效果在横向上最为显著,降低了材料的弹性变形能力和破坏应变,消除了垂直劈裂开裂导致的屈服步长,使断裂应变提高了94.4 %。关于挠度,RCWTB纤维在不依赖于弹性模量的情况下调节混凝土的后期顺应性,从3.0 %添加的百分比提供承载能力。在6.0 % RCWTB的间接拉伸应力中也注意到这一优势。综上所述,RCWTB成功地提高了混凝土的延性和单位强度的承载能力,减少了碳足迹。


Composites Part A: Applied Science and Manufacturing

Smart materials and Micro/Nano architectonics for water harvesting: From fundamental mechanism to advanced application

Xikui Wang, Han Wei, Ningkang Luo, Hong Luo, Xueqiu Zhou, Binli Qin, Yi Mei, Youfa Zhang

doi:10.1016/j.compositesa.2024.108241

集水智能材料和微纳米结构:从基本机制到高级应用

The shortage of water resources is a severe challenge that the world faces in the 21st century. By imitating the water harvesting behavior of organisms to obtain water from the atmosphere, it is a feasible way to alleviate the water crisis. The classical wetting theory of solid surfaces, the mechanisms of directional transportation of water droplets and bionic water harvesting principles of different bionic systems are summarized in this review, and the structural characteristics and water harvesting performance of different bionic systems are analyzed. Further, the paper classifies the smart water harvester systematically according to the different types and quantities of imitated organisms, and summarizes the water collection efficiency of different water harvesting methods. Then, this paper summarizes the application status of bionic water harvesting technology in agriculture, industry, and daily life, and prospects for the current shortcomings of smart water harvesting systems and future development trends.

水资源短缺是21世纪世界面临的严峻挑战。通过模仿生物的集水行为,从大气中获取水分,是缓解水危机的可行途径。综述了固体表面经典润湿理论、水滴定向输送机理和不同仿生系统的仿生集水原理,分析了不同仿生系统的结构特点和集水性能。进一步,根据模拟生物的种类和数量的不同,对智能集水器进行了系统的分类,总结了不同集水方式的集水效率。然后,总结了仿生集水技术在农业、工业和日常生活中的应用现状,并对智能集水系统目前存在的不足和未来发展趋势进行了展望。


Chemical compatibility between poly(ethylene) and cellulose nanofibers from kraft pulps containing varying amounts of lignin: An aqueous acetylation strategy and its effect on biocomposite properties

Nanci Ehman, Sandra Rodríguez-Fabià, Jennifer Zehner, Gary Chinga-Carrasco

doi:10.1016/j.compositesa.2024.108247

从含有不同数量木质素的硫酸盐纸浆中提取的聚乙烯和纤维素纳米纤维之间的化学相容性:水乙酰化策略及其对生物复合材料性能的影响

Previous efforts to acetylate fibers and cellulose nanofibers (CNFs) are methodologically demanding and usually based on organic solvents catalyzed by acids. Hence, the purpose of this study was to introduce an improved method to acetylate unbleached (2 % and 5 % lignin) and bleached fibers (<1% lignin), and the corresponding CNFs, using a one-pot strategy in an aqueous alkaline medium. The lignin content in the pulp fibers (5 %) influenced the morphology of the corresponding fibrillated materials, i.e., increased secondary fines (92 %) and mean fibril area (36 %). Additionally, the pulps and CNFs (0 % and 5 % lignin content) were acetylated and compounded with high-density poly(ethylene) (HDPE). Acetylation improved the mechanical strength from 19 MPa (HDPE) to 30–40 MPa (when including acetylated fibers or CNFs). Finally, acetylation revealed a positive effect on melt-flow-index and elongation at break, and the water absorption of injection molded specimens was reduced to roughly 0.6 % after 10 days of testing.

以前对纤维和纤维素纳米纤维(CNFs)乙酰化的研究在方法上要求很高,并且通常基于酸催化的有机溶剂。因此,本研究的目的是介绍一种改进的方法来乙酰化未漂白(2 %和5 %木质素)和漂白纤维(<1%木质素),以及相应的CNFs,使用一锅策略,在水性碱性介质中。纸浆纤维中木质素含量(5 %)影响了相应纤维化材料的形态,即增加了次生细纤维(92 %)和平均纤维面积(36 %)。此外,将纸浆和CNFs(木质素含量分别为0 %和5 %)乙酰化并与高密度聚乙烯(HDPE)复合。乙酰化使机械强度从19 MPa (HDPE)提高到30-40 MPa(包括乙酰化纤维或CNFs)。最后,乙酰化显示出对熔体流动指数和断裂伸长率的积极影响,并且在10 天的测试后,注射成型样品的吸水率降低到大约0.6 %。


Composites Part B: Engineering

Revealing the percolation-agglomeration transition in polymer nanocomposites via MD-informed continuum RVEs with elastoplastic interphases

Eva Maria Richter, Gunnar Possart, Paul Steinmann, Sebastian Pfaller, Maximilian Ries

doi:10.1016/j.compositesb.2024.111477

通过具有弹塑性界面相的md通知连续RVEs揭示聚合物纳米复合材料中的渗透-团聚转变

This contribution builds the concluding step of a multiscale approach to effectively capture the mechanical behavior of polymer nanocomposites (PNCs), in this case, silica-modified polystyrene. By introducing continuum-based representative volume elements (RVEs) that employ previously identified elastoplastic property gradients for the interphases surrounding the fillers, the effects of particle size, particle volume fraction, and agglomeration on the mechanical performance are investigated. Uniaxial tension tests are simulated with the respective finite-element RVEs, and stress–strain curves are derived. The elastic and plastic material properties of the RVE can then be extracted and analyzed quantitatively by fitting the stress–strain curves with a Voce-type elastoplasticity formulation.At small degrees of agglomeration, i.e., good particle dispersion, in combination with sufficiently large particle volume fraction, percolation bands form, leading to improved elastic and plastic properties. Higher degrees of agglomeration or particle clusters behave like large single particles, which has an adverse effect, i.e., the nanoscale size effect is thereby neutralized. Therefore, the precise MD-informed elastoplastic interphase representation of our RVEs enables the investigation of the transition from beneficial percolation to unfavorable agglomeration. Ultimately, this contribution establishes a link between the effects of particle size, particle volume fraction, agglomeration, and percolation, which have so far only been discussed separately in the literature.Our methodology offers new insights into the structure–property relations of PNCs and their resulting mechanical behavior. The underlying multiscale approach with a systematic transition from molecular to microscopic scales is required to complement experimental observations and exploit the full potential of PNCs.

这一贡献为有效捕获聚合物纳米复合材料(pnc)的力学行为的多尺度方法建立了最后一步,在这种情况下,是硅改性聚苯乙烯。通过引入基于连续体的代表性体积单元(RVEs),利用先前确定的填料周围界面的弹塑性性能梯度,研究了颗粒尺寸、颗粒体积分数和团聚对力学性能的影响。分别用有限元rve模拟了单轴拉伸试验,推导了应力-应变曲线。利用voce型弹塑性公式拟合应力-应变曲线,可提取并定量分析RVE材料的弹塑性性能。团聚度小,即颗粒分散性好,且颗粒体积分数足够大时,形成渗透带,弹塑性性能得到改善。更高程度的团聚或颗粒团簇表现得像大的单个颗粒,这有一个不利的影响,即,纳米级尺寸效应因此被中和。因此,我们的RVEs精确的md通知弹塑性间相表示可以研究从有益渗透到不利团聚的转变。最终,这一贡献建立了颗粒大小、颗粒体积分数、团聚和渗透的影响之间的联系,这些影响迄今为止只在文献中单独讨论过。我们的方法为pnc的结构-性能关系及其产生的力学行为提供了新的见解。需要从分子尺度到微观尺度的系统过渡的潜在多尺度方法来补充实验观察并充分利用pnc的潜力。


Development of a Novel Fractional Magneto-Viscoelastic Dynamic Model for an Adaptive Beam Featuring Functional Composite Magnetoactive Elastomers: Simulations and Experimental Studies

Seyed Alireza Moezi, Ramin Sedaghati, Subhash Rakheja

doi:10.1016/j.compositesb.2024.111501

功能复合磁活性弹性体自适应梁的新型分数阶磁粘弹性动力学模型的建立:仿真与实验研究

Recently, the rapid emergence of functional composite magnetoactive elastomers with integrated hard magnetic particles (known as hard magnetoactive elastomers) has attracted significant interest in fields such as soft robotics and material science. It is of paramount importance to develop an efficient model that can accurately predict the nonlinear dynamic behavior of adaptive structures for their practical application and the synthesis of effective control strategies. In this study, a novel nonlinear fractional magneto-viscoelastic model of an adaptive cantilevered beam featuring hard magnetoactive elastomers has been developed. This model effectively characterizes the beam’s nonlinear and rate-dependent response behavior under magnetic stimuli of varying frequencies and magnitudes. Considering the fractional Kelvin-Voigt energy dissipation model and large deformation nonlinearity, the governing equations for the cantilevered hard-magnetic soft beam were derived using the Hamilton principle. The finite difference method, combined with the Galerkin modal decomposition scheme, was subsequently utilized to discretize the time and space domains, respectively. A hardware-in-the-loop experimental framework was finally designed to experimentally investigate the beam’s nonlinear response behavior and validate the simulation results. The simulated nonlinear quasi-static responses of the beam, subjected to magnetic loading up to 30 mT, exhibited excellent agreement with the experimental data collected. Moreover, the simulated dynamic responses of the beam, subjected to various amplitudes of the applied magnetic field and magnetic frequencies up to 2 Hz, were thoroughly investigated. These included time-histories, phase-plane, and hysteretic responses, all demonstrating strong alignment with the experimental observations.

近年来,集成了硬磁颗粒的功能性复合磁活性弹性体(称为硬磁活性弹性体)的迅速出现引起了软机器人和材料科学等领域的极大兴趣。建立一种能够准确预测自适应结构非线性动力学行为的有效模型,对于自适应结构的实际应用和有效控制策略的综合具有重要意义。本文建立了一种新的含硬磁活性弹性体的自适应悬臂梁非线性分数阶磁粘弹性模型。该模型有效地表征了在不同频率和幅度的磁刺 激下梁的非线性和速率相关的响应行为。考虑分数阶Kelvin-Voigt能量耗散模型和大变形非线性,利用Hamilton原理推导了悬臂式硬磁软梁的控制方程。利用有限差分法,结合Galerkin模态分解格式,分别对时域和空域进行离散化。最后设计了半实物实验框架,对梁的非线性响应行为进行了实验研究,并对仿真结果进行了验证。在高达30mt的磁载荷下,模拟梁的非线性准静态响应与实验数据吻合良好。此外,还研究了在外加磁场的不同振幅和高达2 Hz的磁频率下,梁的模拟动态响应。这些包括时程、相平面和滞后响应,都显示出与实验观察的强烈一致性。


Repair of acrylic/glass composites by liquid resin injection and press moulding

Alp BOLLUK, Machar Devine, James A. Quinn, Dipa Ray

doi:10.1016/j.compositesb.2024.111513

丙烯酸/玻璃复合材料的液体树脂注射和压制成型修复

This paper presents repair methods for in-situ polymerised acrylic (Elium®)/glass composites focusing on mode-I fracture toughness recovery. Acrylic/glass composites were first subjected to double cantilever beam (DCB) tests to measure their Mode-I fracture toughness. The delaminated samples after DCB tests were repaired and rejoined. Two repair methods were performed: liquid resin injection and press moulding at two different temperatures (130°C and 160°C). The repaired samples were subjected to a second set of DCB tests. The fracture behaviours of the four specimen groups (virgin, resin-injected, pressed at 130°C, and pressed at 160°C) were evaluated in terms of strain energy release rates (GIC) during crack initiation and propagation. The results showed that specimens repaired by resin injection exhibited highest GIC values, about 30% higher than the virgin state, due to the formation of a semi-interpenetrating polymer network (semi-IPN) at the joining interface. Scanning electron microscopy images provided insight into distinctive fracture behaviours for each test group.

本文介绍了原位聚合丙烯酸(Elium®)/玻璃复合材料的修复方法,重点是i型断裂韧性恢复。首先对丙烯酸/玻璃复合材料进行双悬臂梁(DCB)试验,测量其i型断裂韧性。对DCB试验后的分层试样进行修复和重新连接。两种修复方法:液体树脂注射和在两种不同温度下(130°C和160°C)的压制成型。修复后的样品进行了第二组DCB测试。用应变能释放率(GIC)来评估四组试样(未加工、注射树脂、130℃和160℃)在裂纹起裂和扩展过程中的断裂行为。结果表明,由于在连接界面处形成了半互穿聚合物网络(半ipn),经树脂注射修复的样品具有最高的GIC值,比未修复状态高约30%。扫描电子显微镜图像提供了对每个试验组独特断裂行为的深入了解。


Numerical fatigue assessment of a cross-ply carbon fiber laminate using a probabilistic framework

Sara Eliasson, Gustav Hultgren, Per Wennhage, Zuheir Barsoum

doi:10.1016/j.compositesb.2024.111514

基于概率框架的交叉碳纤维层合板疲劳数值评估

A probabilistic framework is developed utilizing a two-scale modeling approach to efficiently consider the material variability that is typical for composite materials. The modeling integrates a macro-scale model with effective elastic properties extracted from micro-mechanical simulations. Using a weakest link modeling approach for fatigue assessment the combined effects of defects on fatigue strength in a Carbon Fiber Reinforced Polymer (CFRP) material can be investigated. A full fatigue test program is presented and is used to calibrate the probabilistic fatigue model. By including material variability in the numerical model, the calibrated probabilistic model improves the fatigue life prediction.

利用双尺度建模方法开发了一个概率框架,以有效地考虑典型复合材料的材料可变性。该模型将宏观尺度模型与从微观力学模拟中提取的有效弹性特性相结合。采用疲劳评估的最薄弱环节建模方法,可以研究碳纤维增强聚合物(CFRP)材料中缺陷对疲劳强度的综合影响。提出了一套完整的疲劳试验程序,并对概率疲劳模型进行了标定。校正后的概率模型通过在数值模型中加入材料的变异性,提高了疲劳寿命的预测精度。


Design of Hybrid Ag-Au Nanostructure based Fully Elastomeric Nanocomposite Electrodes for Soft Integrated Electronics

Seongsik Jeong, Hyeseon Jo, Donghyeon Seo, Hae-Jin Kim

doi:10.1016/j.compositesb.2024.111516

基于银金混合纳米结构的软集成电子全弹性纳米复合电极设计

Recent advancements in stretchable devices have opened new avenues for constructing soft electronics for use in applications such as health-monitoring wearables, advanced integrated circuits, and soft robotics. Meeting the increasing demand for enhanced functionality in soft electronics requires the development of soft conductors with high electrical conductivity, mechanical durability, and cost-effectiveness. Researchers have addressed this challenge by creating percolated networks within the elastomer as a nanocomposite using low-dimensional conducting nanomaterials to endow non-stretchable metallic materials with mechanical stretchability. For example, silver nanowires (AgNWs) have found wide application as essential fillers in soft conductor nanocomposites owing to their remarkable aspect ratio and cost-efficiency. However, their application is limited by their susceptibility to environmental degradation and poor compatibility with semiconducting materials. In this work, the hybrid Ag–Au based nanomaterials as a filler nanomaterial within an elastomer in a nanocomposite format was generated, as it exploits the strengths of each material while mitigating their respective weaknesses. Specifically, the work introduces the merit of the hybrid elastomeric electrodes that consist of AgNWs decorated with Au nanoparticles (AANWs), and Au nanosheets (AuNSs) embedded in a polydimethylsiloxane (PDMS) elastomer. These electrodes exhibit remarkable mechanical resilience and electrical conductivity, making them suitable for application in transistors, logic gates, integrated electronics, and soft displays. The work explores the synthesis and properties of hybrid materials comprising AgNWs and AuNSs, highlighting the promising potential of these materials for future research and development.

可伸缩设备的最新进展为构建用于健康监测可穿戴设备、先进集成电路和软机器人等应用的软电子设备开辟了新的途径。为了满足软电子领域对增强功能日益增长的需求,需要开发具有高导电性、机械耐用性和成本效益的软导体。研究人员已经解决了这一挑战,他们在弹性体中创建了渗透网络,作为一种纳米复合材料,使用低维导电纳米材料赋予不可拉伸的金属材料具有机械拉伸性。例如,银纳米线(AgNWs)由于其显著的长径比和成本效益而被广泛应用于软导体纳米复合材料中。然而,它们的应用受到环境退化的敏感性和与半导体材料的兼容性差的限制。在这项工作中,以纳米复合材料的形式生成了作为弹性体填充纳米材料的Ag-Au基杂化纳米材料,因为它利用了每种材料的优点,同时减轻了它们各自的缺点。具体来说,该工作介绍了混合弹性体电极的优点,该电极由镀有金纳米粒子(AANWs)的AgNWs和嵌在聚二甲基硅氧烷(PDMS)弹性体中的金纳米片(AuNSs)组成。这些电极表现出卓越的机械弹性和导电性,使其适用于晶体管,逻辑门,集成电子和软显示。这项工作探讨了由AgNWs和aass组成的混合材料的合成和性能,强调了这些材料在未来研究和开发中的巨大潜力。


La-doped Sr4Fe4Co2O13-δ as a promising in-situ self-assembled composite cathode for protonic ceramic fuel cells

Yuxuan Li, Yang Li, Shanshan Jiang, Yubo Chen, Jiahuan Xu, Hao Qiu, Chao Su, Lei Ge

doi:10.1016/j.compositesb.2024.111517

 

la掺杂Sr4Fe4Co2O13-δ作为质子陶瓷燃料电池原位自组装的复合阴极

Protonic ceramic fuel cells (PCFCs) exhibit a lower activation energy compared to conventional oxygen-ion conducting solid oxide fuel cells, which makes them better suited for operating at low temperatures. Regrettably, the use of PCFCs at lower temperatures is restricted due to the absence of durable and highly active cathode materials. Herein, we rationally design in-situ self-assembled composite cathodes with the nominal compositions of Sr4-xLaxFe4Co2O13-δ (SLxFC, x = 0.4, 0.8, 1, and 2) for PCFCs. The SL0.4FC, displays a composite of cubic perovskite phase and spinel phase, the other compositions yield a mixture of both orthorhombic perovskite and spinel phases. The self-assembled SL1FC composite cathode has the highest electrocatalytic activity among all samples, particularly at temperatures (< 650 oC). For instance, it demonstrates a very low area-specific resistance (ASR) of 0.465 Ω cm2 at 550 oC. The PCFC with the SL1FC composite cathode provides a high peak power density (PPD) of 518 mW cm-2 at the same temperature. More importantly, the SL1FC electrode demonstrates robust long-term stability (400 h for the symmetrical cell mode and 200 h for the single cell mode). This study shows how La doping enhances the electrochemical activity of Sr4Fe4Co2O13-δ and how the synergistic effect of the two phases boosts the electrochemical performance of the composite cathode.

与传统的氧离子导电固体氧化物燃料电池相比,质子陶瓷燃料电池(pcfc)具有更低的活化能,这使得它们更适合在低温下工作。遗憾的是,由于缺乏耐用和高活性的阴极材料,pcfc在较低温度下的使用受到限制。为此,我们合理设计了Sr4-xLaxFe4Co2O13-δ (SLxFC, x = 0.4, 0.8, 1和2)的原位自组装复合阴极。SL0.4FC为立方钙钛矿相和尖晶石相的复合材料,其他成分为正交钙钛矿相和尖晶石相的混合物。自组装的SL1FC复合阴极在所有样品中具有最高的电催化活性,特别是在< 650℃的温度下。例如,在550℃时,它的面积比电阻(ASR)非常低,为0.465 Ω cm2。具有SL1FC复合阴极的PCFC在相同温度下提供518 mW cm-2的峰值功率密度(PPD)。更重要的是,SL1FC电极表现出强大的长期稳定性(对称电池模式为400小时,单电池模式为200小时)。本研究揭示了La掺杂如何增强Sr4Fe4Co2O13-δ的电化学活性,以及两相的协同作用如何提高复合阴极的电化学性能。


A Shape-Performance Synergistic Strategy for Design and Additive Manufacturing of Continuous Fiber Reinforced Transfemoral Prosthetic Socket

Changning Sun, Lei Tang, Tengda Liu, Ling Wang, Xiaoyong Tian, Chaozong Liu, Dichen Li

doi:10.1016/j.compositesb.2024.111518

连续纤维增强经股骨假体窝设计与增材制造的形状-性能协同策略

A shape-performance synergistic design and additive manufacturing strategy was developed for the transfemoral prosthetic sockets (TPS) to fulfill the demands of customized geometry and long-term load bearing. The 3D printing path of the continuous fiber reinforced polymer composites (CFRPC) was generated by reversing the milling path of subtractive manufacturing. The mechanical properties of the 3D printed CFRPC samples were investigated as a foundation, and the customized fiber trajectories were designed based on the analyzed stress pattern of the TPS in daily gait. The CFRPC TPS with weight of 28% less than those made by pure resin had a safety factor larger than 3 and passed the fatigue testing of 3 million cycles. The design and additive manufacturing strategy developed in this study was also applicable for other parts with freeform surfaces.

采用形状-性能协同设计和增材制造策略,开发了经股骨假体(TPS),以满足定制几何形状和长期承载的需求。将减法加工的铣削路径反向生成连续纤维增强聚合物复合材料(CFRPC)的3D打印路径。以3D打印CFRPC样品的力学性能为基础,根据分析的TPS在日常步态中的应力模式,设计定制纤维轨迹。与纯树脂相比,重量减轻28%的CFRPC TPS的安全系数大于3,通过了300万次的疲劳试验。本研究开发的设计和增材制造策略也适用于其他具有自由曲面的零件。


Enhancing strength-ductility properties of immiscible W–Cu composite by creating low-energy phase interfaces

Yurong Li, Jianfei Zhang, Chao Hou, Hao Lu, Haibin Wang, Xuemei Liu, Shengcheng Mao, Xinping Zhang, Yinong Liu, Xiaoyan Song

doi:10.1016/j.compositesb.2024.111520

 

通过建立低能相界面提高非混相W-Cu复合材料的强度-延展性

The immiscible bimetallic composites play an important role in civilian industries and aerospace fields owing to their integrated mechanical and physical properties. However, metallic composites of immiscible constituents suffer from one critical drawback of weak interface bonding, which makes the composites particularly vulnerable at elevated service temperatures. Here we proposed a novel strategy to resolve the challenge by creating low-energy phase interfaces in a typical immiscible bimetallic W–Cu composite. This was achieved by in-situ reactions of WO3 and CuO with WC, which acts in a dual function as the reducing agent for the reactions and an interface forming agent. The sintered W-WC-Cu composite possessed a significant number of low-energy WC/W and WC/Cu interfaces and exhibited a compressive strength of 609 MPa and a compressive ductility of 22.6 % at 600 °C, which ranks among the highest in similar composites. The characteristics of WC/W and WC/Cu interfaces and their effects on the mechanical behavior of the composite were demonstrated by the timely and atomic-resolved high-temperature mechanical investigations. The introduced stable interfaces were also found to induce [1‾11]BCC → [011]FCC phase transformation of W as another mechanism of plastic deformation in addition to dislocation activities in W and Cu. This study provides a new approach to greatly enhance the mechanical properties of the immiscible metallic composites.

不相溶双金属复合材料因其综合机械和物理特性,在民用工业和航空航天领域发挥着重要作用。然而,不相溶成分的金属复合材料存在界面结合力弱这一关键缺陷,这使得复合材料在高温条件下特别脆弱。在此,我们提出了一种新策略,通过在典型的不相溶双金属 W-Cu 复合材料中创建低能相界面来解决这一难题。这是通过 WO3 和 CuO 与 WC 的原位反应实现的,WC 具有反应还原剂和界面形成剂的双重功能。烧结的 W-WC-Cu 复合材料具有大量的低能 WC/W 和 WC/Cu 界面,在 600 °C 时的抗压强度为 609 兆帕,抗压延展性为 22.6%,在同类复合材料中名列前茅。及时的原子分辨高温力学研究证明了 WC/W 和 WC/Cu 界面的特性及其对复合材料力学行为的影响。研究还发现,除了 W 和 Cu 中的位错活动外,引入的稳定界面还能诱导 W 的 [1‾11]BCC → [011]FCC 相变,这是另一种塑性变形机制。这项研究为大大提高不相溶金属复合材料的机械性能提供了一种新方法。


Prodrug-inspired therapeutics: albuminized ceria nanozymes for osteoarthritis treatment

Li Zhou, Weikun Meng, Yilin Wang, Peifang Li, Jiali Chen, Yu Zeng, Weinan Zeng

doi:10.1016/j.compositesb.2024.111521

前药物启发疗法:白化铈纳米酶治疗骨关节炎

Osteoarthritis (OA) represents a highly prevalent degenerative joint disorder primarily driven by chronic inflammation and oxidative stress within the hypoxic microenvironment. Although the oral prodrug sulindac (SUL) is commonly used to manage OA, its therapeutic efficacy must rely on in vivo reduction into its active form, sulindac sulfide (SSUL), to mitigate inflammation. Inspired by "repurposing old drugs" and leveraging the redox properties of nanoceria, we developed albuminized ceria nanozymes loaded with SUL (BSA-SSUL-Ce) via self-assembly, where the valence state transformation drives SUL to SSUL. Notably, BSA-SSUL-Ce was selectively internalized by inflammatory macrophages, enabling precise delivery to inflammatory sites. Compared with prodrug SUL, the SOD enzymatic properties of BSA-SSUL-Ce conferred themselves with reducibility, facilitating attenuation of inflammatory signals by SSUL. Following, these nanocomposites exerted catalase activity, scavenging reactive oxygen species in situ and converting them into oxygen, thereby inhibiting hypoxia-inducible factor-1α. In a rat model of chronic OA, intra-articular injection of BSA-SSUL-Ce achieved synergistic therapeutic effects and good biocompatibility. Moreover, the preventive effect of BSA-SSUL-Ce in acute liver injury inflammatory models further expands its potential scenarios. This platform represents a promising therapeutic and preventive candidate for treating acute and chronic inflammatory diseases.

骨关节炎(OA)是一种非常普遍的退行性关节疾病,主要由缺氧微环境中的慢性炎症和氧化应激引起。虽然口服前药sulindac (SUL)通常用于治疗OA,但其治疗效果必须依赖于体内还原为活性形式sulindac sulfide (SSUL)来减轻炎症。受“旧药物再利用”的启发,利用纳米铈的氧化还原特性,我们通过自组装开发了装载SUL (bsa - SUL- ce)的白蛋白化二氧化铈纳米酶,其中价态转化驱动SUL到SSUL。值得注意的是,bsa - sull - ce被炎症巨噬细胞选择性内化,能够精确递送到炎症部位。与前药SUL相比,bsa - SUL- ce的SOD酶特性使其具有还原性,有利于SSUL对炎症信号的衰减。随后,这些纳米复合材料发挥过氧化氢酶活性,就地清除活性氧并将其转化为氧气,从而抑制缺氧诱导因子-1α。在慢性OA大鼠模型中,关节内注射bsa - sull - ce具有协同治疗作用和良好的生物相容性。此外,bsa - sull - ce对急性肝损伤炎症模型的预防作用进一步扩大了其潜在的应用前景。该平台代表了治疗急慢性炎症性疾病的有希望的治疗和预防候选。


Additively manufactured low-gradient interfacial heterostructured medium-entropy alloy multilayers with superior strength and ductility synergy

Yonggang Sun, Changjiang Zhang, Zhiliang Ning, Jianfei Sun, Alfonso H.W. Ngan, Yongjiang Huang

doi:10.1016/j.compositesb.2024.111522

 

增材制造低梯度界面异质中熵合金多层膜,具有优异的强度和延性协同作用

Metallic additive manufacturing (AM) offers near net-shape fabrication but often results in insufficient strength and/or ductility due to voids or cracks, coarse initial crystalline microstructure, insufficient volume fraction of precipitates and yet post-AM strengthening/toughening methods non-destructive to shape are generally lacking. Here, we report a laser-directed energy deposited (L-DED) medium entropy alloy (MEA) with a heterostructure (HS) comprising alternate layers of solid-solution and intermetallic-dispersed MEA that possess ultimate tensile strength of 1132.8 MPa and elongation of 50.6%, corresponding to strength-ductility synergy higher than other medium- or high-entropy alloys reported. The multilayers were produced from a dual source of CoCrNi MEA powder and a powder mixture of the same MEA, Al and Ti with stoichiometry (CoCrNi)86Al7Ti7, and the remarkable strength-ductility synergy is achieved only after post-L-DED heat treatment, which causes Al and Ti to diffuse across the layers to form a low-gradient HS. The significant back stress due to the HS contributes to the high strength, while the high ductility results from a high strain-hardening rate suppressing necking. This study demonstrates the concept of using AM not just as a near net-shape fabrication method but also a unique tool to produce low-gradient HSs with superb mechanical properties, via the use of multiple powder sources combined with suitable shape-preserving post-fabrication heat treatment.

金属增材制造(AM)提供了接近净形状的制造,但由于空洞或裂纹、粗糙的初始晶体微观结构、沉淀的体积分数不足,通常会导致强度和/或延展性不足,而且通常缺乏对形状无损的增材制造后强化/增韧方法。本文报道了一种由固溶体和金属间分散的异质结构(HS)组成的激光定向能沉积(L-DED)中熵合金(MEA),其极限抗拉强度为1132.8 MPa,伸长率为50.6%,其强度-延性协同效应高于其他中熵或高熵合金。采用CoCrNi MEA粉末和CoCrNi 86Al7Ti7混合的MEA、Al和Ti粉末制备多层材料,经过l - ded热处理后,Al和Ti在层间扩散形成低梯度HS,形成了显著的强度-塑性协同效应。高强度源于高背应力,而高塑性源于高应变硬化率抑制颈缩。这项研究证明了增材制造不仅是一种接近净形状的制造方法,而且是一种独特的工具,通过使用多种粉末源结合适当的保持形状的加工后热处理,可以生产具有优异机械性能的低梯度高速钢。


Synthesis of novel Stachytarpheta jamaicensis flower liked hexagonal boron nitride nanoribbons (SJF-BNNBs) to efficiently improve the thermal/mechanical/electrical properties of flexible polyimide films

Jilin Wang, Wenzhuo Chen, Yuchun Ji, Yuanlie Yu, Yuetong Wu, Jialong Shen, Huasong Liang, Guoyuan Zheng, Huanping Zhou, Fei Long

doi:10.1016/j.compositesb.2024.111524

新型水杨花状六方氮化硼纳米带(sjf - bnnb)的合成以有效改善柔性聚酰亚胺薄膜的热/力学/电学性能

Heat dissipation has become a bottleneck restricting large-scale integration and flexible electronic technologies. This study reports a novel fabrication strategy to prepare flexible stachytarpheta jamaicensis flower-like hexagonal boron nitride nanoribbons (SJF-BNNBs) and their composite films with polyimide (PI). The effect of synthesis conditions on the morphology of SJF-BNNBs was investigated, and the growth mechanism was proposed. The in-plane and through plane thermal conductivities of the 4 wt% SJF-BNNBs/PI composite film reach 5.98 W m−1 K−1 and 0.79 W m−1 K−1, which are 3047 % and 316 % higher than those of the pure PI film, respectively. The in-plane and through plane thermal conduction enhancement efficiencies reach 761.8 % and 78.9 %, respectively. The tensile strength of the composite film is 61.7 % higher than that of pure PI, and maintains excellent electrical insulating and thermal stability properties. Infrared imaging tests verified the excellent heat dissipation performance of the composite film as a thermal interface material and a flexible copper clad laminate substrate, where the operating temperature of device could be reduced by 17.3 °C. To the best of our knowledge, SJF-BNNBs outperform the most efficient thermally conductive electrically insulating filler and are to break the overcome of polymer composites in heat dissipation applications.

散热已经成为制约大规模集成和柔性电子技术发展的瓶颈。本文报道了一种新的制备方法,用于制备柔性牙买加水芋花状六方氮化硼纳米带(sjf - bnnb)及其与聚酰亚胺(PI)的复合薄膜。研究了合成条件对sjf - bnnb形貌的影响,并提出了其生长机理。4 wt% sjf - bnnb /PI复合膜的面内热导率为5.98 W m−1 K−1,通面热导率为0.79 W m−1 K−1,分别比纯PI膜高3047%和316%。面内和通面热传导增强效率分别达到761.8%和78.9%。复合膜的抗拉强度比纯PI高61.7%,并保持了良好的电绝缘性和热稳定性。红外成像测试验证了复合薄膜作为热界面材料和柔性覆铜层压板基板具有优异的散热性能,器件工作温度可降低17.3℃。据我们所知,sjf - bnnb优于最有效的导热绝缘填料,并将打破聚合物复合材料在散热应用中的克服。


Effect of polymer infiltration and pyrolysis (PIP) on microstructure and properties of high volume fraction SiC/Al composites prepared by a novel hybrid additive manufacturing

Guizhou Liu, Shixiang Zhou, Shuang Chen, Ruiying Luo, Yue Zhang, Changshun Wang, Qingchun Yang, Chunze Yan, Yusheng Shi

doi:10.1016/j.compositesb.2024.111525

聚合物浸润热解(PIP)对复合材料微观结构和性能的影响

High-volume-fraction SiC/Al (HVF-SiC/Al) composites have a wide range of applications in aerospace, optics, automotive and electronic packaging. However, because the hardness, brittleness and wear resistance increase with the increase in the volume fraction, it is difficult for traditional methods such as machining, to process HVF-SiC/Al composites to complex components. Therefore, in this paper, a novel method of the hybrid additive manufacturing is proposed to fabricate complex-structures SiC/Al composite parts. The effect of polymer infiltration and pyrolysis (PIP) on microstructure and properties of HVF-SiC/Al composites is investigated. The results show that the mechanical properties of the SiC preforms can be effctively enhanced by the PIP process, and this enhancement makes the SiC preforms meet the conditions for subsequent vacuum-pressure infiltration. The mechanical property of HVF-SiC/Al composites show a huge increase when in creasing the volume fraction of SiC. In particular, the flexural strength of HVF-SiC/Al composites increased from 202.28 MPa to 380.87 MPa, and the coefficient of thermal expansion (CTE) has also been reduced from 11.80 to 6.28 × 10-6/K, when the volume fraction of SiC increases from 42 to 80 vol%. For optimise the PIP process in the future, three theoretical models are used to predict the relationship between the CTE and the volume fraction of SiC. The results show that the experimental data are more consistent with the predicted values based on the Kerner’s model, but deviate from the Rule-of-mixture (ROM) and Turner’s models. Importantly, the complex-structures SiC/Al composite parts was successfully fabricated by this hybrid additive manufacturing.

高体积分数SiC/Al (HVF-SiC/Al)复合材料在航空航天、光学、汽车和电子封装等领域有着广泛的应用。然而,由于HVF-SiC/Al复合材料的硬度、脆性和耐磨性随体积分数的增加而增加,传统的机械加工等方法难以将其加工成复杂的部件。为此,本文提出了一种复合增材制造复杂结构SiC/Al复合材料零件的新方法。研究了聚合物浸润热解(PIP)对HVF-SiC/Al复合材料微观结构和性能的影响。结果表明:PIP工艺能有效提高SiC预制体的力学性能,使其满足后续真空压渗的条件;随着SiC体积分数的增加,HVF-SiC/Al复合材料的力学性能显著提高。当SiC的体积分数从42 %增加到80 %时,HVF-SiC/Al复合材料的抗弯强度从202.28 MPa提高到380.87 MPa,热膨胀系数(CTE)从11.80降低到6.28 × 10-6/K。为了优化未来的PIP工艺,采用了三个理论模型来预测CTE与SiC体积分数的关系。结果表明,实验数据与基于Kerner模型的预测值较为吻合,但与混合规则(Rule-of-mixture, ROM)和Turner模型存在偏差。重要的是,这种混合增材制造技术成功地制造了复杂结构的SiC/Al复合材料零件。


A Novel Microwave Assisted Multi-Material 3D Printing Strategy to Architect Lamellar Piezoelectric Generators for Intelligent Sensing

Haoran Pei, Yinghong Chen, Qinniu Lv, Zilin Peng, Xin Wang, Ning Chen, Huarong Zhang

doi:10.1016/j.compositesb.2024.111529

 

一种新的微波辅助多材料3D打印策略构建用于智能传感的片层压电发生器

While the advances in thermoplastic additive manufacturing (3D printing) cover the free-form fabrication of piezoelectric materials, the chief obstacles to the use of 3D printed piezoelectric generator (PEG) are the weak weld within the part and imperfect polarization. Herein, a microwave assisted multi-material 3D printing strategy is proposed to fabricate multiple PEGs consisting of periodically intercalated piezoelectric & conductive layers. The interfacial regulation performed between piezoelectric ceramics and matrix leads to sufficient polarization under the electric field, thus generating the substantially enhanced piezoelectricity. Benefiting from the unique design of embedded electrode with 3D graphene nanoplatelets (GNPs) network, the polarization charge density greatly increases. Then the microwave irradiation technology is employed to realize the intense selective heating of the GNPs to weld polymer interfaces, further improving the piezoelectric output. As a result, the output current of the 3D lamellar PEG is nearly 18 times higher than that of conventional sandwich structure PEG. With significant advantages of the enhanced electromechanical coupling performance, the fabrication strategy is expected to create multifunctional sensors with complex geometries. Based on the above method, the 3D printed biomimetic lamellar denture is developed for health monitoring and Morse code transmission, demonstrating its enormous potential in real-life applications.

虽然热塑性增材制造(3D打印)的进步涵盖了压电材料的自由形状制造,但使用3D打印压电发生器(PEG)的主要障碍是部件内部的弱焊接和不完美的极化。本文提出了一种微波辅助多材料3D打印策略,用于制造由周期性嵌入的压电层和导电层组成的多层聚乙二醇。压电陶瓷与基体之间的界面调节导致电场作用下产生足够的极化,从而产生大幅度增强的压电性。得益于三维石墨烯纳米片(GNPs)网络嵌入电极的独特设计,极化电荷密度大大提高。然后利用微波辐照技术实现GNPs的强选择性加热,焊接聚合物界面,进一步提高压电输出。结果表明,三维层状聚乙二醇的输出电流是传统夹层结构聚乙二醇的近18倍。该制造策略具有机电耦合性能增强的显著优势,有望制造出具有复杂几何形状的多功能传感器。基于上述方法,开发了用于健康监测和莫尔斯电码传输的3D打印仿生板层义齿,显示了其在现实应用中的巨大潜力。


Carbon nanotube-induced localized laser heating toward simultaneously enhanced laydown efficiency and fracture toughness of in-situ consolidated glass fiber thermoplastic composites

Wei Jiang, Cheng Chen, Xukang Wang, Huang Gao, Maoyuan Li, Zhigao Huang, Huamin Zhou

doi:10.1016/j.compositesb.2024.111531

 

碳纳米管诱导的局部激光加热可同时提高原位固结玻璃纤维热塑性复合材料的铺设效率和断裂韧性

Thermoplastic composites suffer from weak inter-tape bonding during high-rate laser-assisted automated fiber placement (L-AFP). Here, we propose a strategy to simultaneously enhance the laser heating efficiency and fracture toughness of glass fiber-reinforced polypropylene prepreg tape for L-AFP process by depositing carbon nanotubes (CNTs) on the tape surface by a low-cost bath coating process. CNTs function as efficient light absorbing and photothermal coating to promote molecular inter-diffusion and interfacial healing between successive tapes, as well as toughen the weak interface by CNT pull-out and rupture. A 56% increase in the near-infrared laser absorption of tapes results in a 946% improvement in the laydown rate. CNTs also remarkably improve transverse temperature uniformity. Furthermore, double cantilever beam and pants tearing tests show that 0.5 wt.% CNTs improve the mode I interlaminar fracture toughness and mode III fracture strength by 17% and 52%, respectively, attributed to the enhanced molecular inter-diffusion and CNT bridging effect.

热塑性复合材料在高速激光辅助自动光纤铺放(L-AFP)过程中存在带间粘接弱的问题。本研究提出了一种低成本镀膜工艺,通过在L-AFP工艺玻璃纤维增强聚丙烯预浸料带表面沉积碳纳米管(CNTs),同时提高激光加热效率和断裂韧性的策略。碳纳米管作为有效的光吸收和光热涂层,促进分子间的相互扩散和连续带之间的界面愈合,并通过碳纳米管的拔出和断裂使弱界面变韧。胶带近红外激光吸收率提高56%,铺层率提高946%。CNTs还显著改善了横向温度均匀性。此外,双悬臂梁和裤子撕裂试验表明,0.5 wt.% CNTs增强了分子间扩散和碳纳米管桥接效应,使I型层间断裂韧性和III型断裂强度分别提高了17%和52%。


Composites Science and Technology

Research on foldable two-matrix 3D braided composites: Manufacturing and bending progressive damage

Tianrui Li, Xiyan Du, Dong Zhou, Yiqi Mao, Ran Tao, Daining Fang

doi:10.1016/j.compscitech.2024.110637

 

可折叠双基体三维编织复合材料的研究:制造与弯曲渐进损伤

Three-dimensional braided composites have the potential to enhance the performance of composite hinges due to their high interlaminar strength, structural integrity, and damage tolerance. In this study, we first developed a multimatrix subdomain composite technique for fabric composites with 3D structural fabrics to fabricate multimatrix 3D braided composites. On the basis of this fabrication method, we designed a foldable 3D braided composite material using the rigid–flexible domain design method commonly used in flexible metamaterials. Experimental studies demonstrated that the material had ultrahigh rigid–flexible region connection strength and high rigid-region load-bearing capacity. It also had a reproducible, hermetically sealed large deformation capacity and required only a small amount of external force action and energy consumption. In addition, we revealed the progressive damage mechanism of foldable 3D braided composites during large deformations in bending, which guided the design of the flexible metamaterials.

三维编织复合材料由于具有较高的层间强度、结构完整性和损伤容忍度,具有提高复合铰链性能的潜力。在本研究中,我们首先开发了一种基于三维结构织物复合材料的多矩阵子域复合技术,以制备多矩阵三维编织复合材料。在此基础上,采用柔性超材料中常用的刚柔域设计方法,设计了一种可折叠的三维编织复合材料。试验研究表明,该材料具有超高的刚柔区连接强度和较高的刚性区承载能力。它还具有可重复的、密封的大变形能力,只需要很小的外力作用和能量消耗。此外,揭示了可折叠三维编织复合材料在弯曲大变形过程中的递进损伤机理,为柔性超材料的设计提供了指导。



来源:复合材料力学仿真Composites FEM
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首次发布时间:2024-11-14
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【新文速递】2024年5月7日复合材料SCI期刊最新文章

今日更新:Composite Structures 2 篇,Composites Part A: Applied Science and Manufacturing 1 篇,Composites Part B: Engineering 1 篇,Composites Science and Technology 1 篇Composite StructuresEffects of long-term exposure of NSM CFRP-to-concrete bond to natural and accelerated aging environmentsAloys Dushimimana, José Sena-Cruz, Luís Correia, João Miguel Pereira, Susana Cabral-Fonseca, Ricardo Cruzdoi:10.1016/j.compstruct.2024.118174NSM cfrp -混凝土粘结剂长期暴露于自然和加速老化环境中的影响Carbon fiber reinforced polymer (CFRP) composites can be used to strengthen existing reinforced concrete (RC) structures. The CFRP laminate can be bonded to RC structure using epoxy adhesive via near-surface mounted (NSM) strengthening technique. However, existing literature generally lacks data about durability of NSM CFRP-to-concrete bond. In this study, strengthened concrete elements were exposed to laboratory-controlled environments (at approximately 20 °C/55 % RH, and water immersion at 20 °C) and natural field environments (to promote natural aging induced mainly by carbonation, high temperatures, freeze–thaw attack, and airborne chlorides) for up to four years. Durability tests were conducted yearly for the bond and its constituent materials. The highest bond strength degradations were nearly 12 % and 9 % for the specimens immersed in water and those exposed to freeze–thaw attack, respectively. Besides, environmental conversion factors of 0.88 and 0.93 were derived from a database of existing accelerated, and natural aging data from the present work, respectively.碳纤维增强聚合物(CFRP)复合材料可用于加固现有的钢筋混凝土(RC)结构。采用近表面安装(NSM)加固技术,采用环氧胶粘剂将CFRP复合材料粘接在RC结构上。然而,现有文献普遍缺乏关于NSM cfrp -混凝土粘结耐久性的数据。在这项研究中,加固混凝土元件暴露在实验室控制的环境(大约20 °C/55 % RH, 20 °C的水浸泡)和自然现场环境(促进主要由碳化、高温、冻融侵蚀和空气中的氯化物引起的自然老化)中长达四年。每年对粘结剂及其组成材料进行耐久性试验。浸水和冻融作用下的粘结强度下降幅度最大,分别接近12 %和9 %。环境转换因子分别为0.88和0.93,分别来自现有加速老化和自然老化数据库。High fidelity FEM based on deep learning for arbitrary composite material structureJiaxi Li, Weian Yao, Yu Lu, Jianqiang Chen, Yan Sun, Xiaofei Hudoi:10.1016/j.compstruct.2024.118176基于深度学习的任意复合材料结构高保真有限元分析Due to the outstanding performance, composite materials are widely used and analyzing their properties and designing them based on performance has become a crucial task in the field of many manufacturing industries. Composite materials possess complex multiscale structures, and traditional fine-scale finite element modeling and analysis may lead to severe computational resource challenges. To overcome this difficulty, breakthroughs in key technologies of multiscale accelerated analysis algorithms are required. In this study, an innovative approach based on artificial intelligence and multiscale finite element method is presented. This approach involves partitioning the entire composite material structure into coarse grids that resemble homogenous structures of similar size, providing results consistent to fine-grid finite element analysis. By utilizing CNN for image feature recognition and employing the CGAN adversarial method, coarse-grid equivalent stiffness matrices and multiscale shape functions from completely random microstructures of composite materials can be obtained. Consequently, this enables a rapid response process from microstructure to low-resolution grid to high-resolution physical field, with remarkably accurate physical field results. Moreover, compared to traditional fine-grid finite element methods, this approach significantly reduces memory usage and computation time. This method is applicable to composite materials with varying shaped inclusions, different component properties, and diverse geometric distributions, allowing these materials to perform high-fidelity finite element calculations on coarse grids and predict their mechanical behavior. Furthermore, this breakthrough opens avenues for accelerating the optimization design of composite materials with diverse mechanical functionalities, by employing a bottom-up approach.复合材料由于其优异的性能得到了广泛的应用,分析其性能并根据其性能进行设计已成为许多制造业领域的一项重要任务。复合材料具有复杂的多尺度结构,传统的精细尺度有限元建模和分析对计算资源构成了严峻的挑战。为了克服这一困难,需要突破多尺度加速分析算法的关键技术。本研究提出了一种基于人工智能和多尺度有限元方法的创新方法。这种方法包括将整个复合材料结构划分为粗网格,这些粗网格类似于大小相似的同质结构,从而提供与细网格有限元分析一致的结果。利用CNN进行图像特征识别,采用CGAN对抗方法,可以得到复合材料完全随机微观结构的粗网格等效刚度矩阵和多尺度形状函数。因此,这使得从微观结构到低分辨率网格再到高分辨率物理场的快速响应过程成为可能,并且具有非常精确的物理场结果。此外,与传统的细网格有限元方法相比,该方法显著减少了内存使用和计算时间。该方法适用于具有不同形状夹杂物、不同组分性能和不同几何分布的复合材料,允许这些材料在粗网格上进行高保真的有限元计算,并预测其力学行为。此外,通过采用自下而上的方法,这一突破为加速具有多种机械功能的复合材料的优化设计开辟了道路。Composites Part A: Applied Science and ManufacturingAn efficient finite element mesh generation methodology based on μCT images of multi-layer woven compositesXuanxin Tian, Heng Zhang, Zhaoliang Qu, Shigang Aidoi:10.1016/j.compositesa.2024.108255 基于多层编织复合材料μCT图像的高效有限元网格生成方法High-fidelity models are essential for accurate finite element (FE) simulations of composite material behavior. This paper proposes an efficient meshing methodology based on micro-Computed Tomography (μCT) images. U-Net convolutional neural network was used for image segmentation. Connected yarns were then separated using an improved procedure based on watershed algorithm and geometric transformations. The proposed Constrained Delaunay-Advancing Front Technique (CD-AFT) surface reconstruction algorithm extracts point cloud of yarns from segmented images and outputs high-quality and smooth orientable manifold watertight triangulated surface. Intersecting meshes of yarns are separated through node position detection and Laplacian moving. Experimental results show that proposed methodology is capable of accomplishing mesh generation for different mesh sizes. Compared with commercial software, it has obvious advantages in mesh quality and size control. Since the proposed method operates independently of commercial software and manual operation, it facilitates the automated generation of numerous high-fidelity models from μCT images for FE simulations.高保真模型对于复合材料性能的精确有限元模拟至关重要。提出了一种基于微计算机断层扫描(μCT)图像的高效网格划分方法。采用U-Net卷积神经网络进行图像分割。然后使用基于分水岭算法和几何变换的改进方法分离连接的纱线。提出的约束delaunay推进前沿技术(CD-AFT)曲面重建算法从分割图像中提取纱线点云,输出高质量、光滑的可定向流形水密三角曲面。通过节点位置检测和拉普拉斯移动分离纱线的相交网格。实验结果表明,该方法能够实现不同网格尺寸的网格生成。与商业软件相比,它在网格质量和尺寸控制方面具有明显的优势。由于该方法独立于商业软件和人工操作,它有助于从μCT图像中自动生成大量高保真模型用于FE模拟。Composites Part B: EngineeringIntegrated Accelerated Testing Methodology for CFRP DurabilityYasushi Miyano, Masayuki Nakadadoi:10.1016/j.compositesb.2024.111527CFRP耐久性综合加速试验方法Integrated ATM, an integrated accelerated testing methodology for CFRP durability, is described herein. It is expressed as a single formula including several parameters representing the life of CFRP under an arbitrary environmental temperature and an arbitrary strain ratio R from R =0 to 1. Integrated ATM is based on Christensen&#39;s viscoelastic crack kinetics and conventional ATM. First, Integrated ATM is introduced based on the matrix resin viscoelasticity. Second, important parameters which affect CFRP life are found for the longitudinal tensile strength of a unidirectional CFRP as an Integrated ATM application. Finally, the parameter influences on CFRP life are assessed.本文描述了集成ATM,一种CFRP耐久性的集成加速测试方法。在任意环境温度下,在R =0 ~ 1的任意应变比R下,CFRP的寿命可表示为包含多个参数的单一公式。综合自动取款机是基于克里斯坦森粘弹性裂纹动力学和传统自动取款机。首先,介绍了基于基体树脂粘弹性的集成ATM。其次,找到了影响碳纤维增强材料寿命的重要参数,用于单向碳纤维增强材料的纵向拉伸强度作为集成ATM应用。最后,评估了各参数对碳纤维布寿命的影响。Composites Science and TechnologyThe strength prediction model of unidirectional fiber reinforced composites based on the renormalization group methodYixing Qian, Zhinan Li, Xin Zhou, Tong Xia, Yao Zhang, Zhenyu Yang, Dayong Hu, Zixing Ludoi:10.1016/j.compscitech.2024.110639 基于重整化群法的单向纤维增强复合材料强度预测模型When unidirectional fiber reinforced composites are subjected to longitudinal tensile loading and reach a critical failure state, they experience a sudden transition from local damage to catastrophic failure, commonly termed as an avalanche event. This paper integrates the self-organized criticality theory (SOC) concepts into the prediction of longitudinal tensile strength of composites and establishes a strength prediction model of composites based on the renormalization group method (RGM). The predictions of the RGM model are successfully validated against experimental results in the literatures, and it demonstrates relatively acceptable predictive accuracy compared to classical strength criteria. Compared to other state-of-the-art prediction models considering stochastic fiber strength distribution, the RGM model effectively provides strength statistics for fiber bundles of any size and describes the occurrence of composites avalanche failure induced by local stress concentration. This present model can be very conveniently implemented as a User Material Subroutine (UMAT) for finite simulations, facilitating practical prediction of the strength of composite structures.当单向纤维增强复合材料受到纵向拉伸载荷并达到临界破坏状态时,它们会经历从局部损伤到灾难性破坏的突然转变,通常被称为雪崩事件。将自组织临界理论(SOC)概念融入到复合材料纵向拉伸强度预测中,建立了基于重整化群法(RGM)的复合材料强度预测模型。RGM模型的预测结果与文献中的实验结果进行了对比验证,与经典强度准则相比,RGM模型的预测精度相对较好。与考虑随机纤维强度分布的其他最新预测模型相比,RGM模型有效地提供了任何尺寸纤维束的强度统计数据,并描述了局部应力集中引起的复合材料雪崩破坏的发生。该模型可以很方便地作为有限模拟的用户材料子程序(UMAT)实现,便于对复合材料结构的强度进行实际预测。来源:复合材料力学仿真Composites FEM

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