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【新文速递】2024年11月1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 1 篇,Composites Science and Technology 2 篇

Composite Structures

A mean field homogenization model for the mechanical response of ceramic matrix composites

Kevin Spilker, Ricardo A. Lebensohn, George Jacobsen, Laurent Capolungo

doi:10.1016/j.compstruct.2024.118630

陶瓷基复合材料力学响应的平均场均匀化模型

SiC/SiC composites offer exceptional mechanical stability at high temperatures and under irradiation. These ceramic matrix composites are therefore strong candidate materials for future nuclear energy applications. Their mechanical response, which exhibits pseudo-plasticity, is mediated by matrix cracking, fiber debonding, and fiber pull-out due to slip. This study introduces a mechanistic model for the behavior of unidirectionally reinforced SiC/SiC composites. Specifically a mean field homogenization approach is proposed to account for all deformation and degradation modes during mechanical deformation. The homogenization scheme relies on a Mori Tanaka method that is extended to consider the effects of the coating’s elasto-plastic response on the development of micromechanical fields. Further, the model proposed introduces a method to effectively account for the role of localized damage (i.e., cracks) on mechanical fields within both the fiber and the matrix. Upon validating the model against experimental data, the roles of interface sliding, coating dimensions and intrinsic elastic response, as well as of microstructure (e.g. porosity, fiber volume fraction) are discussed.

SiC/SiC复合材料在高温和辐照下具有优异的机械稳定性。因此,这些陶瓷基复合材料是未来核能应用的强有力的候选材料。它们的力学响应表现为伪塑性,是由基体开裂、纤维脱粘和纤维因滑移而拉出介导的。介绍了单向增强SiC/SiC复合材料性能的机理模型。具体来说,提出了一种平均场均匀化方法来解释机械变形过程中的所有变形和退化模式。均匀化方案依赖于Mori Tanaka方法,该方法扩展到考虑涂层弹塑性响应对微力学场发展的影响。此外,所提出的模型引入了一种方法来有效地考虑纤维和基体内部的局部损伤(即裂纹)在力学场中的作用。根据实验数据验证了模型,讨论了界面滑动、涂层尺寸和固有弹性响应以及微观结构(如孔隙率、纤维体积分数)的作用。


Mode I crack propagation in polydimethylsiloxane-short carbon fiber composites

Nan Hou, Qiang Guo, Fahmi Zaïri, Ning Ding

doi:10.1016/j.compstruct.2024.118682

聚二甲基硅氧烷-短碳纤维复合材料的I型裂纹扩展

This paper presents a comprehensive analysis of reinforcement toughening and failure mechanisms in polydimethylsiloxane (PDMS)-carbon fiber (CF) composites employing an approach combining experiments and numerical simulations. Through a series of meticulously designed mechanical experiments, the behavior of the composite material under varying conditions is thoroughly examined. The introduction of CFs enhances the stiffness of the material while also leading to debonding and an increased Mullins effect. A constitutive model replicating the observed reinforcement and damage behavior is implemented. Our investigation extends to the analysis of crack growth through both numerical simulations and microscopic morphological examinations. A cohesive zone model is subsequently utilized to simulate crack propagation, providing enhanced understanding of the relationship between structural characteristics and mechanical behaviors. The process of crack propagation subjects the materials to cycles of loading and unloading, highlighted by the reinforcing action of CF pinning and stress transfer, alongside toughening mechanisms attributed to a variety of dissipative processes: interfacial debonding damage, energy loss due to CF pull-out, the Mullins effect, and viscous energy dissipation. This study elucidates the complex mechanical interplay within PDMS-CF composites and suggests pathways for their design optimization, significantly broadening their applicability in numerous domains.

采用实验与数值模拟相结合的方法,对聚二甲基硅氧烷(PDMS)-碳纤维(CF)复合材料的增强增韧及失效机理进行了综合分析。通过一系列精心设计的力学实验,彻底检查了复合材料在不同条件下的行为。碳纤维的引入提高了材料的刚度,同时也导致了脱粘和增加的马林斯效应。一个本构模型复 制观察到的钢筋和损伤行为实现。我们的研究扩展到裂纹扩展的分析,通过数值模拟和微观形态检查。随后利用内聚区模型来模拟裂纹扩展,从而更好地理解结构特征与力学行为之间的关系。裂纹扩展过程使材料受到加载和卸载循环的影响,突出表现为CF钉钉和应力传递的增强作用,以及归因于各种耗散过程的增韧机制:界面脱粘损伤、CF拉出导致的能量损失、Mullins效应和粘性能量耗散。本研究阐明了PDMS-CF复合材料内部复杂的力学相互作用,并为其设计优化提供了途径,大大拓宽了其在许多领域的适用性。


Identification of component material in-situ properties of C/SiC composites based on self-consistent clustering analysis and Bayesian method

Bo Gao, Xinhang Dai, Hongyue Wang, Xinliang Zhao, Chenghai Xu, Qiang Yang, Songhe Meng

doi:10.1016/j.compstruct.2024.118686

基于自一致聚类分析和贝叶斯方法的C/SiC复合材料原位性能识别

In the paper, a method for identifying the mechanical properties of the in-situ component materials in carbon fiber reinforced silicon carbide ceramic matrix composites based on the macro mechanical test data is proposed. Firstly, the computation efficiency of considering damage behavior in the meso-mechanial model is improved through the self-consistent clustering analysis. Subsequently, sensitivity analysis is introduced in the parameter identification based on the Bayesian network to reduce the number of parameters to be identified simultaneously, thereby alleviating the ill-posedness of the inverse problem. Numerical and experimental cases were conducted to validate the proposed method. The maximum error of parameter identification is 6.0 % and the prediction error for strength is only 1.7 % in the numerical case with 5 % Gaussian noise. In the experimental case, the stress–strain curve calculated using the identified results shows good agreement with the experimental data. The prediction error for strength is only 2.2 %, while the maximum deviation between the identified results and the reference value in the literature can be up to 50 %, indicating the importance of obtaining the properties of component materials in-situ.

本文提出了一种基于宏观力学试验数据的碳纤维增强碳化硅陶瓷基复合材料原位构件材料力学性能鉴定方法。首先,通过自洽聚类分析提高细观力学模型中考虑损伤行为的计算效率;随后,在基于贝叶斯网络的参数识别中引入灵敏度分析,减少了同时需要识别的参数数量,从而减轻了反问题的病态性。通过数值和实验验证了该方法的有效性。在高斯噪声为5 %的数值情况下,参数辨识的最大误差为6.0 %,强度预测误差仅为1.7 %。在实验情况下,利用识别结果计算的应力-应变曲线与实验数据吻合较好。强度预测误差仅为2.2 %,而识别结果与文献参考值的最大偏差可达50 %,说明原位获取构件材料性能的重要性。


Composites Part A: Applied Science and Manufacturing

Reliable longitudinal electrical conductivity characterisation of unidirectional CFRP tapes

Y.M. Buser, E.T.M. Krämer, R. Akkerman, W.J.B. Grouve

doi:10.1016/j.compositesa.2024.108550

单向CFRP胶带可靠的纵向导电性表征

Induction welding is a promising assembly method for carbon fibre reinforced thermoplastic composites. In this process, an alternating electromagnetic field induces eddy currents in a composite susceptor. Accurate determination of the electrical conductivity of the carbon fibre network is essential for the development of physics-based simulations of the process. This work focuses on characterisation of the longitudinal electrical conductivity of unidirectionally reinforced paek using the six-probe method. Special attention is given to validating the boundary conditions and assumptions underlying the experimental procedure. The experimental results show that the longitudinal electrical conductivity consistently adheres to the rule of mixtures; nevertheless, achieving this finding proves sensitive to the care put into the procedural execution. Additionally, the study provides a valuable dataset for various commercially available tapes relevant to the aerospace industry.

感应焊是一种很有前途的碳纤维增强热塑性复合材料组装方法。在这个过程中,交变电磁场在复合感受器中产生涡流。准确测定碳纤维网络的电导率对于开发基于物理的过程模拟至关重要。本工作的重点是利用六探针方法表征单向增强paek的纵向电导率。特别注意验证边界条件和假设的实验过程。实验结果表明:纵向电导率始终遵循混合规律;然而,实现这一发现证明对程序执行的谨慎是敏感的。此外,该研究还为与航空航天工业相关的各种商用磁带提供了有价值的数据集。


Hierarchical hollow MnO/carbon fiber@WS2 composite material exhibits strong wideband electromagnetic wave attenuation

Xiaoxiao Zhao, Ying Huang, Huiyang Jiang, Xudong Liu, Xiaofang Ma, Panbo Liu, Meng Zong

doi:10.1016/j.compositesa.2024.108565

 

分层中空MnO/碳fiber@WS2复合材料表现出较强的宽带电磁波衰减

Constructing multi-layer heterogeneous interfaces has been studied as one of the important means to optimize electromagnetic wave absorption performance. WS2, as a special layered material with high specific surface area and multiple anionic vacancies, although its multi-layered interface structure cannot meet the requirements of all absorbing materials, composite absorbers designed through composition and structure are undoubtedly not one of the strategies to improve absorption bandwidth. In this study, we utilized the defect rich characteristics of WS2 Nano flowers and designed a multi-layer core–shell MnO/CF@WS2 (H-MCW) hybrid materials using carbon fiber (CF) as a carrier to provide a carbon source. The core cavity of H-MCW is conducive to multiple scattering of electromagnetic waves, with a large number of defects leading to an increase in electrochemical active sites in the material, and enhanced dipoles helping to improve impedance matching. This work provides a new method for designing lightweight thin film absorbing materials.

构建多层非均质界面是优化电磁波吸收性能的重要手段之一。WS2作为一种具有高比表面积和多个阴离子空位的特殊层状材料,虽然其多层界面结构不能满足所有吸波材料的要求,但通过成分和结构设计复合吸波材料无疑不是提高吸波带宽的策略之一。本研究利用WS2纳米花缺陷丰富的特点,设计了以碳纤维(CF)为载体提供碳源的多层核壳MnO/CF@WS2 (H-MCW)杂化材料。H-MCW的芯腔有利于电磁波的多次散射,大量的缺陷导致材料中电化学活性位点的增加,偶极子的增强有助于改善阻抗匹配。本工作为设计轻量化薄膜吸波材料提供了一种新的方法。


Composites Part B: Engineering

Temperature and rate dependent shear characterization and modeling of spread-tow woven Flax/PP composite laminates

Ramak Hossein Abadi, Kalliopi-Artemi Kalteremidou, Javane Karami, Danny Van Hemelrijck

doi:10.1016/j.compositesb.2024.111930

拉伸-拖曳亚麻/PP复合层压板的温度和速率相关剪切特性和建模

This paper investigates the in-plane shear behavior of spread-tow woven structured flax fiber-reinforced polypropylene composites, focusing on temperature and displacement rate effects. For this aim, the study includes bias-extension experiments to characterize the shear behavior of the material. Several experiments were conducted at different displacement rates and temperature levels. The temperature levels were chosen to encompass the material's behavior during solid and molten-state thermoforming, given the melting and decomposition temperatures acquired from differential scanning calorimetry and thermogravimetric analysis tests, respectively. A new fixture was designed and manufactured to allow pre-heating of the oven and rapid placement of the samples, which in turn, prevents their degradation for the time duration required to reach a uniform temperature distribution in the oven. During the experiments, the 3D digital image correlation technique accurately measured local deformations and strains on the specimen's surface under varying conditions. Further, a finite element model is developed, incorporating a fiber reorientation algorithm with a hypo-elastic shear model to simulate the material's temperature and rate-dependent behavior. The finite element shear angle distributions, as well as the shear angle-force and shear angle-displacement curves, are compared with the Digital Image Correlation (DIC) data and load measurements for different test conditions, showing good agreement between the numerical and experimental approaches.

本文研究了展拖编织结构亚麻纤维增强聚丙烯复合材料的面内剪切性能,重点研究了温度和位移速率的影响。为此,研究包括偏伸实验来表征材料的剪切行为。在不同的驱替速率和温度水平下进行了多项实验。根据差示扫描量热法和热重分析测试分别获得的熔化和分解温度,所选择的温度水平涵盖了材料在固态和熔融状态热成型过程中的行为。设计和制造了一种新的夹具,以允许烤箱预热和快速放置样品,这反过来又可以防止它们在达到烤箱均匀温度分布所需的时间内降解。在实验过程中,三维数字图像相关技术精确测量了不同条件下试件表面的局部变形和应变。此外,开发了一个有限元模型,结合纤维定向算法和亚弹性剪切模型来模拟材料的温度和速率依赖行为。将有限元剪切角分布以及剪切角-力和剪切角-位移曲线与不同试验条件下的数字图像相关(DIC)数据和载荷测量结果进行了比较,结果表明数值方法与实验方法吻合较好。


Composites Science and Technology

Fabrication and mechanical properties of CFRP honeycomb cylinder based on the transforming from the flat honeycombs

Zhibin Li, Pengcheng Xue, Jian Xiong

doi:10.1016/j.compscitech.2024.110948

 

基于平板蜂窝改造的CFRP蜂窝筒的制造及其力学性能

Nature has long inspired the design of high-performance structures, offering profound insights into engineering innovations through intricate biological architectures. The rational design of composite curved components is crucial for the lightweight construction of aerospace structures. In the transition from planar constructs to curved components, any mismatch in form can induce high stress, potentially leading to structural compromise or failure. Drawing inspiration from the water lily, a rational design and fabrication approach for cylindrical surface structures is proposed, transitioning from planar to curved surfaces. The adaptation of zero Poisson's ratio honeycomb to cylindrical surface is verified by experiments and simulations. The mismatch relationship between them would lead to the damage failure of the honeycomb. In view of this, the honeycomb sandwich cylinder commonly used in aerospace is fabricated by the proposed method. Using this approach, a honeycomb sandwich cylinder—commonly utilized in aerospace applications—was fabricated. Theoretical predictions and experimental characterizations were conducted to analyze failure modes under axial compression. This led to the creation of a failure mechanism map for the honeycomb cylinder. Load-mass efficiency analysis revealed that face-crushing failure provides high bearing efficiency. Additionally, the effects of facesheet thickness, along with a comparison of failure modes and imperfection sensitivity between single and sandwich cylinders, were explored. The results indicate that the sandwich cylinder exhibits a higher specific load-bearing capacity and lower imperfection sensitivity compared to the single cylinder.

长期以来,大自然激发了高性能结构的设计灵感,通过复杂的生物结构为工程创新提供了深刻的见解。复合材料曲面构件的合理设计是航空航天结构轻量化的关键。在从平面结构到弯曲构件的过渡过程中,任何形式的不匹配都可能引起高应力,从而可能导致结构妥协或失效。从睡莲中获得灵感,提出了一种由平面过渡到曲面的圆柱形表面结构的合理设计和制造方法。通过实验和仿真验证了零泊松比蜂窝对圆柱表面的适应性。它们之间的不匹配关系将导致蜂窝的破坏破坏。为此,采用该方法制备了航空航天中常用的蜂窝夹层筒体。利用这种方法,制造了一个蜂窝夹层圆柱体-通常用于航空航天应用。进行了理论预测和实验表征,分析了轴压作用下的破坏模式。这导致了蜂窝圆柱体失效机理图的创建。载荷-质量效率分析表明,面压破坏提供了较高的承载效率。此外,还探讨了面板厚度的影响,以及单柱和夹层柱之间的失效模式和缺陷灵敏度的比较。结果表明:夹层筒体比单一筒体具有更高的比承载能力和更低的缺陷敏感性;


Improving the high-voltage insulation properties of polypropylene by introducing trace addition of polyvinylidene fluoride: An experimental and simulation study

Ohuk Lee, Do-Kyun Kim, Hana Kim, Seong Hwan Lee, Taehoon Kwon, Ik-Su Kwon, Keisuke Shinozaki, Masayuki Hikita, Jin Hong Lee, Dae Ho Lee, Min Hee Kim, Masahiro Kozako, Seunggun Yu

doi:10.1016/j.compscitech.2024.110939

 

引入微量聚偏氟乙烯改善聚丙烯高压绝缘性能的实验与模拟研究

Various additives ranging from inorganic nanoparticles to organic additives have been suggested to improve the insulation performance of polymeric materials for high-voltage engineering applications. Herein, a simple method for doping fluorine into a polypropylene (PP) matrix was presented by melt-blending of isotactic PP (iPP) with a small amount of polyvinylidene fluoride (PVDF) as a thermoplastic voltage stabilizer (TVS). During melt-mixing, the PVDF TVS, which is immiscible with PP, is gradually split into smaller domains within the iPP matrix and finely distributed, especially at a low PVDF content. The direct current (DC) breakdown strength (BDS) values of the PVDF-doped iPP increased by 110% and 149% at 25 and 110 °C, respectively, compared to those of the pristine PP, while its dielectric permittivity and loss tangent values remained nearly similar to those of iPP at wide temperature between 25 and 140 °C and frequency range between 1 Hz and 10 MHz. Quantum chemical simulation results reveal that a small amount of PVDF with high dipole moment introduces deep trap sites within the polymer matrix, which contribute for increasing BDS of iPP. Also, the PP with a small amount of PVDF dopants below 1.0 phr exhibited no any decrease in the tensile strength and elongation at break values. Therefore, the PVDF-doped iPP is anticipated as a potential candidate as high-performance high-voltage insulation materials for next-generation insulation applications.

从无机纳米颗粒到有机添加剂的各种添加剂已被建议用于改善高压工程应用的聚合物材料的绝缘性能。本文提出了一种将氟掺杂到聚丙烯(PP)基体中的简单方法,即将等规聚丙烯(iPP)与少量聚偏氟乙烯(PVDF)熔融共混作为热塑性稳压器(TVS)。在熔融混合过程中,与PP不相混的PVDF tv在iPP基体中逐渐分裂成更小的区域并精细分布,特别是在PVDF含量低的情况下。在25°C和110°C下,掺pvdf的iPP的直流击穿强度(BDS)值分别比未掺pvdf的iPP提高了110%和149%,而在25 ~ 140°C的宽温度和1 Hz ~ 10 MHz的频率范围内,其介电常数和损耗正切值与未掺pvdf的iPP保持接近。量子化学模拟结果表明,少量具有高偶极矩的PVDF在聚合物基体中引入了深阱位点,这有助于提高iPP的BDS。此外,在1.0 phr以下,添加少量PVDF的PP的拉伸强度和断裂伸长率没有下降。因此,pvdf掺杂iPP有望成为下一代高性能高压绝缘材料的潜在候选材料。




来源:复合材料力学仿真Composites FEM
ACTMechanicalAdditiveInspireMAGNET断裂复合材料化学航空航天核能裂纹理论材料试验曲面
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【新文速递】2024年10月30日复合材料SCI期刊最新文章

今日更新:Composite Structures 3 篇,Composites Part A: Applied Science and Manufacturing 4 篇,Composites Part B: Engineering 3 篇,Composites Science and Technology 5 篇Composite StructuresLow-velocity impact and quasi-static post-impact compression analysis of woven structural composites for automotive: Influence of fibre types and architectural structuresSandeep Olhan, Bindu Antil, B.K. Beheradoi:10.1016/j.compstruct.2024.118676汽车编织结构复合材料的低速冲击和准静态冲击后压缩分析:纤维类型和建筑结构的影响This paper studied the effect of different fibres and their architectures on the low-velocity impact (LVI) and quasi-static compression after impact (CAI) characteristics of textile fibre-based structural composite materials (TFSCM) manufactured using the vacuum-assisted resin transfer molding (VARTM) method. All specimens were tested at three distinct impact energy levels: 20 J, 30 J, and 40 J. Subsequently, optical microscopy, field emission scanning electron microscope (FESEM), and 3D X-ray micro-computed tomography (µ-CT) techniques were utilized to examine and analyze the internal and external damage morphologies, failure mechanisms, and damage distribution within the structural composites. The experimental findings revealed that the basalt epoxy-based three-dimensional (3D) woven fabric-reinforced composites had superior energy absorption and deformation resistance than the glass and sisal-based unidirectional (UD) and bidirectional (2D) composites across all impact energy levels. Furthermore, µ-CT analysis showed that specimens impacted at 40 J experienced a 128.41 % and 154.36 % increase in damage volume compared to those impacted at 30 J and 20 J, leading to complete perforation damage and z-yarn bending and breakage without any delamination at the impact site. More importantly, composites reinforced with UD preforms impacted at 10 J exhibited higher CAI strength compared to both 2D and 3D composites.研究了不同纤维及其结构对真空辅助树脂传递模塑(VARTM)方法制备的纺织纤维基结构复合材料(TFSCM)低速冲击(LVI)和准静态冲击后压缩(CAI)特性的影响。所有的样本都在三种不同的冲击能量水平下进行了测试:20 J, 30 J和40 J。随后,利用光学显微镜、场发射扫描电镜(FESEM)和三维x射线微计算机断层扫描(µ-CT)技术对结构复合材料内部和外部损伤形态、破坏机制和损伤分布进行了检查和分析。实验结果表明,玄武岩环氧树脂基三维(3D)机织增强复合材料在所有冲击能级上都比玻璃基和剑麻基单向(UD)和双向(2D)复合材料具有更好的吸能和抗变形能力。此外,微ct分析表明,与受30 J和20 J冲击的试件相比,受40 J冲击的试件的损伤体积分别增加了128.41 %和154.36 %,导致了完全的穿孔损伤和z纱弯曲和断裂,而在冲击部位没有发生分层。更重要的是,与2D和3D复合材料相比,受10 J冲击的UD预制体增强的复合材料具有更高的CAI强度。A novel three-dimensional DEM model for recycled aggregate concrete considering material heterogeneity and microcrack evolutionHaiyang Zhao, Annan Zhou, Liangchi Zhang, Arul Arulrajahdoi:10.1016/j.compstruct.2024.118677考虑材料非均质性和微裂纹演化的再生骨料混凝土三维DEM模型Recycled aggregate concrete presents significant potential for sustainable construction. However, its widespread adoption is impeded by a lack of comprehensive understanding of how recycled aggregates impact its mechanical properties. This paper proposes an advanced discrete element model accurately representing the concrete’s meso-structure, including diverse interfacial transition zones, random adhering mortar distributions as well as heterogeneous material properties. Furthermore, this model also allows for the identification and dynamic monitoring of microcrack initiation and propagation. Results show that low-quality recycled aggregates promote direct crack propagation through the aggregates, significantly impairing concrete performance. Adhering mortar negatively impacts concrete properties due to its poor interfacial bond with the mortar matrix and its inferior mechanical properties. The influence of the replacement ratio on the concrete properties is closely tied to the recycled aggregate quality. High-quality aggregates allow for higher replacement ratios with limited property degradation in the concrete.再生骨料混凝土为可持续建筑提供了巨大的潜力。然而,由于缺乏对再生骨料如何影响其机械性能的全面了解,其广泛采用受到阻碍。本文提出了一种先进的离散元模型,该模型准确地反映了混凝土的细观结构,包括不同的界面过渡区、随机粘接砂浆分布以及非均质材料特性。此外,该模型还允许识别和动态监测微裂纹的起裂和扩展。结果表明:低质量再生骨料促进裂缝直接穿过骨料扩展,严重影响混凝土性能;粘结砂浆与砂浆基体界面粘结性差,力学性能差,对混凝土性能产生负面影响。替代率对混凝土性能的影响与再生骨料质量密切相关。高质量的骨料在混凝土性能退化有限的情况下允许更高的替代率。Fracture properties of carbon/glass fiber composite laminates with surface scratch damagePingping Luo, Wei Shen, Lifeng Chen, Zijia Yao, Qian Li, Lvtao Zhudoi:10.1016/j.compstruct.2024.118673表面划伤损伤的碳/玻璃纤维复合材料层合板断裂性能Carbon/glass fiber reinforced polymer composite panels may experience minor surface scratches during processing or use. These shallow scratches can expand and potentially lead to dangerous fracture failure as the specimens are continually loaded. This study presents a closed form non-LEFM model for predicting the fracture performance of materials with slight scratches. First, 3-p-b tests and direct tensile tests were conducted on 115 carbon/glass fiber composite laminated panel specimens. A comparison of the two test methods revealed that 3-p-b tests were more suitable for analyzing quasi-brittle fracture in carbon/glass fiber composites. The tensile strength ft and fracture toughness KIC of 3-p-b specimens with and without notched were discussed using the weighted average calculation method to determine the thickness of the “composite” single-layer prepreg as the characteristic composite unit Cch. A normal distribution method was also introduced to analyze the experimental discrete points, covering almost all the experimental scatterers with desired reliability. Furthermore, the same method was applied to specimens with different layup methods, and the data analysis confirmed its effectiveness. As the seam-thickness ratio α increases within a certain range, the tensile strength ft showed an overall increasing trend and the peak load Pmax showed a decreasing trend. Additionally, the laboratory routine dimensions can be utilized to efficiently predict the fracture of large size members with defects at the same thickness, which is significant for the safe design of composite structures.碳/玻璃纤维增强聚合物复合板材在加工或使用过程中可能会出现轻微的表面划痕。这些浅表划痕可能会随着试样的持续加载而扩大,并可能导致危险的断裂失效。本研究提出了一种封闭形式的非局部塑性应力模型,用于预测带有轻微划痕材料的断裂性能。首先,对115块碳/玻璃纤维复合层压板试样进行了3Pb测试和直接拉伸测试。比较两种测试方法发现,3Pb测试更适合分析碳/玻璃纤维复合材料的准脆性断裂。采用加权平均计算方法讨论了带有和不带有缺口的3Pb试样的拉伸强度ft和断裂韧性KIC,并确定了作为特征复合单元Cch的“复合”单层预浸料的厚度。还引入了正态分布方法来分析实验离散点,以覆盖几乎全部实验散点,并达到所需的可靠性。此外,该方法还应用于不同铺层方法的试样,数据分析证实了其有效性。当缝隙厚度比α在一定范围内增大时,拉伸强度ft总体上呈上升趋势,峰值载荷Pmax呈下降趋势。此外,实验室常规尺寸可用于高效预测相同厚度有缺陷的大尺寸构件的断裂,这对于复合结构的安全设计具有重要意义。Composites Part A: Applied Science and ManufacturingEnhancements of physical microstructure and chemical activation on interfacial bonding strength of carbon fiber reinforced polymerChengcheng Sun, Peng Gu, Hailang Wan, Mingjun Ren, Jianping Lin, Junying Mindoi:10.1016/j.compositesa.2024.108530物理微观结构和化学活化对碳纤维增强聚合物界面结合强度的影响Carbon fiber reinforced polymer (CFRP) has wide applications in aerospace and medical industries due to the characteristics of high strength and corrosion resistance. However, surface treatment is generally required to improve its interfacial bonding strength. This study employed imprinting and plasma treatments for physical and chemical modifications on CFRP surface. Results indicate that changing the groove orientation from 0° to 90° increased the interface bonding strength by 20.8% due to the reduction of stress concentration at the bonding interface. Air plasma treatment not only removes surface contaminants but also generates chemical functional groups, such as amino and hydroxyl, on CFRP surface, which enhances the bonding strength by 266.3%. Hydroxyl and amino groups increase van der Waals and Coulombic forces between CFRP surface and adhesive molecule. Therefore, this study proposes a coupling method of imprinting and plasma treatment to maximize the interfacial bonding strength of CFRP.碳纤维增强聚合物(CFRP)具有高强度和耐腐蚀的特点,在航空航天和医疗工业中有着广泛的应用。然而,通常需要进行表面处理以提高其界面结合强度。本研究采用印迹和等离子体处理对CFRP表面进行物理和化学改性。结果表明,当坡口方向由0°变为90°时,界面结合强度提高了20.8%,这是由于结合界面处的应力集中减少所致。空气等离子体处理不仅能去除CFRP表面的污染物,还能在CFRP表面生成氨基、羟基等化学官能团,使CFRP的结合强度提高266.3%。羟基和氨基增加了CFRP表面与粘附分子之间的范德华力和库仑力。因此,本研究提出了一种印迹和等离子体处理的耦合方法,以最大限度地提高CFRP的界面结合强度。A friction-based method for measuring the radial compaction response of fibre towsJ. Hares, P. Kelly, M. Battley, S. Bickertondoi:10.1016/j.compositesa.2024.108541一种基于摩擦的纤维束径向压实响应测量方法High performance fibre reinforced composite components are typically compacted to a high fibre volume fraction during manufacture. As such, it is important to understand the compaction behaviour of these materials to better design and model composite manufacturing processes. While most manufacturing processes apply transverse compaction pressure to planar textiles, continuous fibre composite 3D printing processes can apply a radial compaction pressure to a single tow in the printing nozzle. A similar mode of compaction is also seen in processes such as pultrusion of circular cross-sections. This work describes a new friction-based method for measuring the radial compaction response of single tows, or groups of tows. The radial compaction behaviour of a single 40K carbon fibre tow is measured and presented. Radial compaction of the characterised tow showed a steeper nonlinear relationship between compaction pressure and fibre volume fraction, than typically found for transverse compaction of 2D textile reinforcements.高性能纤维增强复合材料组件通常在制造过程中被压实到高纤维体积分数。因此,了解这些材料的压实行为对于更好地设计和模拟复合材料制造工艺非常重要。虽然大多数制造工艺对平面纺织品施加横向压实压力,但连续纤维复合材料3D打印工艺可以对打印喷嘴中的单个束施加径向压实压力。在圆形截面的拉挤等过程中也可以看到类似的压实模式。这项工作描述了一种新的摩擦为基础的方法来测量径向压实响应的单束,或组束。测量并介绍了40K碳纤维束的径向压实性能。特征束的径向压实在压实压力和纤维体积分数之间表现出更陡峭的非线性关系,而不是典型的二维纺织增强材料的横向压实。Fabrication of core–shell nickel ferrite@polypyrrole composite for broadband and efficient electromagnetic wave absorptionRuiwen Shu, Kunlong Yun, Xinyue Liu, Leilei Xudoi:10.1016/j.compositesa.2024.108558 宽带高效电磁波吸收核壳镍ferrite@polypyrrole复合材料的制备Herein, nickel ferrite@polypyrrole (NiFe2O4@PPy) composite was prepared by a simple two-step route of solvothermal synthesis and in-situ oxidation polymerization reaction. The results of micromorphology analysis showed that the obtained NiFe2O4@PPy composite had a unique core–shell structure, good magnetic performance and electrical conductivity. Furthermore, the as-prepared magnetic/conductive NiFe2O4@PPy composite exhibited notably enhanced electromagnetic wave (EMW) absorption performance than pure NiFe2O4 and PPy. When the filling ratio was 17.5 wt% and the matching thickness was 2.24 mm, the optimal minimum reflection loss (RLmin) of −56.25 dB and a broad effective absorption bandwidth (EAB) of 5.2 GHz were achieved for NiFe2O4@PPy composite. With slightly increasing the matching thickness to 2.6 mm, the maximum EAB of 7.12 GHz could be reached. Additionally, the probable EMW absorption mechanism was elucidated. Therefore, this work could provide a valuable reference for the preparation of magnetic ferrite/conductive polymer composites as broadband and high-efficiency EMW absorbers.在本工作中,采用简单的两步法——溶剂热合成和原位氧化聚合反应制备了镍铁氧体@聚吡咯(NiFe2O4@PPy)复合材料。微观形貌分析结果表明,制得的NiFe2O4@PPy复合材料具有独特的核壳结构,具有良好的磁性能和电导率。此外,制备的磁性/导电NiFe2O4@PPy复合材料的电磁波吸收性能显著优于纯NiFe2O4和PPy。当填充率为17.5 wt%,匹配厚度为2.24 mm时,NiFe2O4@PPy复合材料的理想最小反射损耗(RLmin)为-56.25 dB,有效吸收带宽(EAB)为5.2 GHz。将匹配厚度略微增加到2.6 mm时,最大EAB为7.12 GHz。此外,还阐明了可能的电磁波吸收机制。因此,该工作可为制备宽带、高效电磁波吸收剂的磁性铁氧体/导电聚合物复合材料提供有价值的参考。Flexible conductive adhesives with high conductivity and infrared stealth performanceChengwei Jiang, Chunfang Zi, Jing Li, Changxiang Hao, Shaoyong Cai, Yiqi Xu, Fengyu Su, Ge Cao, Yanqing Tiandoi:10.1016/j.compositesa.2024.108559具有高导电性和红外隐身性能的柔性导电胶粘剂While extensively employed in electronic packaging, the prevailing electrically conductive adhesives (ECAs) are currently constrained by their lack of flexibility, excessive manufacturing costs, and limited multifunctionality. In this work, the antimony-doped tin oxide flexible conductive adhesives (AFCAs) were prepared by incorporating the antimony-doped tin oxide (ATO) nanoparticles into a thermoplastic polyurethane (TPU) matrix along with silver flakes. The ATO nanoparticles acted as conductive bridges for sliver flakes to enhance the electrical conductivity and mechanical integrity of the composites. The AFCAs formulated with a mere 60 % Ag and 7 % ATO nanoparticles exhibited an exceptionally low volume resistivity of 2.01 × 10-5 Ω·cm. After 10,000 mechanical bending cycles, the resistance change of AFCAs was only 8 %. Remarkably, the AFCA films also demonstrated excellent infrared stealth capabilities by infrared thermal imaging. This study demonstrates a facile strategy to develop high-performance and multifunctional AFCAs for flexible electrics with excellent electrical stability and infrared stealth capabilities.虽然广泛应用于电子封装,但目前普遍使用的导电粘合剂(eca)由于缺乏灵活性,制造成本过高和多功能性有限而受到限制。在这项工作中,将掺锑氧化锡(ATO)纳米颗粒与银片一起掺入热塑性聚氨酯(TPU)基体中,制备了掺锑氧化锡柔性导电胶粘剂(AFCAs)。ATO纳米颗粒作为银片的导电桥,提高了复合材料的导电性和机械完整性。仅含有60 % Ag和7 % ATO纳米粒子的AFCAs具有非常低的体积电阻率,为2.01 × 10-5 Ω·cm。经过1万次机械弯曲循环后,AFCAs的电阻变化仅为8 %。值得注意的是,AFCA薄膜还通过红外热成像显示了出色的红外隐身能力。该研究展示了一种开发高性能多功能柔性电气afca的简单策略,该afca具有优异的电气稳定性和红外隐身能力。Composites Part B: EngineeringUnleashing the elastocaloric cooling potential of 3D-printed NiTi alloy with heterogeneous microstructures and Ni4Ti3 nanoparticlesJianbin Zhan, Ruijin Ma, Liang Zhu, Jiahui Fang, Kun Li, David Z. Zhang, Lawrence E. Murrdoi:10.1016/j.compositesb.2024.111918 释放具有非均相组织和Ni4Ti3纳米颗粒的3d打印NiTi合金的弹热冷却潜力Toward the development of elastocaloric (eC) refrigeration applications, this study examines how Ni4Ti3 nanoparticles improve the eC properties of laser powder bed-fused (LPBF) NiTi alloys, with a focus on the formation of a NiTi/Ni4Ti3 nanocomposite. The LPBF-produced microstructure offers significant advantages: i) a heterogeneous grain structure that provides complementary benefits—fine grains offer higher deformation resistance while coarse grains initiate phase transformation (PT) earlier, releasing more latent heat; ii) a strong <001>//building direction texture that enhances recoverability. However, these benefits are partially limited by grain boundary slip during PT, leading to lower cooling efficiency and increased energy dissipation in as-built NiTi alloys. To address these issues, Ni4Ti3 nanoparticles are introduced through aging treatment, forming a composite structure that strengthens grain boundaries. Given the challenges of applying severe plastic deformation to 3D-printed components, this approach may offer a more practical solution. The study also reveals that Ni4Ti3 nanoparticles contribute to: 1) reducing Ni content in the matrix, increasing lattice size and enthalpy, which enhances the temperature drop (ΔTad); and 2) promoting R phase formation, which hinders the B2↔B19' PT, reducing energy dissipation and improving the coefficient of performance (COPmat). The balance of these effects depends on nanoparticle size, with smaller particles (∼5–12 nm) amplifying the second effect, while larger particles (∼130 nm) increase the first effect. At 350°C aging, the optimized nanocomposite exhibits a maximum COPmat of 15 and ΔTad of 14K, representing a 163% improvement over the as-built alloy. This work highlights the potential of NiTi composites in 3D-printed eC components.本研究旨在推动弹性卡热(eC)制冷技术的发展,重点研究Ni4Ti3纳米粒子如何改善激光粉末床融合(LPBF)NiTi合金的eC性能,并专注于NiTi/Ni4Ti3纳米复合材料的形成。LPBF工艺产生的微观结构具有显著优势:i)异质的晶粒结构,提供互补的优点——细晶粒具有更高的塑性变形抵抗力,粗晶粒较早引发相变(PT),释放更多的潜热;ii)强烈的[001]//建筑方向织构,增强可恢复性。然而,这些优点在相变过程中的晶界滑移作用下受到部分限制,导致未经处理的NiTi合金冷却效率降低和能量损耗增加。为了解决这些问题,通过时效处理向合金中引入Ni4Ti3纳米粒子,形成一种增强晶界强度的复合结构。鉴于将严重塑性变形应用于3D打印组件的挑战,这种方法可能提供更实用的解决方案。该研究还表明,Ni4Ti3纳米颗粒有助于:1) 减少基体中的Ni含量,增大晶格尺寸和熵,从而提高温度下降量(ΔTad);2) 促进R相的形成,阻碍B2↔B19' PT,减少能量损耗并提高性能系数(COPmat)。这些效应的平衡取决于纳米颗粒的大小,较小的纳米颗粒(约5-12 nm)会放大第二种效应,而较大的纳米颗粒(约130 nm)会增加第一种效应。在350°C老化后,优化的纳米复合材料具有最大COPmat 15和ΔTad 14K,比原始合金提高了163%。这项工作强调了NiTi复合材料在3D打印电子元件中的潜力。A Novel Mechanism to Accelerate Stress Relaxation of Toughened Blends: Stress-Induced Core-Shell Morphological Reconstruction and Its Application in Thermoforming and Dimensional StabilizationJielong Lin, Shibing Ye, Yong Zhang, Xiaoyun Yang, Jiqing Liu, Long Chen, Hongyao Xudoi:10.1016/j.compositesb.2024.111910 一种加速增韧共混物应力松弛的新机制:应力诱导核壳形态重构及其在热成型和尺寸稳定中的应用Improving thermoforming efficiency and dimensional stability in thermoplastic products is a common challenge. This study investigates toughened polyamide 612 (PA612) blends made by adding maleic anhydride-functionalized SEBS (mSEBS) elastomers, along with high-density polyethylene (HDPE), polyphenylene Oxide (PPO), and polyphenylene Sulfide (PPS). Analyses showed that mSEBS forms a core-shell structure with HDPE or PPO and a sea-island structure with PPS in the PA612 matrix. The study uniquely examines how these structures affect stress relaxation. The results, modeled by a steady-state creep model, revealed that the core-shell structures reduced the characteristic relaxation time (λ) by over three orders of magnitude compared to PA612/mSEBS blends. Additionally, PA612/mSEBS/HDPE blends were more temperature-sensitive, reducing λ by six orders of magnitude compared to PA612/mSEBS/PPO blends. Further analysis showed that stress-induced core-shell morphological reconstruction (SCMR) significantly improved stress relaxation by promoting extensive plastic deformation and energy dissipation. These toughened PA612 blends exhibited excellent thermoforming efficiency and dimensional stability. A 3D finite element model confirmed SCMR as an effective strategy for stress relaxation, providing valuable insights for designing toughened blends with superior processing efficiency and stability.提高热塑性塑料制品的热成型效率和尺寸稳定性是一个共同的挑战。本研究研究了通过添加马来酸酐功能化SEBS (mSEBS)弹性体以及高密度聚乙烯(HDPE)、聚苯氧乙烯(PPO)和聚苯硫醚(PPS)制成的增韧聚酰胺612 (PA612)共混物。分析表明,在PA612基体中,mSEBS与HDPE或PPO形成核壳结构,与PPS形成海岛结构。这项研究独特地考察了这些结构如何影响压力放松。通过稳态蠕变模型模拟的结果表明,与PA612/mSEBS共混物相比,核壳结构将特征弛豫时间(λ)降低了3个数量级以上。此外,PA612/mSEBS/HDPE共混物对温度更敏感,与PA612/mSEBS/PPO共混物相比,λ降低了6个数量级。进一步分析表明,应力诱导的核壳形态重建(SCMR)通过促进广泛的塑性变形和能量耗散,显著改善了应力松弛。这些增韧PA612共混物表现出优异的热成型效率和尺寸稳定性。3D有限元模型证实了SCMR是一种有效的应力松弛策略,为设计具有卓越加工效率和稳定性的增韧共混物提供了有价值的见解。Effect of admixed silicone emulsion on water and chloride transport properties of concreteFengjiang Li, Yu Fu, Jiangwei Zhu, Yuchen Wu, Jie Hu, Haoliang Huang, Fanghua Lei, Jiangxiong Wei, Qijun Yudoi:10.1016/j.compositesb.2024.111916 掺合硅酮乳液对混凝土水氯输运性能的影响The addition of silicone is effective method for improving both surface and internal hydrophobicity of concrete, thus clarifying its effect on transport property of concrete is very important. In this study, both water and chloride transport properties of concrete incorporated with three silicone emulsions based on different active ingredients (silane oligomers or silane monomers) were evaluated and investigated. The results show that all three silicone emulsions exhibit no obvious negative effect on hydration and microstructure of cement paste; however, the admixed silicone emulsions increase both the thickness and porosity of ITZ in concrete. Therefore, the admixed silicone emulsions result in reduced compressive strength of concrete. Further, the incorporated silicone emulsions efficiently increase surface and internal water contact angle of concrete, thus mitigating both water absorption and chloride transport in concrete. Due to more pronounced interaction between silane oligomers and hydration products based on molecular dynamics simulation, the beneficial effect on improving hydrophobicity of concrete and halting water and chloride transport is more significant for the admixed silicone emulsion with silane oligomers as active ingredient.硅酮的加入是改善混凝土表面疏水性和内部疏水性的有效方法,因此阐明其对混凝土输运性能的影响是十分重要的。在本研究中,评估和研究了三种基于不同活性成分(硅烷低聚物或硅烷单体)的硅烷乳液掺入混凝土的水和氯离子传输性能。结果表明:三种硅酮乳液对水泥浆体水化和微观结构均无明显的负面影响;硅酮乳液的掺入增加了混凝土中ITZ的厚度和孔隙率。因此,掺入硅酮乳液会降低混凝土的抗压强度。此外,掺入的硅酮乳液有效地增加了混凝土的表面和内部水接触角,从而减轻了混凝土中的吸水率和氯离子的迁移。由于基于分子动力学模拟的硅烷低聚物与水化产物之间的相互作用更为明显,因此以硅烷低聚物为活性成分的混合硅酮乳液在改善混凝土疏水性和阻止水氯离子传输方面的有利作用更为显著。Composites Science and TechnologyFully automated measurement of the spatial distribution of both fibre length and orientation from micro-CT images of short fibre reinforced polymers.L.M. Martulli, M. Sordi, A. Dinosio, A. Bernasconidoi:10.1016/j.compscitech.2024.110943 从短纤维增强聚合物的微ct图像中自动测量纤维长度和方向的空间分布。The morphology of Short Fibre Reinforced Polymers (SFRPs) plays a fundamental role in determining their stiffness, strength and fracture behaviour. Measurements tools for the analysis of their microstructure are therefore of paramount importance. To this end, a fully automated algorithm able to segment single fibres from X-ray micro-computed tomography images was developed. This method was tailored to effortlessly reconstruct the microstructure of large volumes of material; in particular, to acquire fibre length, position and orientation, even dealing with low-resolution images. The algorithm was tested on different specimens of short glass fibre-reinforced polyamide and it was validated comparing the fibre orientation with the one obtained with commercial software analysis and the fibre length with the experimentally determined one. Therefore, the proposed algorithm allows to easily identify microstructural trends without requiring the usual complex evaluating procedures.短纤维增强聚合物(SFRPs)的形貌在决定其刚度、强度和断裂行为方面起着至关重要的作用。因此,用于分析其微观结构的测量工具至关重要。为此,开发了一种能够从x射线微计算机断层扫描图像中分割单个纤维的全自动算法。该方法适合于毫不费力地重建大量材料的微观结构;特别是,即使处理低分辨率图像,也能获得纤维的长度、位置和方向。在不同的短玻璃纤维增强聚酰胺试样上进行了实验,并将所得的纤维取向与商业软件分析结果进行了比较,将所得的纤维长度与实验测定的长度进行了比较,对算法进行了验证。因此,所提出的算法可以很容易地识别微观结构趋势,而不需要通常复杂的评估程序。Array infrared thermography for visualization of defects in bonded fiber reinforced polymer jointsXingxing Zou, Mengyao Li, Hao Xu, Xiaofeng Ludoi:10.1016/j.compscitech.2024.110930 阵列红外热成像技术用于粘结纤维增强聚合物接头缺陷的可视化Fiber reinforced polymer (FRP) is widely used in new and existing structures, however, interfacial defects in the bonded joints pose a significant threat to structural integrity. Therefore, detection of interfacial defects is imperative for ensuring structural safety. This study proposes array infrared thermography (IRT) as a novel non-destructive evaluation method to visualize interfacial defects. Array IRT provides uniform heat excitation within the spatial domain, which overcomes the problem of heat concentration by conventional IRT. Forty-five bonded FRP plate specimens were tested using array IRT, results of which show that interfacial defects can be accurately detected within (8h+8) s (where h is the thickness of the upper layer of FRP in mm). Array IRT achieves high accuracy in detecting shapes, particularly sharp corners of defects. A pre-processing method was proposed to eliminate the twisted angles of thermal camera and to more clearly show the defects in the thermograms. A database containing tested thermograms and the corresponding predefined defects was established. Intelligent algorithms - UNet, Deeplabv3, and YOLOv8 - were used to segment the defected regions for array IRT analysis, results of which show a precision of 95.8%, 94.4%, and 94.1%, respectively.纤维增强聚合物(FRP)在新建和既有结构中得到了广泛的应用,但其粘结接头的界面缺陷对结构的完整性构成了严重的威胁。因此,界面缺陷检测是保证结构安全的必要手段。本研究提出阵列红外热像仪(IRT)作为一种新的界面缺陷无损检测方法。阵列红外热成像在空间范围内提供均匀的热激发,克服了传统红外热成像的热集中问题。采用阵列红外热成像技术对45个粘结玻璃钢板试件进行了测试,结果表明,在(8h+8) s (h为玻璃钢上层厚度,单位为mm)内可以准确检测到界面缺陷。阵列IRT在检测形状,特别是缺陷的尖角方面具有很高的精度。提出了一种消除热像仪畸变的预处理方法,使热像图中的缺陷更清晰地显示出来。建立了一个包含测试热图和相应的预定义缺陷的数据库。利用UNet、Deeplabv3、YOLOv8等智能算法对缺陷区域进行分割,进行阵列IRT分析,精度分别为95.8%、94.4%、94.1%。Efficient property-oriented design of composite layups via controllable latent features using generative VAEHuaixiang Sun, Xiaodong Wang, Jiaxue Li, Zengshan Li, Zhidong Guandoi:10.1016/j.compscitech.2024.110936 基于生成式VAE的可控潜在特征的高效面向属性的复合布局设计Fiber-reinforced composites provide substantial tailoring potential, while the extensive parameters and complex coupling mechanisms pose formidable challenges to layup designs. This paper presents an efficient inverse design framework for composite layups utilizing a variational autoencoder (VAE), which is applicable to non-conventional laminates. By leveraging the VAE's exceptional feature extraction and generative capabilities, the decoder rapidly produces layups with desired properties through controllable feature vectors. Based on the stacking characteristics of layups, multi-scale one-dimensional convolutions precisely extract sequence features relevant to mechanical properties and specific manufacturing constraints. A customized loss function is formulated to constrain the latent features, while addressing the non-uniqueness problem for layups with certain mechanical properties. The developed property-oriented VAE can generate 100,000 layups in seconds, achieving an average success rate of 66.9% under comprehensive in-plane and bending stiffness design, and remains effective for 100-ply thick laminate. For comparison, the VAE model outperforms the genetic algorithm and the logic-based method in reinforced panel designs, reducing the retrieval error by 46.4% and 38.1%, respectively. The proposed approach demonstrates flexible and efficient design advantages using generative machine learning models, and is easily extendable to other inverse design scenarios.纤维增强复合材料提供了巨大的定制潜力,但其广泛的参数和复杂的耦合机制给层合设计带来了巨大的挑战。本文提出了一种基于变分自编码器(VAE)的复合材料分层反设计框架,该框架适用于非常规层压板。通过利用VAE出色的特征提取和生成能力,解码器通过可控的特征向量快速生成具有所需属性的布局。多尺度一维卷积基于层叠材料的堆叠特性,精确提取与力学性能和特定制造约束相关的序列特征。提出了一种自定义的损失函数来约束潜在特征,同时解决了具有一定力学性能的铺层的非唯一性问题。开发的面向性能的VAE可在秒内生成10万层,在综合面内和弯曲刚度设计下平均成功率达到66.9%,并且对100层厚的层压板仍然有效。相比之下,VAE模型在加固板设计中优于遗传算法和基于逻辑的方法,检索误差分别降低了46.4%和38.1%。该方法利用生成式机器学习模型展示了灵活高效的设计优势,并且易于扩展到其他逆向设计场景。Anti-ballistic properties of hybrid UHMWPE fiber-reinforced composite armourJun Lin, Yongqiang Li, sheng Liu, Hualin Fandoi:10.1016/j.compscitech.2024.110941 超高分子量聚乙烯纤维增强复合装甲的抗弹道性能The ballistic performance of three hybrid composite plates, including ultra-high molecular weight polyethylene (UHMWPE), UHMWPE/Aramid, and UHMWPE/CFRP with similar surface density, was studied in the paper. These plates were tested under the impact of 7.62×25 mm full metal jacket (FMJ) bullets, with the dynamic back deformation (BFD) captured using Digital Image Correlation (DIC) technology. The effects of material combinations and striking faces on the dynamic response were discussed. The deformation and penetration mechanisms were analyzed using optical microscopy and micro-CT tomography. The results indicated that the UHMWPE/CFRP plate exhibited the lowest BFD, followed by UHMWPE and the UHMWPE/Aramid plate. When UHMWPE severed as the striking face, the fibers underwent through-thickness compression, which transitioned to in-plane tension and led to an elongated fracture of yarns. Similarly, Aramid fibers also experienced tensile fractures under similar conditions. In contrast, carbon fibers had brittle shear fractures when CFRP was the striking face. Additionally, the “V-shaped” cone traveling hinge velocity was calculated using DIC results, and the effects of the plate bending stiffness and wave impedance on protective performance were discussed. The findings emphasize the importance of an optimal material configuration to mitigate the propagation of compressive waves in the thickness direction and enhance bending stiffness, which is crucial for improving protection within ballistic limits.研究了具有相似表面密度的超高分子量聚乙烯(UHMWPE)、超高分子量聚乙烯/芳纶和超高分子量聚乙烯/CFRP三种杂化复合材料的弹道性能。这些板在7.62×25 mm全金属夹套(FMJ)子弹的冲击下进行了测试,并使用数字图像相关(DIC)技术捕获了动态背变形(BFD)。讨论了材料组合和冲击面对动态响应的影响。利用光学显微镜和微ct断层扫描分析了其变形和穿透机理。结果表明,UHMWPE/CFRP板的BFD性能最低,其次是UHMWPE和UHMWPE/芳纶板。当UHMWPE作为冲击面切断时,纤维受全厚压缩,由全厚压缩过渡为面内拉伸,导致纱线伸长断裂。同样,在相似的条件下,芳纶纤维也发生了拉伸断裂。CFRP为冲击面时,碳纤维发生脆性剪切断裂。此外,利用DIC计算结果计算了“v”形锥移动铰链速度,并讨论了板的弯曲刚度和波阻抗对保护性能的影响。研究结果强调了优化材料配置的重要性,以减轻压缩波在厚度方向上的传播,并提高弯曲刚度,这对于提高弹道极限内的保护至关重要。A superhydrophobic Fe3O4@MSN-PDMS based composite coating with icephobicity, long-term durability and self-healing property for anti-/de-icingLechun Deng, Zongwen Wang, Junzhi Wu, Xingshi Gu, Hao Yu, Yang Li, Yaru Cao, Fa Luo, Xianhu Liu, Qiang Chendoi:10.1016/j.compscitech.2024.110937 一种基于Fe3O4@MSN-PDMS的超疏水复合涂层,具有疏冰性、长期耐久性和自愈性,用于防/除冰Ice formation is a ubiquitous phenomenon in various fields and often leads to catastrophic consequence. Despite numerous anti-icing coating strategies have been exploited, there are still multiple roadblocks in the way of developing anti-icing coatings with durable and effective anti-/de-icing properties. In this work, Fe3O4 was coated in-situ with mesoporous silica nanoparticle (MSN), in which high dosage of polydimethylsiloxane (PDMS) was then loaded. As-obtained core-shelled Fe3O4@MSN-PDMS aggregates were incorporated into silicone resin to construct an NIR responsive anti-/de-icing coating via spraying method. The as-prepared coating exhibited superhydrophobicity (156.7 ° of water contact angle) and delayed icing to 412 s under -20 °C. Besides, the prepared coating could heat and release PDMS to constitute a PDMS/water double-layer lubricant under NIR irradiation, significantly reducing ice adhesion strength from 90.60 kPa to 12.04 kPa. Furthermore, the prepared coating demonstrates self-healing properties and high durability, releasing PDMS stored in the coating sustainably to heal the damaged coating surface and keeping superhydrophobicity after chemical etching and mechanical erosion. Finally, the de-icing applicability of the coating was validated using a homemade rotor wing model. Such core-shelled anti-/de-icing materials would provide theoretical basis and brand-new design strategy for development and application of anti-/de-icing materials.结冰是各个领域普遍存在的现象,往往会导致灾难性的后果。尽管已经开发了许多防冰涂层策略,但在开发具有耐用和有效防/除冰性能的防冰涂层的道路上仍然存在许多障碍。本研究采用中孔二氧化硅纳米颗粒(MSN)原位包覆Fe3O4,并在其表面负载高剂量的聚二甲基硅氧烷(PDMS)。将获得的核壳Fe3O4@MSN-PDMS骨料加入到有机硅树脂中,通过喷涂方法构建近红外响应的防/除冰涂层。制备的涂层具有超疏水性(156.7°的水接触角),在-20°C下延迟结冰至412 s。此外,制备的涂层在近红外照射下可以加热释放PDMS,形成PDMS/水双层润滑剂,冰的粘附强度从90.60 kPa显著降低到12.04 kPa。此外,制备的涂层具有自修复性能和高耐久性,可以持续释放涂层中储存的PDMS来修复受损的涂层表面,并在化学蚀刻和机械侵蚀后保持超疏水性。最后,利用自制的旋翼模型验证了涂层的除冰适用性。这种芯壳式防除冰材料将为防除冰材料的开发和应用提供理论依据和全新的设计策略。来源:复合材料力学仿真Composites FEM

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