今日更新：Composite Structures 4 篇，Composites Part A: Applied Science and Manufacturing 2 篇，Composites Part B: Engineering 3 篇，Composites Science and Technology 1 篇Composite StructuresOptimization of stepped hole drilling for consistent aperture in BCF/PEEK and PEEK stacksYong Liu, Qixiu Han, Xiaojin Shi, Zitao Pan, Honggen Zhou, Yong Chendoi:10.1016/j.compstruct.2024.118212BCF/PEEK和PEEK叠层阶梯孔钻进一致孔径优化To ensure the aperture consistency of the stepped hole in the drilling of braided carbon fiber reinforced polyether ether ketone (BCF/PEEK) and PEEK stacks, a step variation parameter method is proposed to obtain the optimum process parameters in this study. Initially, the lay-up sequence is determined by analyzing diameter differences in drilled sequences of BCF/PEEK and PEEK stacks. Concurrently, hole-wall surface morphology and damage are observed under traditional drilling conditions to define stepped hole phenomena. Subsequently, optimum step position is identified by analyzing diameter differences at various positions with variable parameters. Moreover, the influence weight of drilling parameters on diameter difference is assessed using Taguchi orthogonal array. An optimization process scheme is proposed for minimum diameter difference control. Results suggest spindle speed of 2000 r/min and feed rate of 40mm/min for BCF/PEEK, and 5000 r/min and 30 mm/min for PEEK are optimum parameters. This method holds promise for achieving consistent apertures in other laminated composites during drilling.为了保证编织碳纤维增强聚醚醚酮(BCF/PEEK)和PEEK叠层在钻孔过程中台阶孔孔径的一致性，本研究提出了一种阶梯变化参数法，以获得最佳工艺参数。首先，通过分析BCF/PEEK和PEEK叠层的钻进序列的直径差异来确定叠层顺序。同时，在传统钻井条件下观察井壁表面形貌和损伤情况，定义阶梯孔现象。然后，通过分析变参数下各位置的直径差，确定最佳步进位置。此外，利用田口正交法评估了钻井参数权重对直径差的影响。提出了一种最小直径差控制的优化工艺方案。结果表明，BCF/PEEK的主轴转速为2000 r/min，进给速度为40mm/min, PEEK的主轴转速为5000 r/min，进给速度为30 mm/min。该方法有望在钻井过程中实现其他层压复合材料的一致孔径。Enhancing the flexural performance of concrete beams with 3D-printed UHP-SHCC permanent formwork via graded fiber volume fractionMinghong Qiu, Ye Qian, Jian-Guo Daidoi:10.1016/j.compstruct.2024.1182113d打印UHP-SHCC永久模板通过分级纤维体积分数提高混凝土梁的抗弯性能Conventional concrete structures often rely on labor-intensive and wasteful formwork systems. In contrast, 3D concrete printing (3DCP) technology offers a more efficient alternative for fabricating complex-shaped permanent formwork. This study fabricates innovative composite beams using 3D-printed ultra-high-performance strain-hardening cementitious composites (UHP-SHCC) as permanent formwork, followed by casting infill materials. The spatially tailored fiber dosage distribution in the 3D-printed UHP-SHCC permanent formwork enables the performance optimization of the composite beam. The flexural behavior of three such formed composite beams is evaluated using four-point bending tests. A reference beam with homogeneous fiber distribution in the UHP-SHCC formwork is also tested for comparison. The failure mode, overall load–displacement response, and cracking performance of four beams are comprehensively characterized and compared. The results reveal that employing graded fiber dosages in UHP-SHCC formwork enhances fiber efficiency and structural performance while reducing fiber usage and material costs. The use of 3D-printed UHP-SHCC formwork with graded fiber distribution, despite using 25% less fibers and reducing the material cost by 12.8%, leads to a 65.6% increase in strength and over 50% increase in energy absorption, or a 77.4% increase in ultimate displacement with comparable peak load to the reference beam with homogeneous fiber distribution.传统的混凝土结构往往依赖于劳动密集型和浪费的模板系统。相比之下，3D混凝土打印(3DCP)技术为制造复杂形状的永久模板提供了更有效的替代方案。本研究采用3d打印超高性能应变硬化胶凝复合材料(UHP-SHCC)作为永久模板，然后浇筑填充材料，制造创新型复合梁。3d打印UHP-SHCC永久模板中的空间定制纤维剂量分布使复合梁的性能得到优化。使用四点弯曲试验评估了三个这样的组合梁的抗弯性能。本文还对UHP-SHCC模板中纤维均匀分布的参考梁进行了对比试验。对四根梁的破坏模式、整体荷载-位移响应和开裂性能进行了综合表征和比较。结果表明，在UHP-SHCC模板中采用梯度纤维用量可提高纤维效率和结构性能，同时降低纤维用量和材料成本。使用梯度纤维分布的3d打印UHP-SHCC模板，尽管纤维用量减少了25%，材料成本降低了12.8%，但强度增加了65.6%，能量吸收增加了50%以上，与均匀纤维分布的参考梁相比，峰值荷载下的极限位移增加了77.4%。Entangled metallic porous material–silicone rubber interpenetrating phase composites with simultaneous high specific stiffness and energy consumptionXiaoyuan Zheng, Zhongmin Xiao, Zhiying Ren, Bao Zi, Yiwan Wu, Liming Yao, Hongbai Baidoi:10.1016/j.compstruct.2024.118213具有高比刚度和高能耗的金属多孔材料-硅橡胶互穿相复合材料High stiffness and superior energy consumption have consistently been primary research focuses in the field of damping materials. Hence, this work presented an innovative interpenetrating phase composite (IPC) crafted from wound elastic entangled metallic porous material and silicone rubber. The proposed composite effectively integrates the unique properties of the original materials, showcasing a seamless blend. Dynamic experimental tests were conducted to analyze the dynamic compression mechanical behavior of the composites, revealing that the composites exhibit excellent energy consumption capabilities and elevated stiffness characteristics. The improvement in both stiffness and damping characteristics is attributed to the addition of silicone rubber, which solidifies the structure of the composites. The introduction of interfacial friction results from maintaining compression, sliding, and other frictional interactions among the original spiral coils. Notably, the composites also display exceptional fatigue resistance. Overall, this work demonstrates the potential to concurrently achieve enhanced stiffness and superior energy consumption through the use of entangled metallic porous material and silicone rubber.高刚度和低能耗一直是阻尼材料领域的主要研究热点。因此，本研究提出了一种创新的互穿相复合材料(IPC)，该复合材料由缠绕弹性缠绕的金属多孔材料和硅橡胶制成。提议的复合材料有效地整合了原始材料的独特性能，展示了无缝融合。通过动态试验分析了复合材料的动态压缩力学性能，结果表明该复合材料具有优异的能耗性能和刚度提升特性。在刚度和阻尼特性的改善是由于硅橡胶的加入，它固化了复合材料的结构。界面摩擦的引入是由于原始螺旋线圈之间保持压缩、滑动和其他摩擦相互作用的结果。值得注意的是，复合材料还表现出优异的抗疲劳性能。总的来说，这项工作证明了通过使用缠绕金属多孔材料和硅橡胶同时实现增强刚度和优越能耗的潜力。Composites Part A: Applied Science and ManufacturingThe role of constitutive properties on the longitudinal compressive strength of compositesSoraia Pimenta, Mayank Patni, Dimitrios Bikos, Richard Traskdoi:10.1016/j.compositesa.2024.108264本构性能对复合材料纵向抗压强度的影响The longitudinal compressive strength of fibre–reinforced composites is often a limiting factor for structural design. This paper uses micromechanical finite–element analyses to examine how the constitutive properties of the matrix, fibres, and interface affect the composite’s strength. For a typical carbon/epoxy composite, the matrix shear strength has a larger effect than the modulus; a linear–elastic perfectly–plastic approximation of the matrix shear curve may overestimate the composite’s strength by over 15%. A pressure–dependent and dilatant matrix plasticity response may strengthen the composite by 30%, considering current uncertainties in friction and dilation angles of epoxy matrices. The finite shear modulus of carbon fibres may weaken the composite by more than 10%. Considering a cohesive interface using traction–separation laws significantly affects the predicted response of the composite, even for interfaces stronger than the matrix. Opportunities for improving the characterisation, modelling and performance of the constituents in terms of matrix plasticity, fibre shear modulus, and interface response are discussed.纤维增强复合材料的纵向抗压强度往往是结构设计的限制因素。本文使用微力学有限元分析来研究基体、纤维和界面的本构特性如何影响复合材料的强度。对于典型的碳/环氧复合材料，基体抗剪强度的影响大于模量;矩阵剪切曲线的线弹性完全塑性近似可能会将复合材料的强度高估15%以上。考虑到当前环氧基摩擦角和膨胀角的不确定性，压力相关和膨胀的基体塑性响应可以使复合材料的强度提高30%。碳纤维的有限剪切模量会使复合材料的强度降低10%以上。使用牵引分离定律考虑内聚界面会显著影响复合材料的预测响应，即使对比基体强的界面也是如此。讨论了在基体塑性、纤维剪切模量和界面响应方面改进表征、建模和性能的机会。Double percolation approach for hybrid graphene Nanoplatelet-Carbon black nanocomposites based on electrical impedance SpectroscopyX.F. Sánchez-Romate, A. Jiménez-Suárez, J.M. Sanz-Ayet, V. García-Martínez, M.R. Gude, S.G. Prolongodoi:10.1016/j.compositesa.2024.108273基于电阻抗谱的石墨烯纳米板-炭黑复合材料双渗透研究A double-percolation model for predicting electrical properties in hybrid carbon black (CB)-graphene nanoplatelet (GNP) nanocomposites is proposed. This model is based on DC and EIS measurements. From DC measurements, a non-ohmic behavior is observed for low-filled nanocomposites whereas at high-filled ones, an ohmic behavior is noticed. From EIS analysis, the behavior of the system can be modeled by an equivalent circuit formed by a series of inductance-resistance capacitance (LRC), for contact and intrinsic electrical mechanisms, and resistance–capacitance (RC) elements, for tunneling transport, where the capacitances are substituted by Constant Phase Elements (CPEs) due to the presence of scattering effects. The complex impedance analysis shows a GNP-dominated electrical behavior at a high CB/GNP ratio. At a medium CB/GNP ratio a double percolating network is formed. At a low CB/GNP ratio, the electrical transport is CB-dominated. The proposed model based on the classical percolation theory with a double threshold properly fits the electrical measurements.提出了一种预测炭黑(CB)-石墨烯纳米板(GNP)复合材料电性能的双渗透模型。该模型基于直流和EIS测量。从直流测量中，观察到低填充纳米复合材料的非欧姆行为，而在高填充纳米复合材料中，观察到欧姆行为。从EIS分析来看，系统的行为可以用一个等效电路来建模，该等效电路由一系列电感-电阻电容(LRC)组成，用于接触和固有电机制，电阻-电容(RC)元素组成，用于隧道输运，其中由于散射效应的存在，电容被恒相元件(cpe)取代。复杂阻抗分析表明，在高CB/GNP比下，GNP主导的电行为。在中等CB/GNP比率时，形成双重渗透网络。在低CB/GNP比率下，电输运以CB为主。基于经典渗流理论的双阈值模型较好地拟合了电测量结果。Composites Part B: EngineeringHigh strength and ductility high-entropy intermetallic matrix composites reinforced with in-situ hierarchical TiB2 particlesZhen Hu, Hao Dong, Yongkun Mu, Caitao Fan, Yandong Jia, Jingli Ren, Anzhou Qi, Gang Wangdoi:10.1016/j.compositesb.2024.111556 原位分层TiB2颗粒增强高强延展性高熵金属间基复合材料The design guided by entropy enables the attainment of superior mechanical properties and further extends the concept of high-entropy alloys to intermetallic systems, thus forming high-entropy intermetallic compounds and even high-entropy intermetallic matrix composites. In this study, a novel high-entropy intermetallic matrix composites incorporating in-situ hierarchical TiB2 particles was successfully synthesized through the spark plasma sintering. This method enables precise control over the microstructure, ensuring uniform distribution of the in-situ formed TiB2 particles within the high-entropy intermetallic matrix. The in-situ formation of TiB2 particles is achieved through a reactive sintering mechanism, which not only contributes to the composite's enhanced mechanical properties but also ensures excellent bonding between the precipitates and intermetallic matrix. The composites were composed of the ordered L12 intermetallic matrix and the hierarchical hexagonal-close-packed TiB2 particles. Due to the L12 intermetallic matrix and the heterogeneous distribution of TiB2 reinforcement, the intermetallic matrix composites demonstrate a high ultimate tensile strength of ∼1400 MPa. The TiB2 play a pivotal role in impeding the propagation of cracks and the collaborate with distinctive disordered interfaces at grain boundaries, ensuring enough ductility. The disordered interfaces, exhibiting an average width in the range of 5 nm to 10 nm, possess the capability to delay fracture and promote the strain-hardening rate during plastic deformation. The intermetallic matrix composites overcome the limitations typically associated with conventional intermetallics and offer an excellent strength and ductility balance. These findings are expected to formulate additional strategies for designing in-situ reinforcement-strengthened high-entropy intermetallic matrix composites with exceptional mechanical properties.以熵为指导的设计可以获得优异的力学性能，并将高熵合金的概念进一步扩展到金属间体系，从而形成高熵金属间化合物甚至高熵金属间基复合材料。在本研究中，通过火花等离子烧结成功合成了一种含有原位分层TiB2粒子的新型高熵金属间基复合材料。该方法能够精确控制微观结构，确保原位形成的TiB2颗粒在高熵金属间基质中的均匀分布。TiB2颗粒的原位形成是通过反应烧结机制实现的，这不仅有助于增强复合材料的力学性能，而且还确保了析出物与金属间基体之间的良好结合。该复合材料由有序的L12金属间基和层次化的六边形密排TiB2颗粒组成。由于L12金属间基和TiB2增强体的非均匀分布，金属间基复合材料的抗拉强度高达1400 MPa。TiB2在阻止裂纹扩展和与晶界处独特的无序界面协同作用方面起着关键作用，从而保证了足够的延展性。无序界面的平均宽度为5 ~ 10 nm，在塑性变形过程中具有延迟断裂和提高应变硬化速率的作用。金属间基复合材料克服了传统金属间基复合材料的局限性，并提供了良好的强度和延展性平衡。这些发现有望为设计具有优异力学性能的原位增强高熵金属间基复合材料制定额外的策略。Enhanced osteogenesis and inflammation suppression in 3D printed n-HA/PA66 composite scaffolds with PTH(1-34)-loaded nPDA coatingsZhimou Zeng, Linnan Wang, Bo Qu, Xingyu Gui, Boqing Zhang, Zhipeng Deng, Yuxiang Qin, Zhuangzhuang Li, Qiujiang Li, Lei Wang, Yujiang Fan, Changchun Zhou, Yueming Songdoi:10.1016/j.compositesb.2024.111566PTH(1-34)负载nPDA涂层3D打印n-HA/PA66复合支架增强成骨和炎症抑制In current clinical applications, spinal fusion predominantly are mostly inertness biomaterials with dense structures, which restrict the interface for new bone growth and impede the formation of interlocking structures, thereby caused failed bone integration. To address these challenges, this research proposed a novel 3D printed nano-hydroxyapatite/polyamide66 (n-HA/PA66) composited biological scaffold. Fused Deposition Modeling (FDM) technology was used to fabricate optimized porous architecture scaffold with balanced mechanical properties. A coating of polydopamine nanoparticles (nPDA) loaded with Parathyroid Hormone (PTH) (1-34) was then prepared on the scaffold surface, it effectively mitigated the inflammatory response and enhancing bone integration. In vitro results indicated a sustained release of PTH (1-34) would promote the osteogenic ability of scaffold. In vivo results demonstrated that the composited biological scaffold exhibited good ability to induce bone tissue regeneration which is beneficial for spinal fusion applications.在目前的临床应用中，脊柱融合主要采用结构致密的惰性生物材料，这些材料限制了新骨生长的界面，阻碍了联锁结构的形成，导致骨融合失败。为了解决这些挑战，本研究提出了一种新型3D打印纳米羟基磷灰石/聚酰胺66 (n-HA/PA66)复合生物支架。采用熔融沉积建模(FDM)技术制备力学性能平衡的多孔支架。然后在支架表面制备负载甲状旁腺激素(PTH)(1-34)的聚多巴胺纳米颗粒(nPDA)涂层，它有效地减轻了炎症反应，增强了骨整合。体外实验结果表明，PTH(1-34)的持续释放可促进支架的成骨能力。体内实验结果表明，复合生物支架具有良好的诱导骨组织再生能力，有利于脊柱融合应用。Flexible, superhydrophobic, and self-cleaning rGO/LDH/PPy-modified fabric for full X-band electromagnetic wave absorptionYaxin Meng, Zhong Zhang, Xiao Wang, Xianguang Hou, Tian Wang, Xiaoqing Guo, Xuqing Liu, Mingwei Tian, Lijun Qu, Lili Wang, Xiansheng Zhangdoi:10.1016/j.compositesb.2024.111572 柔性，超疏水，自清洁的rGO/LDH/ py改性织物，用于全x波段电磁波吸收High-performance flexible microwave absorbing textiles are the subject of a research boom due to the growing need for flexible wearable electronic gadgets that can withstand electromagnetic wave pollution and operate in challenging situations. Herein, we combine the two techniques of thermal reduction and in-situ growth to produce a reduced graphene oxide /FeCo-layered double hydroxide/polypyrrole (rGO/LDH/PPy) coated fabric with good superhydrophobic qualities and high electromagnetic wave absorption (EWA) performance. rGO/LDH and PPy work together to generate a multidimensional heterostructure, which offers the coated fabric a high electromagnetic loss capacity. The coating design uses a fluffy and complicated aramid fabric as the skeleton. The impedance gradient may be created to modify the fabric's ability to absorb electromagnetic waves by varying the concentration of Py. A full coverage of the X-band can be achieved by the coated fabric, which has an RLmin of -45.0 dB and a thickness of 3.5 mm. The layered rough structure generated by PPy, FeCo-LDH, and rGO in conjunction with the low surface energy material SN-67 results in an exceptional superhydrophobic property with a WCA of 156.9° for the coated fabric. Furthermore, this rGO/LDH/PPy coated fabric is robust and does not lose its superhydrophobicity even after repeated tape stripping, extended chemical exposure, and high and low temperature conditions. This work indicates potential application value for flexible electromagnetic wave-absorbing materials that maintain high efficiency in challenging situations, and it offers a solid foundation for the design of multifunctional EWA materials based on textiles.高性能柔性微波吸收纺织品是研究热潮的主题，因为对柔性可穿戴电子设备的需求日益增长，这些电子设备可以承受电磁波污染并在具有挑战性的情况下运行。本文将热还原和原位生长两种技术相结合，制备了一种具有良好超疏水性和高电磁波吸收性能的还原氧化石墨烯/ feo层状双氢氧化物/聚吡咯(rGO/LDH/PPy)涂层织物。rGO/LDH和PPy共同作用产生多维异质结构，这为涂层织物提供了高电磁损耗能力。涂层设计使用蓬松复杂的芳纶织物作为骨架。阻抗梯度可以通过改变Py的浓度来改变织物吸收电磁波的能力。该涂层织物的RLmin为-45.0 dB，厚度为3.5 mm，可实现对x波段的完全覆盖。由PPy、feo - ldh和rGO生成的层状粗糙结构与低表面能材料SN-67结合，使涂层织物具有优异的超疏水性能，WCA为156.9°。此外，这种rGO/LDH/PPy涂层织物坚固耐用，即使在反复剥离胶带，长时间化学暴露以及高温和低温条件下也不会失去其超疏水性。研究结果表明，柔性电磁波吸波材料具有潜在的应用价值，可在复杂环境下保持高效，为基于纺织品的多功能电磁吸波材料的设计提供了坚实的基础。Composites Science and TechnologyEnhanced thermal conductivity of CS/BN/Ti3O5 coatings to promote electron transport for ultra-sensitive fire sensingSijia Sun, Shuai Zhang, Mingzhu Pandoi:10.1016/j.compscitech.2024.110664 CS/BN/Ti3O5涂层热导率的提高促进了超灵敏火灾传感中的电子传递Intelligent fire warning system is a crucial protective equipment reduce fire hazards. A recent increasing concern is the development of sensitive fire warning materials that can be integrated with combustible materials to provide real-time alarms in the fire. However, current research on improving the sensitivity of fire warning sensors based on temperature-resistance response focuses on constructing continuous conductive networks. The effect of the heat transfer process is ignored, which limits the further improvement of alarm sensitivity. Here, we developed a strategy to improve thermal conductivity. Based on the chitosan (CS) conductive network in Ti3O5-based fire sensing system, aminated 2D h-BN nanosheets with high temperature resistance and ultrahigh in-plane thermal conductivity were further introduced. The h-BN improves the thermal conductivity of the fire warning coating from 1.43 W/m·K to 2.29 W/m·K. Intelligent fire warning sensors with ultra-sensitivity (1.16 s), low response temperature (170 oC), duration time (12 min) and durability (100 cycles) were successfully prepared by improving thermal conductivity to rapidly transfer heat to Ti3O5, which leads to a rapid decrease in resistance as the core mechanism. This work proposed an ingenious strategy for the construction of high fire safety and thermal conduction fireproof coatings, which revealed enticing prospects in the field of intelligent coatings.智能火灾报警系统是减少火灾危险的重要防护设备。最近越来越受关注的是开发敏感的火灾报警材料，可以与可燃材料相结合，在火灾中提供实时报警。然而，目前基于温度电阻响应提高火灾报警传感器灵敏度的研究主要集中在构建连续导电网络上。忽略了传热过程的影响，限制了报警灵敏度的进一步提高。在这里，我们开发了一种改善导热性的策略。在ti3o5基火灾传感系统中壳聚糖(CS)导电网络的基础上，进一步研究了具有耐高温、超高面内导热性能的胺化二维h-BN纳米片。h-BN使火灾报警涂层的导热系数由1.43 W/m·K提高到2.29 W/m·K。通过提高导热系数，将热量快速传递给Ti3O5，从而以电阻快速降低为核心机制，成功制备出超灵敏度(1.16 s)、低响应温度(170 oC)、持续时间(12 min)和耐久性(100次循环)的智能火灾报警传感器。本工作为构建高防火安全性和导热性防火涂料提出了一种巧妙的策略，在智能涂料领域显示出诱人的前景。来源：复合材料力学仿真Composites FEM
