今日更新：Composite Structures 2 篇，Composites Part A: Applied Science and Manufacturing 6 篇，Composites Part B: Engineering 7 篇，Composites Science and Technology 5 篇Composite StructuresDesign, modelling, and manufacturing of sandwich radome structure with out-of-band absorption and in-band transmission performancesJiaheng Yang, Huaibin Zheng, Yongqiang Pang, Bingyue Qu, Yongfeng Li, Jiafu Wang, Zhuo Xudoi:10.1016/j.compstruct.2024.118138具有带外吸收和带内传输性能的夹层天线罩结构的设计、建模和制造Muti-functional composite structures with customizable electromagnetic (EM) responses have attracted much interest in the radome field. In this study, a multi-layered foam-cored sandwich rasorber structure (FSRS) with absorption-transmission-absorption-type (A-T-A-type) of EM response was proposed. Silver-based frequency selective surface (FSS) screen and carbon-based film as alternatives for traditional metallized FSS and lumped resistors were integrated into the FSRS and prepared using a low-cost screen-printing method. Considering specific geometric and EM parameters, full-wave simulations were conducted to predict the EM characteristics of FSRS. Experimental findings demonstrated that under normal incidence, the absorption rate of the FSRS specimen in the frequency ranges of 3.2–6.4 GHz and 13.2–18 GHz is greater than 80 %, and the transmission rate in 9–11.3 GHz is greater than 80 %. Moreover, the absorption and transmission performances of the FRSR specimen remained stable under different polarization directions. The proposal may provide promising materials for future developments in low-observable radome technology.具有可定制电磁响应的多功能复合结构在天线罩领域引起了广泛的关注。本研究提出了一种具有吸收-透射-吸收(a -t -a)型电磁响应的多层泡沫芯夹层结构(FSRS)。将银基频率选择表面(FSS)和碳基薄膜作为传统金属化FSS和集总电阻的替代品集成到FSRS中，并使用低成本的丝网印刷方法制备。考虑特定的几何参数和电磁参数，进行了全波模拟，预测了FSRS的电磁特性。实验结果表明，在正常入射下，FSRS试样在3.2 ~ 6.4 GHz和13.2 ~ 18 GHz频率范围内的吸收率大于80 %，在9 ~ 11.3 GHz频率范围内的透射率大于80 %。此外，在不同偏振方向下，FRSR试样的吸收和透射性能保持稳定。该提案可能为未来低可观测天线罩技术的发展提供有前途的材料。Asymptotic homogenization for phase field fracture of heterogeneous materials and application to tougheningSen Liu, Shourong Hao, Yongxing Shendoi:10.1016/j.compstruct.2024.118134非均相材料相场断裂的渐近均匀化及其在增韧中的应用We propose an asymptotic homogenization framework to simulate the fracture of heterogeneous materials. This framework upscales the phase field model for microscale fracture and outputs anisotropic effective properties such as the degraded elasticity tensor and the fracture toughness. Furthermore, it quantitatively accounts for the toughening effect in a simple way. More specifically, when the critical energy release rate of a heterogeneous material is uniform, the framework reveals that toughening is essentially determined by the disparity of the toughnesses, the energy absorbed by the material before cracking.我们提出了一个渐近均质框架来模拟非均质材料的断裂。该框架扩展了微尺度断裂的相场模型，并输出了退化弹性张量和断裂韧性等各向异性有效特性。此外，它还以一种简单的方式定量地说明了增韧效果。更具体地说，当非均质材料的临界能量释放率是均匀的时，该框架揭示了增韧本质上是由韧性的差异决定的，即材料在开裂前吸收的能量。Composites Part A: Applied Science and ManufacturingOptimal utilization of waste wool: Preparation of bionic moisture-absorbing keratin membrane with hierarchical porous structure to harvest atmospheric moistureNing Zhang, Wenda Wang, Yipeng Zhang, Man Zhou, Ping Wang, Yuanyuan Yu, Qiang Wangdoi:10.1016/j.compositesa.2024.108209 废羊毛的优化利用:制备具有分层多孔结构的仿生吸湿角蛋白膜，收集大气中的水分In addressing the challenge of water scarcity, solar-assisted atmospheric water harvesting (SAWH) has emerged as a promising strategy. Here, we have designed a hierarchical regenerated wool keratin membrane (LiCl@CNMC) that mimics the natural Murray network. Carbon nano tube, serving as solar absorbers, are uniformly deposited on the hierarchical keratin membrane. Hygroscopic salt LiCl is impregnated into the keratin membrane to achieve exceptional water uptake capacity. Under simulated sunlight exposure, the surface temperature can reach 83.5 °C. Furthermore, the LiCl@CNMC membrane exhibits outstanding water absorption (0.79–2.67 g g−1) and desorption performance at 30 %-80 % RH. The bionic water-collecting membrane can carry out 12 adsorption–desorption cycles every day under outdoor conditions, and yielding 11.92 g g−1 day−1 of clean water. The design of regenerated keratin membrane not only provides a direct way for the regeneration and utilization of keratin materials, but also provides valuable guidance and inspiration for the preparation and application of natural polymers found.为了解决水资源短缺的挑战，太阳能辅助大气集水(SAWH)已经成为一种有前途的战略。在这里，我们设计了一种分层再生的羊毛角蛋白膜(LiCl@CNMC)，它模仿了天然的默里网络。碳纳米管作为太阳能吸收剂，均匀地沉积在分层角蛋白膜上。吸湿盐LiCl被浸渍到角蛋白膜中，以达到特殊的吸水能力。在模拟阳光照射下，表面温度可达83.5 °C。此外，LiCl@CNMC膜在30 %-80 % RH下表现出出色的吸水性能(0.79-2.67 g g−1)和解吸性能。在室外条件下，仿生集水膜每天可进行12次吸附-解吸循环，产生11.92 g g−1 day−1的洁净水。再生角蛋白膜的设计不仅为角蛋白材料的再生利用提供了直接途径，而且为所发现的天然聚合物的制备和应用提供了有价值的指导和启示。A novel P/Fe/Si-doped porphyrin with excellent flame retardancy and ultrastrong toughening effect on epoxy resinLian Yin, Jiale Zhang, Zhuoran Liang, Yongqian Shi, Kaihua Lu, Keqing Zhoudoi:10.1016/j.compositesa.2024.108210 一种新型的P/Fe/ si掺杂卟啉，具有优异的阻燃性和对环氧树脂的超强增韧作用Epoxy resin (EP) is one of the most versatile polymers. Nonetheless, its inherent flammability and brittleness severely limit its broad development. Moreover, existing additives make it difficult to meet the dual requirements of flame retardancy and toughening. Herein, a novel P/Fe/Si-doped porphyrin derivative (MTPD-Fe@SiO2) with nano-cauliflower structure was synthesized to develop advanced EP composites. MTPD-Fe@SiO2 exhibited good dispersion in EP matrix, which is attributed to the π-π interactions between the porphyrin and EP chains, as well as the mechanical interlocking of nano-cauliflower rough structure. Moreover, when 5 % of MTPD-Fe@SiO2 was incorporated, the tensile and flexural strengths of EP composites were increased by 48.1 % and 63.5 %, respectively, showing excellent toughening properties. Additionally, the maximum thermal degradation rate of EP/5 % MTPD-Fe@SiO2 was significantly reduced, indicating its superior thermal stability. Notably, compared with pure EP, the peak heat release rate and the peak smoke production rate of EP/5 % MTPD-Fe@SiO2 were decreased by 36.4 % and 43.6 %, while the residual char and limiting oxygen index increased to 30.9 % and 32.1 %, respectively. This was ascribed to the catalytic charring of transition metals and phosphates, the barrier effect of the solid carbon layer (Fe4(PO4)2O, SiO2), the trapping effect of phosphorus radicals and the dilution effect of incombustibles. This work provides a viable approach to solving the trade-off between refractoriness and mechanical performance.环氧树脂(EP)是用途最广泛的聚合物之一。然而，其固有的易燃性和脆性严重限制了其广泛发展。此外，现有添加剂难以满足阻燃和增韧的双重要求。本文合成了一种新型的P/Fe/ si掺杂卟啉衍生物(MTPD-Fe@SiO2)，具有纳米花椰菜结构，用于开发先进的EP复合材料。MTPD-Fe@SiO2在EP基体中表现出良好的分散性，这主要归因于卟啉与EP链之间的π-π相互作用，以及纳米花椰菜粗糙结构的机械互锁作用。当掺入5 %的MTPD-Fe@SiO2时，EP复合材料的拉伸强度和弯曲强度分别提高48.1% %和63.5 %，表现出优异的增韧性能。此外，EP/5的最大热降解率 % MTPD-Fe@SiO2显著降低，表明其具有较好的热稳定性。值得注意的是，与纯EP相比，EP/5 % MTPD-Fe@SiO2的峰值放热率和峰值产烟率分别降低了36.4% %和43.6% %，而残余焦和极限氧指数分别提高了30.9 %和32.1 %。这主要归因于过渡金属和磷酸盐的催化炭化、固体碳层(Fe4(PO4)2O、SiO2)的阻隔效应、磷自由基的捕获效应和不可燃物的稀释效应。这项工作为解决耐火度和力学性能之间的权衡提供了一种可行的方法。Silver nanowire bridged graphene framework for encapsulating phase change materials with high thermal conductivity and solar-to-heat conversion abilityHongli Cheng, Gaojie Han, Mengjie Su, Chengen He, Chuntai Liu, Yuezhan Fengdoi:10.1016/j.compositesa.2024.108207 银纳米线桥接石墨烯框架封装相变材料具有高导热性和太阳能-热转换能力To construct a high-efficiency thermally conductive graphene nanoplate (GNP) framework, ball-milling technique and silver nanowires (AgNW) bridging strategy were employed to improve the compatibility of GNP and the interfacial thermal resistance (ITR) in GNP skeletons, respectively. By using unidirectionally freeze casting technique, long range ordered GNP frameworks containing a small amount of AgNW as “bridge” were obtained, which were used to encapsulation phase change material (PCM). As a result, the honeycomb-like micropores of the framework with strong capillary effect give PCM anti-leakage and shape stability. The vertically aligned and AgNW bridged GNP skeletons form high-speed heat transfer paths endowith low ITR, thus significantly improve thermal conductivity to 7.24 W/mK. More importantly, GNP framework with strong light absorption ability endows PCM with well solar-to-heat conversion and storage ability. Therefore, AgNW bridged GNP framework endowing PCM with comprehensive thermal management ability exhibits a high potential in addressing the thermal problems of electronics.为了构建高效导热石墨烯纳米板(GNP)骨架，采用球磨技术和银纳米线(AgNW)桥接策略分别提高GNP骨架的相容性和界面热阻(ITR)。采用单向冷冻铸造技术，获得了包含少量AgNW作为“桥”的长距离有序GNP框架，用于封装相变材料(PCM)。结果表明，框架的蜂窝状微孔具有较强的毛细效应，使PCM具有抗泄漏性和形状稳定性。垂直排列和AgNW桥接的GNP骨架在低ITR下形成高速传热路径，从而显著提高导热系数至7.24 W/mK。更重要的是，具有强光吸收能力的GNP框架使PCM具有良好的光热转换和储存能力。因此，AgNW桥接GNP框架使PCM具有全面的热管理能力，在解决电子热问题方面显示出很大的潜力。Preparation and electromagnetic waves absorption performance of hibiscus-like CuS/SiC NWs@PANI in the GHz bandYanbin Zhang, Jian Wei, Xueting Li, Yi Yao, Wangwang Lei, Jiayi Hou, Kai Zhangdoi:10.1016/j.compositesa.2024.108208木槿样cu /SiC NWs@PANI在GHz波段的制备及其电磁波吸收性能With the increasing demand for electromagnetic (EM) waves absorbing materials in communication, military, and electronic devices, the exploration of lightweight, wideband, and highly absorptive materials in the GHz frequency range has become urgent. This article presents a successful synthesis of hibiscus-like copper sulfide (CuS)/silicon carbide nanowires (SiC NWs) @polyaniline (PANI) composite material using a combination of hydrothermal and in-situ polymerization techniques. With a filling amount of only 25 wt% of CuS/SiC NWs@PANI in the paraffin transmissive matrix, the material exhibits a minimum reflection loss (RLmin) of −31.6 dB at a thickness of 2.1 mm, while providing an effective absorption bandwidth (EAB) of 4.5 GHz. As the filling amount increases to 35 wt%, the RLmin drastically reduces to −41.38 dB at a thickness of 2.3 mm. The CuS particles exhibit a unique multi-layered asymmetric hibiscus-like structure, which greatly enhances the reflection of EM waves. The conductive polymer PANI, forming a coating layer at the interface with CuS and SiC NWs, effectively enhances the conductive loss. The collaborative interactions among the components in the ternary composite material significantly boost the EM waves absorption performance. This article offers valuable insights into the preparation and real-world application of absorbent materials with distinctive microstructures, thus opening up new avenues for the design of composite absorbing materials.随着通信、军事和电子设备对电磁吸波材料需求的不断增加，探索GHz频率范围内的轻质、宽带、高吸波材料已成为当务之急。采用水热和原位聚合相结合的方法成功合成了一种类似木芙蓉的硫化铜(cu)/碳化硅纳米线(SiC NWs) @聚苯胺复合材料。当石蜡透射矩阵中cu /SiC NWs@PANI的填充量仅为25 wt%时，该材料在2.1 mm厚度处的最小反射损耗(RLmin)为−31.6 dB，有效吸收带宽(EAB)为4.5 GHz。当填充量增加到35 wt%时，在厚度为2.3 mm时，RLmin急剧降低到- 41.38 dB。cu粒子呈现出独特的多层不对称木槿状结构，极大地增强了电磁波的反射。导电聚合物PANI在cu和SiC NWs界面处形成涂层，有效提高了导电损耗。三元复合材料中各组分之间的协同相互作用显著提高了材料的电磁波吸收性能。本文对具有独特微结构的吸波材料的制备和实际应用提供了有价值的见解，从而为复合吸波材料的设计开辟了新的途径。Manufacturing of thermoplastic composite sandwich panels using induction welding under vacuumR.G. Martin, C. Johansson, J.R. Tavares, M. Dubédoi:10.1016/j.compositesa.2024.108211真空感应焊热塑性复合材料夹芯板的制造A new method to manufacture thermoplastic composite sandwich panels is presented, making use of the induction welding process in which a magnetic susceptor generates the heat at the core/facesheet interface. This technique proposes a fast way to assemble thermoplastic sandwich structures without risking the deconsolidation of the composites skin. The welding pressure is obtained by applying vacuum over the sandwich panel. This vacuum induction welding method (Vac-IW) allows joining thermoplastic composite facesheets to a thermoplastic polymer core in a clean and non-contact manner. The feasibility of the method is demonstrated by preparing sandwich samples made of glass fibre reinforced polyetheretherketone (PEEK) skins and a 3D-printed polyetherimide (PEI) honeycomb core. A susceptor made of PEI and µm-sized nickel (Ni) particles is used to generate heat by magnetic hysteresis losses. The strength of the sandwich samples assembled by the Vac-IW method is evaluated by flatwise tensile (FWT) tests.提出了一种利用磁感应焊接工艺在芯/面界面处产生热量的热塑性复合材料夹芯板制造新方法。该技术提出了一种快速组装热塑性三明治结构的方法，而不会冒着复合材料皮肤解固化的风险。焊接压力是通过在夹芯板上施加真空来获得的。这种真空感应焊接方法(Vac-IW)允许以清洁和非接触的方式将热塑性复合材料表面连接到热塑性聚合物芯上。通过制备由玻璃纤维增强聚醚醚酮(PEEK)皮肤和3d打印聚醚酰亚胺(PEI)蜂窝芯制成的三明治样品，证明了该方法的可行性。由PEI和微米大小的镍(Ni)颗粒制成的感受器通过磁滞损失产生热量。通过平面拉伸(FWT)试验评估了用真空- iw方法组装的夹层样品的强度。Application of AIE luminogen-loaded core–shell fibers in self-warning and self-healing polymer coatings with enhanced corrosion resistanceXiaohong Ji, Jizhou Duan, Xia Zhao, Sepideh Pourhashem, Baorong Houdoi:10.1016/j.compositesa.2024.108213AIE载光素芯壳纤维在自预警自修复聚合物涂层中的应用Aggregation-induced emission (AIE) materials have been used for non-destructive visual detection of cracks and damages to prevent the final structural failure and increase the service life of coatings. In this study, a self-warning and self-healing core–shell fiber is synthesized for developing AIE composite coatings. In these core–shell fibers, a mixture of hmethylene diisocyanate (HDI) and tetraphenylethylene (TPE) is used as core constituent, and polyacrylonitrile (PAN) is used for preparing the shell, which are continuously wrapped with a high loading rate through coaxial electrospinning technology. The parameters of electrospinning process are optimized to achieve core–shell fibers with smooth surface and average diameter of 100 ± 50 nm. The composite coating reveals effective fluorescence in case of cracks in a corrosive environment. The maximum self-healing efficiency of the fiber coating is 94.8 % after soaking for 120 h. The introduced composite coating paves the way for improving the safety and reliability of critical engineering components.聚集致发射(AIE)材料已被用于裂纹和损伤的无损视觉检测，以防止结构最终破坏，提高涂层的使用寿命。本研究合成了一种自报警自修复的核壳纤维，用于发展AIE复合涂层。该纤维以二异氰酸酯(HDI)和四苯基乙烯(TPE)的混合物为芯材，以聚丙烯腈(PAN)为芯材，通过同轴静电纺丝技术连续包覆，具有较高的负载率。对静电纺丝工艺参数进行了优化，得到了表面光滑、平均直径为100 ± 50 nm的芯壳纤维。该复合涂层在腐蚀环境中即使出现裂纹也能显示出有效的荧光。浸泡120 h后，纤维涂层的最大自愈率为94.8 %。该复合涂层的引入为提高关键工程部件的安全性和可靠性铺平了道路。Composites Part B: EngineeringRoom temperature 3D printing of high-temperature engineering polymer and its nanocomposites with porosity control for multifunctional structuresHyun Chan Kim, Ruowen Tu, Henry A. Sodanodoi:10.1016/j.compositesb.2024.111444室温3D打印高温工程聚合物及其纳米复合材料的多孔性控制There is an increasing demand for the development of additive manufacturing techniques that support diverse materials with specific properties and performance characteristics. Engineering polymers are a type of high-performance material with lightweight, strong, and heat resistant. These properties enable replacing more dense materials, such as metals, and make them essential for application in various high-tech industries. Polyamide-imide (PAI) is an advanced engineering polymer with exceptional mechanical properties and thermal stability. However, due to the high glass transition temperature (Tg), the additive manufacturing of PAI 3D structures has not been realized through existing technologies. This study demonstrates room-temperature 3D printing for the PAI and PAI-based functional nanocomposite. Moreover, through a designed post-process drying procedure to control porosity, it is possible to enhance 3D structures' mechanical properties and functionality. The nanocomposite 3D systems exhibit a tensile strength of up to 105 MPa and Tg of 295 °C with aramid nanofibers, and an electrical conductivity of 200 S/m at 250 °C with carbon nanotubes. Given the high performance of printed nanocomposites with designed processes, we explore the potential and expended usage of more robust and lightweight polymer structures featuring diverse functionality for high-tech industries such as aerospace, air mobility, and semiconductor packaging.人们对开发支持具有特定属性和性能特点的各种材料的增材制造技术的需求日益增长。工程聚合物是一种具有轻质、高强度和耐热性能的高性能材料。这些特性可以取代金属等密度更大的材料，使其在各种高科技行业中得到广泛应用。聚酰胺-酰亚胺（PAI）是一种先进的工程聚合物，具有优异的机械性能和热稳定性。然而，由于玻璃化转变温度（Tg）较高，现有技术还无法实现 PAI 三维结构的增材制造。本研究展示了 PAI 和 PAI 基功能纳米复合材料的室温三维打印技术。此外，通过设计后处理干燥程序来控制孔隙率，还可以增强三维结构的机械性能和功能。使用芳纶纳米纤维的纳米复合三维系统的拉伸强度高达 105 兆帕，Tg 为 295 ℃；使用碳纳米管的纳米复合三维系统在 250 ℃ 下的导电率为 200 S/m。鉴于采用设计工艺打印的纳米复合材料的高性能，我们探索了更坚固、更轻的聚合物结构的潜力和用途，这些结构具有多种功能，可用于航空航天、空中交通和半导体封装等高科技行业。Highly conductive CFRP composite with Ag-coated T-ZnO interlayers for excellent lightning strike protection, EMI shielding and interlayer toughnessHuixin Zhu, Kunkun Fu, Tianlin Huang, Haiqing Liu, Bin Yang, Yuchen Zhou, Yan Lidoi:10.1016/j.compositesb.2024.111448 高导电性CFRP复合材料与镀银T-ZnO中间层，具有优异的雷击保护，电磁干扰屏蔽和中间层韧性Improvement of overall electrical conductivities of carbon fiber reinforced polymer (CFRP) composite is a novel protection strategy to prevent them against lightning strikes (LS) damage. In this article, conductive CFRP composites with silver/tetra-needle zinc oxide (Ag/T-ZnO) as interlayers for LS protection, electromagnetic interference (EMI) shielding and interlaminar toughness improvement were developed. The results showed that the Ag/T-ZnO interlayers created a three-dimensional conductive network inside the unidirectional (UD) CFRP laminates, leading to 229.7 and 22.44 times greater transverse and in-depth electrical conductivity than those of the pristine CFRP composites, respectively. The simulated LS experimental results demonstrated the LS protection effectiveness of the Ag/T-ZnO/CFRP composites under a lightning current with a peak of 100 kA. The EMI shielding effectiveness (SE) of UD Ag/T-ZnO/CFRP composites is 40.99 dB in the frequency range of 8.2∼12.4 GHz, 26.46 dB higher than that of the pristine composites due to the reflection loss at the Ag/T-ZnO interlayers. In addition, it was found that Mode I interlaminar toughness of the UD CFRP composites increased by 7.41% after the incorporation of the Ag/T-ZnO interlayers. This study provides an alternative strategy for designing LS protection and EMI shielding for aircraft.提高碳纤维增强聚合物(CFRP)复合材料的整体导电性是防止其遭受雷击损伤的一种新的保护策略。本文研究了以银/四针氧化锌(Ag/T-ZnO)为中间层的导电CFRP复合材料，用于LS保护、电磁干扰屏蔽和层间韧性增强。结果表明，Ag/T-ZnO夹层在单向CFRP复合材料内部形成了三维导电网络，其横向导电性和深度导电性分别是原始CFRP复合材料的229.7倍和22.44倍。模拟LS实验结果验证了Ag/T-ZnO/CFRP复合材料在峰值100ka雷电电流下的LS保护效果。在8.2 ~ 12.4 GHz频率范围内，UD Ag/T-ZnO/CFRP复合材料的电磁干扰屏蔽效能(SE)为40.99 dB，由于Ag/T-ZnO夹层处的反射损失，其屏蔽效能比原始复合材料高26.46 dB。Ag/T-ZnO夹层的加入使UD CFRP复合材料的I型层间韧性提高了7.41%。该研究为飞机的LS保护和EMI屏蔽设计提供了一种替代策略。The nucleation and growth mechanism of solid-state amorphization and diffusion behavior at the W-Cu interfaceKai Wang, Guoqing Yao, Mengwei Lv, Zumin Wang, Yuan Huang, Wei Xidoi:10.1016/j.compositesb.2024.111452 W-Cu界面固态非晶形核长大机理及扩散行为The W-Cu materials hold vast potential for applications in electronic information, nuclear energy, and aerospace sectors. Here, we report a new occurrence of solid-state amorphization on the Cu side near W-Cu interface. A potential function with accuracy close to density functional theory (DFT) is constructed using machine learning, while the atomic mechanism of solid amorphous nucleation and growth is unveiled through a combination of in-situ transmission electron microscopy (TEM) and molecular dynamics (MD) simulations. Our findings indicate that the Cu near W-Cu interface experiences an amorphous phase transition at 400 °C. This amorphous nucleation is linked to the stress coupling between the W-Cu interface and dislocations within Cu. The lattice distortion arising from dislocations, combined with interfacial stress, results in lattice twisting, leading to the formation of dislocation pileup, HCP and disordered structures. The results of the in-situ TEM show that the dislocation stacking and HCP structures exist for a short period of time, and these structures quickly turn into disordered structures, eventually forming an amorphous band with a width of about 8 nm at the W-Cu interface. However, the amorphous structure is unstable. As temperature rises, the amorphous structure undergoes recrystallization into an ordered structure. Furthermore, we investigated the atomic diffusion behavior of W-Cu. Simulation results reveal that the defect in W significantly impacts diffusion. In summary, our study provides theoretical support for the nucleation mechanism of solid-state amorphization, the understanding of interfacial stress-strain, and the application of W-Cu materials.钨铜材料在电子信息、核能和航空航天领域具有巨大的应用潜力。在这里，我们报道了在靠近W-Cu界面的Cu侧出现了新的固态非晶化现象。利用机器学习构建了精度接近密度泛函理论(DFT)的势函数，并结合原位透射电镜(TEM)和分子动力学(MD)模拟揭示了固体非晶态成核和生长的原子机制。我们的研究结果表明，在400°C时，W-Cu界面附近的Cu经历了非晶相变。这种非晶形核与W-Cu界面之间的应力耦合和Cu内部的位错有关。位错引起的晶格畸变，加上界面应力，导致晶格扭曲，从而形成位错堆积、HCP和无序结构。原位TEM结果表明，位错堆积和HCP结构在短时间内存在，这些结构迅速转变为无序结构，最终在W-Cu界面处形成宽度约为8 nm的非晶带。然而，非晶结构是不稳定的。随着温度的升高，非晶结构再结晶为有序结构。此外，我们还研究了钨铜的原子扩散行为。仿真结果表明，W的缺陷对扩散有显著影响。综上所述，本研究为固态非晶化成核机理、界面应力-应变的理解以及W-Cu材料的应用提供了理论支持。Non-Swelling Polyelectrolyte Complex Hydrogels with Tissue-matchable Mechanical Properties for Versatile Wet Wound ClosureXinyi Li, Jiarong Wang, Yirong Guo, Honglin Qian, Yiduo Chen, Yanchen Chen, Jing Wang, Youxiang Wang, M. Cristina L. Martins, Xinyang Hu, Jian’an Wang, Jian Jidoi:10.1016/j.compositesb.2024.111456具有组织匹配机械性能的非肿胀聚电解质复合水凝胶，用于多功能湿伤口闭合The stable adhesion of hydrogel-based bioadhesives with tissue-matchable mechanical properties in biological environments remains a significant challenge. In this work, we propose a polyethyleneimine-polyacrylic acid (PEI-PAA, PEA) double-network polyelectrolyte hydrogel with swelling resistant capacity and tunable mechanical properties via one-step UV-initiated polymerization. Driven by electrostatic interactions and polymer-chain entanglement, this PEA hydrogel displays a distinctive microphase separation behavior, which facilitates a wide tunability in mechanical properties. Specifically, the modulus varies from 0.4 MPa to 106 MPa, and the toughness ranges from 1479 kJ/m3 to 7641 kJ/m3, respectively. Besides, the microphase separation endows PEA hydrogel with notable anti-swelling properties in saline, TBS buffer, and blood, leading to consistent adhesion to diverse moist tissues. We further demonstrate that our PEA hydrogels provide matchable mechanical properties and long-lasting adhesion to rat skin and arteries, which promote skin injury healing and effectively halt artery rupture bleeding in vivo. This work presents a straightforward method to generate non-swelling hydrogels and offers novel insight into the development of bioadhesives to meet diverse mechanical requirements.具有组织匹配力学性能的水凝胶基生物胶粘剂在生物环境中的稳定粘附仍然是一个重大挑战。在这项工作中，我们提出了一种聚乙烯亚胺-聚丙烯酸(PEI-PAA, PEA)双网络聚电解质水凝胶，具有抗膨胀能力和可调的机械性能。在静电相互作用和聚合物链纠缠的驱动下，这种PEA水凝胶表现出独特的微相分离行为，从而促进了力学性能的广泛可调性。其中，模量为0.4 MPa ~ 106 MPa，韧性为1479 ~ 7641 kJ/m3。此外，微相分离使PEA水凝胶在生理盐水、TBS缓冲液和血液中具有显著的抗肿胀性能，从而与各种湿润组织保持一致的粘附。我们进一步证明，我们的PEA水凝胶具有与大鼠皮肤和动脉相匹配的力学性能和持久的粘附性，促进皮肤损伤愈合，有效地阻止动脉破裂出血。这项工作提出了一种生成非膨胀水凝胶的简单方法，并为生物粘合剂的发展提供了新的见解，以满足不同的机械要求。Pore evolution and mechanical response under locally varying density defects in ceramic matrix compositesChengyu Liang, Xiaojin Gao, Liang Fu, Hui Mei, Laifei Cheng, Litong Zhangdoi:10.1016/j.compositesb.2024.111459局部变密度缺陷下陶瓷基复合材料孔隙演化与力学响应Ceramic matrix composites have garnered significant attention in aerospace and other fields due to their outstanding properties. However, as a common and critical defect, density defect often results in non-uniform matrix distribution and internal pore formation, posing a substantial risk to component safety. This paper presents a novel method aimed at deliberately inducing varying degrees of density defects in SiCf/SiC. The feasibility of this method is validated using infrared thermography and computed tomography. As density defects aggravate, the porosity of the sample's defective region gradually increases, with both the number of micropores and the dimensions of larger pores expanding. This trend underscores the decreased compactness of the SiC matrix. Additionally, there is an initial decline in tensile strength followed by stabilization, while the tensile elastic modulus exhibits a continued decrease. The retention rates of the minimum tensile strength and tensile elastic modulus are 83.89 % and 64.77 %, respectively, compared to those of the defect-free samples. In terms of compressive properties, both compressive strength and compressive elastic modulus exhibit progressive decreases, culminating in final retention rates of 76.54 % and 72.02 %, respectively. Density defects reduce the matrix cracking stress and introduce new defects such as delamination, thereby altering the material's damage mechanism. This study provides innovative perspectives for risk assessment and lifespan prediction of density defects, especially concerning more complex components like turbine blades.陶瓷基复合材料以其优异的性能在航空航天等领域引起了广泛的关注。然而，密度缺陷作为一种常见和关键的缺陷，往往会导致基体分布不均匀和内部孔隙形成，对部件的安全构成重大风险。本文提出了一种新的方法，旨在故意诱导不同程度的密度缺陷的SiCf/SiC。利用红外热像仪和计算机断层扫描验证了该方法的可行性。随着密度缺陷的加剧，试样缺陷区的孔隙率逐渐增大，微孔的数量和较大孔隙的尺寸都在扩大。这种趋势强调了SiC基体致密性的降低。拉伸强度先下降后趋于稳定，拉伸弹性模量持续下降。与无缺陷试样相比，最小拉伸强度和拉伸弹性模量的保留率分别为83.89%和64.77%。在抗压性能方面，抗压强度和抗压弹性模量均呈递减趋势，最终保留率分别为76.54%和72.02%。密度缺陷降低了基体开裂应力，引入了分层等新的缺陷，从而改变了材料的损伤机制。该研究为密度缺陷的风险评估和寿命预测提供了创新的视角，特别是对于涡轮叶片等更复杂的部件。An ultrastrong wood-based phase change material for efficient photothermal conversion and thermal energy conservationChendong Qiu, He Jiang, Pengwei Liu, Chuanxi Jiang, Xianjun Ji, Yi Zhang, Weisheng Sun, Xi Guodoi:10.1016/j.compositesb.2024.111460一种具有高效光热转换和热能保存的超强木基相变材料Phase change material (PCM) with outstanding thermal energy storage and temperature regulation, holds tremendous interest in energy conservation and management. However, the application of conventional PCMs is limited due to issues of liquid leakage, poor mechanical properties, and insufficient photothermal conversion efficiency. In this work, inspired by the powerful muscle system, we developed a shape-stable PCM via in-situ polymerization of polyurethane in the wood. This wood-based PCM could reach a tensile strength of 96.5 MPa along the longitudinal direction, up to 3-50 times that of reported PCMs, due to a unique aligned fiber array and energy dissipation system. Meanwhile, this composite had a high enthalpy of 95.4 J/g and a photothermal conversion efficiency of 83.2%. It is believed that such an eco-friendly and ultrastrong wood-based PCM with efficient solar energy utilization will be a novel option for building energy collection, storage, and regulation.相变材料(PCM)以其优异的储热性能和温度调节性能，在能源节约和管理方面引起了人们极大的兴趣。然而，由于液体泄漏、机械性能差、光热转换效率不足等问题，传统pcm的应用受到限制。在这项工作中，受到强大的肌肉系统的启发，我们通过在木材中原位聚合聚氨酯开发了一种形状稳定的PCM。由于其独特的排列光纤阵列和能量耗散系统，该木材基PCM的纵向拉伸强度可达96.5 MPa，是现有PCM的3-50倍。同时，该复合材料具有95.4 J/g的高焓值和83.2%的光热转换效率。人们相信，这种具有高效太阳能利用的环保超强木基PCM将成为建筑能源收集、储存和调节的新选择。Importance of cohesive failure mode in fracture toughness enhancement of polymer nanocomposites with covalent grafting: A multiscale studyJihun Lee, Haolin Wang, Jae Hun Kim, Hyunseong Shindoi:10.1016/j.compositesb.2024.111462内聚破坏模式对共价接枝聚合物纳米复合材料断裂韧性增强的重要性:一项多尺度研究The covalent grafting between the nanoparticles and polymer matrix is considered a useful design factor to control the mechanical properties (e.g., fracture toughness). Meanwhile, in the theoretical viewpoint, the toughening mechanisms of the epoxy nanocomposites with covalent grafting are still unclear. In this study, a new multiscale fracture model is proposed to quantify the toughness enhancement of epoxy nanocomposites induced by the covalent grafting. Especially, it was concentrated on the investigation of the influences of the cohesive failure mode on the fracture toughness and revealed that the failure mode transition (from the adhesive failure mode to cohesive failure mode) near the nanoparticles with increasing grafting ratio is critical factor for the toughening mechanisms of the epoxy nanocomposites with covalent grafting. The theoretically derived multiscale model demonstrated that the cohesive failure mode significantly enhanced the fracture toughness of polymer nanocomposites by dissipating more energy compared to the adhesive failure mode. This study underscores the critical importance of rationally designing nanocomposites with an optimal grafting ratio that properly reflects the cohesive failure mode. It is anticipated that the multiscale analysis approach outlined in this study will provide valuable design guidelines and insights for polymer nanocomposites incorporating covalent grafting.纳米颗粒与聚合物基体之间的共价接枝被认为是控制机械性能(例如断裂韧性)的有用设计因素。同时，从理论角度来看，共价接枝环氧纳米复合材料的增韧机理尚不清楚。本文提出了一种新的多尺度断裂模型来量化共价接枝对环氧纳米复合材料韧性增强的影响。重点研究了内聚破坏模式对复合材料断裂韧性的影响，揭示了随着接枝率的增加，纳米颗粒附近从粘结破坏模式向内聚破坏模式的转变是影响共价接枝环氧纳米复合材料增韧机理的关键因素。理论推导的多尺度模型表明，黏合破坏模式比黏合破坏模式耗散更多能量，显著提高了聚合物纳米复合材料的断裂韧性。该研究强调了合理设计具有最佳接枝比的纳米复合材料的重要性，该接枝比适当地反映了内聚破坏模式。预计本研究中概述的多尺度分析方法将为包含共价接枝的聚合物纳米复合材料提供有价值的设计指南和见解。Composites Science and TechnologyBreathable, robust, and corrosion-resistant composite films with finger-web-like architecture for highly efficient electromagnetic interference shieldingJianqiao Wang, Lei Liu, Ze Wu, Youqiang Xing, Peng Huang, Bingjue Lidoi:10.1016/j.compscitech.2024.110603 透气，坚固，耐腐蚀的复合薄膜，具有指网状结构，用于高效的电磁干扰屏蔽Exploiting multifunctional electromagnetic shielding films is an inevitable requirement to address the complex usage environment and the advancement of flexible electronics. However, there are significant challenges in obtaining highly efficient electromagnetic shielding composites that possess both breathability, mechanical robustness, and corrosion resistance. Here, to overcome the constraints imposed by conventional dense composite films in engineering applications, we have devised an innovative composite film featuring a finger-web-like architecture comprised of metal fiber felt and Ti3C2Tx MXene. This structure provides a unique combination of air permeability, mechanical robustness, corrosion resistance, and superior EMI shielding capabilities. Utilizing nickel fiber felt (NF) as the substrate, NF/MXene/MnO2 (NMM) was obtained through facile self-assembly and reduction reaction. The maximum EMI shielding effectiveness of NMM reaches 87.3 dB and the absolute EMI shielding value is 3858 dB cm2 g–1, surpassing dense metal foils, as well as some typical foam and film structures. Meanwhile, by applying various metal fiber felt as substrates, different shielding films with performance bias can be obtained, demonstrating the universality of this strategy. The excellent breathability, mechanical robustness, and corrosion resistance enable NMM to cope with more demanding usage scenarios, particularly for the electromagnetic protection of marine equipment and various vents.开发多功能电磁屏蔽膜是解决复杂使用环境和柔性电子技术发展的必然要求。然而，在获得具有透气性、机械坚固性和耐腐蚀性的高效电磁屏蔽复合材料方面存在重大挑战。为了克服传统致密复合膜在工程应用中的局限性，我们设计了一种由金属纤维毡和Ti3C2Tx MXene组成的具有指网状结构的创新复合膜。这种结构提供了独特的透气性、机械坚固性、耐腐蚀性和卓越的电磁干扰屏蔽能力。以镍纤维毡(NF)为基材，通过简便的自组装和还原反应制得NF/MXene/MnO2 (NMM)。NMM的最大EMI屏蔽效能达到87.3 dB，绝对屏蔽值为3858 dB cm2 g-1，超过了致密金属箔以及一些典型的泡沫和薄膜结构。同时，采用不同的金属纤维毡作为衬底，可以得到不同的具有性能偏差的屏蔽膜，表明了该策略的通用性。优异的透气性、机械坚固性和耐腐蚀性使NMM能够应对更苛刻的使用场景，特别是船舶设备和各种通风口的电磁保护。Core-Sheath Smart Polymer Fiber Composites with High Elasticity and Thermal ConductivityZhan Sun, Huitao Yu, Can Chen, Mengmeng Qin, Wei Fengdoi:10.1016/j.compscitech.2024.110610 具有高弹性和导热性的芯-护套智能聚合物纤维复合材料Thermal conductive polymer fibers have broad development prospects because of its excellent thermal and mechanical properties. However, currently reported polymer fibers cannot simultaneously possess high thermal conductivity and high resilience, which greatly limits the application of thermal conductive polymer fibers. Therefore, preparing fibers with high thermal conductivity and high resilience is extremely challenging. The thermoplastic polyurethane/boron nitride liquid metal (TPU/BN-LMs) fiber with core sheath structure is prepared by coaxial wet spinning technology, the boron nitride (BN) doped in thermoplastic polyurethane elastomer (TPU) as sheath and the liquid metal (LMs) as core. The maximum tensile strength of the fiber is 3.9 MPa, and the elongation can reach 400%. After multiple cycles of stretching, it can return to its original state. In addition, the thermal conductivity of the fiber in the horizontal direction and the vertical direction are 10.0 W m-1 K-1 and 4.6 W m-1 K-1, respectively. This work solves the current problem of high thermal conductivity and high resilience of thermally conductive polymer fibers that are difficult to be compatible. And it provides a new research idea for the design and preparation of new high thermal conductivity and high resilience polymer fiber materials.导热聚合物纤维以其优异的热学性能和力学性能，具有广阔的发展前景。然而，目前报道的聚合物纤维不能同时具有高导热性和高回弹性，这极大地限制了导热聚合物纤维的应用。因此，制备具有高导热性和高回弹性的纤维是极具挑战性的。采用同轴湿纺丝技术，以氮化硼(BN)掺杂热塑性聚氨酯弹性体(TPU)为护套，液态金属(LMs)为芯芯，制备了具有芯芯护套结构的热塑性聚氨酯/氮化硼液态金属(TPU/BN-LMs)纤维。纤维的最大抗拉强度为3.9 MPa，伸长率可达400%。经过多次循环拉伸后，可以恢复到原来的状态。水平方向导热系数为10.0 W m-1 K-1，垂直方向导热系数为4.6 W m-1 K-1。本工作解决了目前导热聚合物纤维的高导热性和高回弹性难以兼容的问题。为新型高导热高回弹性高分子纤维材料的设计和制备提供了新的研究思路。Universal slope-based J-integral methods for characterization of the mode I, mode II and mixed mode I/II fracture behaviour of adhesively bonded interfacesFengzhen Sun, Maria Lißner, Nik Petrinic, Bamber R.K. Blackmandoi:10.1016/j.compscitech.2024.110611 基于斜率的通用j积分方法表征粘接界面的I型、II型和I/II混合模式断裂行为Universal slope-based J-integral methods have been developed for the determination of the energy release rate for adhesively bonded joints under mode I, mode II and mixed-mode (I/II) loading conditions. The individual J components corresponding to the mode I and mode II loading were separated based on the J-integral decomposition theory. The proposed methods use the slopes of the substrates at various locations to characterize the energy release rate and thus avoid the measurement of crack lengths, which are especially suitable for characterizing the tough interfaces associated with large fracture process zones ahead of crack tips. Under linear elastic deformation, the slope-based J equations were found to be equivalent to classical G equations based on linear elastic fracture mechanics (LEFM). Both experimental and numerical testing of adhesively bonded joints were undertaken to validate the slope-based J equations. The universal slope-based J-integral methods provide a reliable alternative to the measurement of G for adhesive joints or laminated composites undergoing nonlinear or inelastic deformations where conventional LEFM is not valid. It is shown that LEFM, even when coupled with an effective crack length approach, can be inaccurate when damage occurs in a test specimen away from the fracture process zone, as was seen here in mode II. Slope-based J equations can avoid these inaccuracies with a careful selection of contour paths. Slope based methods are therefore strong candidates for selection in future test standards for mode II fracture characterisation of structural adhesive joints.针对粘接接头在I型、II型和混合(I/II)加载条件下的能量释放速率，建立了基于斜率的通用j积分方法。基于J积分分解理论，分离了ⅰ型和ⅱ型荷载对应的J分量。所提出的方法使用基底在不同位置的斜率来表征能量释放率，从而避免了裂纹长度的测量，这特别适合表征与裂纹尖端前面的大断裂过程区相关的坚韧界面。在线弹性变形下，基于斜率的J方程等价于基于线弹性断裂力学的经典G方程。通过对粘接接头进行试验和数值测试，验证了基于斜率的J方程。对于经历非线性或非弹性变形的粘接接头或层合复合材料，传统的LEFM方法是无效的，通用的基于斜率的j积分方法为测量G提供了可靠的替代方法。结果表明，当损伤发生在远离断裂过程区的试样上时，即使结合有效的裂纹长度方法，LEFM也可能是不准确的，如图II模式所示。基于斜率的J方程可以通过仔细选择轮廓路径来避免这些不准确性。因此，在未来的测试标准中，基于边坡的方法是选择结构粘接接头II型断裂特征的有力候选者。Multi-scale "core-sheath" structure of electrospun veils to enhance the interlaminar fracture toughness and in-plane properties of CF/poly(phthalazinone ether ketone) laminatesYu Zhang, Xiaoliang An, Gang Zhao, Hang Jia, Yue Qiao, Hongjian Gu, Xi Chen, Wenqi Zhao, Yousi Chen, Xigao Jian, Cheng Liu, Zhihuan Wengdoi:10.1016/j.compscitech.2024.110612 采用多尺度“芯-鞘”结构的静电纺丝纱提高CF/聚酞嗪酮层合板的层间断裂韧性和面内性能Carbon fiber reinforced polymer laminates' weak interlaminar properties limit application in high load-bearing structural components. Interleaving electrospun polymer veils or nanofillers between layers has been shown to improve laminate interlaminar fracture toughness (ILFT). In this work, we constructed a "core-sheath" reinforced veil based on a bionic principle inspired by the "tree-root system" by combining ZnO nanowires with electrospun nanofibres to achieve uniform nanocomponent distribution and directional modulation. The effect of "core" structures with different thermal properties and "sheath" structures with different dimensions on the mode I and mode II interlaminar fracture toughness were investigated. It was found that mode I and mode II ILFTs impose different requirements on the interlaminar reinforcement structure due to the different loading modes. The intact nanofiber morphology and longer ZnO nanowires are more advantageous for mode I ILFT. Mode II ILFT, however, is more dependent on the adhesion of the reinforcing veil to the matrix. Mode I and mode II ILFTs values increased by up to 75.6% and 118%, respectively, when enhanced with suitable reinforcement veils.碳纤维增强聚合物层压板层间性能弱，限制了其在高承重结构构件中的应用。在层间穿插电纺丝聚合物薄膜或纳米填充物可提高层间断裂韧性。在这项工作中，我们基于受“树-根系统”启发的仿生原理，通过将ZnO纳米线与静电纺纳米纤维结合，构建了一个“核心-鞘”增强面纱，以实现纳米成分的均匀分布和方向调制。研究了不同热性能的“芯”组织和不同尺寸的“鞘”组织对I型和II型层间断裂韧性的影响。研究发现，由于加载方式的不同，I型和II型ilft对层间钢筋结构的要求不同。完整的纳米纤维形态和较长的ZnO纳米线对I模式ILFT更有利。然而，II型ILFT更依赖于增强膜对基体的粘附。模式I和模式II的ilft值分别增加了75.6%和118%。Spider silk inspired strong yet tough composite hydrogelsZhanqi Liu, Yichen Chu, Yongchuan Wu, Haidi Wu, Yahui Wang, Xiaohao Li, Ling Wang, Huaigui Xue, Yongqian Shi, Longcheng Tang, Pingan Song, Jiefeng Gaodoi:10.1016/j.compscitech.2024.110613 蜘蛛丝激发了坚韧的复合水凝胶Nanofillers are frequently used to improve the mechanical properties of hydrogels, but it is still difficult to develop composite hydrogels with simultaneously enhanced strength, fracture strain, toughness and fatigue threshold at a high water content. Inspired from the unique structure of spider silk, we propose a “macromolecular chain engineered aramid nanofiber (ANF) reinforcement” strategy to prepare strong and fatigue resistance hydrogels with a relatively high water content. ANFs can decrease the crystallinity while increase the stretchability of PVA hydrogels. The stress can be effectively transferred from the soft and ductile polymer chains to the hard and strong ANFs through strong interfacial hydrogen bonding. The tensile strength, fracture strain, toughness and fracture energy of ANF reinforced hydrogels (ARHs) can reach as high as 2.07 ± 0.15 MPa, 1084 ± 116%, 12.66 ± 1.1 MJ m-3, and 3196 ± 219 J m-2, respectively, at a water content of ∼ 80%. Also, ARHs show great crack propagation resistance with the fatigue threshold up to ∼ 157 J m-2. The bioinspired ARHs with outstanding mechanical properties and anti-swelling performance have promising applications in the field of soft underwater robots, artificial muscles, and so on.纳米填料被广泛用于改善水凝胶的力学性能，但在高含水量条件下，开发同时提高强度、断裂应变、韧性和疲劳阈值的复合水凝胶仍然很困难。受蜘蛛丝独特结构的启发，我们提出了一种“大分子链工程芳纶纳米纤维(ANF)增强”策略，以制备具有较高含水量的强抗疲劳水凝胶。ANFs可以降低聚乙烯醇水凝胶的结晶度，提高其拉伸性能。通过强大的界面氢键作用，应力可以有效地从柔软和延展性的聚合物链转移到坚硬和强的ANFs上。在水含量为80%时，ANF增强水凝胶(ARHs)的拉伸强度、断裂应变、韧性和断裂能分别高达2.07±0.15 MPa、1084±116%、12.66±1.1 MJ -3和3196±219 J -2。此外，ARHs具有良好的抗裂纹扩展能力，其疲劳阈值高达~ 157 J m-2。仿生ARHs具有优异的力学性能和抗膨胀性能，在水下软机器人、人造肌肉等领域具有广阔的应用前景。来源：复合材料力学仿真Composites FEM
