今日更新：Composites Part A: Applied Science and Manufacturing 1 篇，Composites Part B: Engineering 4 篇，Composites Science and Technology 2 篇Composites Part A: Applied Science and ManufacturingSynergetic improvement of dielectric properties and thermal conductivity in Zn@ZnO/carbon fiber reinforced silicone rubber dielectric elastomersFang Wang, Wenying Zhou, Yingfei He, Yajuan Lv, Ying Wang, Zijun Wangdoi:10.1016/j.compositesa.2024.108129协同改善 Zn@ZnO/碳纤维增强硅橡胶介电弹性体的介电性能和导热性能Dielectric elastomers (DEs) with large dielectric permittivity (ε') but low loss, high thermal conductivity (TC), are highly pursued in artificial muscles. To elevate the ε' and TC of raw zinc (Zn)/silicone rubber (SR), raw Zn particles were oxidized to Zn@ZnO (zinc oxide), and then incorporated into SR. Compared to raw Zn/SR, the Zn@ZnO/SR showcases the enhanced ε' and TC because the ZnO interlayer induces intraparticle polarization and promotes interfacial phonon transport. Further, synergetic improvement of ε' and TC is found when modicums carbon fibers (CF) was added into Zn@ZnO/SR. The ε' and TC of Zn@ZnO/CF/SR are 23.83 and 1.53 W/(m·K), corresponding to 3.41 and 0.48 W/(m·K) for raw Zn/SR at 60 phr fillers. However, dielectric loss and electric conductivity of Zn@ZnO/CF/SR are remained at low levels. This work provides a strategy for design and preparation of robust SR DEs with high ε' and TC but low loss for prospective applications.具有大介电常数（ε'）、低损耗和高导热率（TC）的介电弹性体（DE）在人造肌肉中备受追捧。为了提高生锌（Zn）/硅橡胶（SR）的ε'和热导率，将生锌颗粒氧化成 Zn@ZnO（氧化锌），然后加入到硅橡胶中。与未加工的 Zn/SR 相比，Zn@ZnO/SR 的ε'和 TC 均有所提高，这是因为 ZnO 中间层诱导了粒子内极化，促进了界面声子传输。此外，在 Zn@ZnO/SR 中加入模数碳纤维（CF）后，ε'和 TC 也得到了协同改善。Zn@ZnO/CF/SR 的ε'和 TC 分别为 23.83 W/(m-K) 和 1.53 W/(m-K)，而原始 Zn/SR 在 60 phr 填料条件下的ε'和 TC 分别为 3.41 W/(m-K) 和 0.48 W/(m-K)。然而，Zn@ZnO/CF/SR 的介电损耗和电导率仍处于较低水平。这项工作为设计和制备具有高ε'和高导电率但低损耗的稳健型 SR DEs 提供了一种策略，具有广阔的应用前景。Composites Part B: EngineeringResolving engineering challenges: Deep learning in frequency domain for 3D inverse identification of heterogeneous composite propertiesYizhe Liu, Yue Mei, Yuli Chen, Bin Dingdoi:10.1016/j.compositesb.2024.111353解决工程难题：频域深度学习用于异质复合材料特性的三维逆向识别The inverse identification of heterogeneous composite properties from measured displacement/strain fields is pivotal in engineering. Traditional methodologies and emerging machine learning techniques both confront two major challenges. The first challenge involves achieving rapid identification while maintaining robustness to noise or pollution, and the second pertains to applicability in resolving complex three-dimensional (3D) engineering problems. To address these issues, a novel deep learning in frequency domain method (DLfd) for 3D inverse identification is proposed. Utilizing 3D-discrete cosine transform (3D-DCT), this method reduces input dimension by 98.24%, thereby simplifying the 3D problem to a computationally manageable form. A subsequent U-Net model establishes high-precision mappings between the reduced 3D-DCT coefficients of strain fields and modulus field, and the L1-error for the predicted modulus field is remarkably low at 2.431%. Even facing large noise (5% level) interference, the L1-error increases only 0.1%, demonstrating the robustness of the method. Coupled with Bayesian optimization, DLfd can generate accurate predictions even with incomplete measurements, and has been validated through several case studies involving measured fields missing in various shapes and locations. The method demonstrates general applicability to both 2D and 3D scenarios, and effectively mitigates the challenges posed by noise and data pollution, bringing it a step closer to practical implementation.从测量到的位移/应变场反向识别异质复合材料的特性在工程学中至关重要。传统方法和新兴的机器学习技术都面临着两大挑战。第一个挑战是实现快速识别的同时保持对噪声或污染的鲁棒性，第二个挑战是解决复杂的三维（3D）工程问题的适用性。为解决这些问题，我们提出了一种用于三维逆向识别的新型频域深度学习方法（DLfd）。利用三维离散余弦变换（3D-DCT），该方法将输入维度减少了 98.24%，从而将三维问题简化为可计算的形式。随后的 U-Net 模型在缩小后的应变场 3D-DCT 系数和模量场之间建立了高精度映射，预测模量场的 L1 误差非常低，仅为 2.431%。即使面对较大的噪声（5% 水平）干扰，L1-误差也仅增加 0.1%，证明了该方法的鲁棒性。DLfd 与贝叶斯优化相结合，即使在测量结果不完整的情况下也能得出准确的预测结果，并通过涉及各种形状和位置的测量场缺失的多个案例研究得到了验证。该方法展示了对二维和三维场景的普遍适用性，并有效缓解了噪声和数据污染带来的挑战，使其离实际应用更近了一步。Hollow spherical SiC@Ni composites towards the tunable wideband electromagnetic wave absorptionJinyan Wang, Jintang Zhou, Van Zalinge Harm, Zhengjun Yao, Li Yangdoi:10.1016/j.compositesb.2024.111361实现可调宽带电磁波吸收的中空球形 SiC@Ni 复合材料Combining dielectric substrates and magnetic materials is a practical approach to improve electromagnetic wave (EMW) absorption performance due to the dielectric and magnetic synergy loss effect. In this work, uniform monodisperse hollow SiC@Ni (H–SiC@Ni) composites were synthesised through a simple route, including the sacrificial templating method and the subsequent reduction reaction. Different contents of Ni3S2 and Ni could be obtained by adjusting the volume and reaction temperature, which are closely related to the electromagnetic parameters and absorption capabilities. The results show that the H–SiC@Ni-750 composite reaches the optimum EMW absorption performance with the minimum reflection loss of −55.7 dB at 7.3 GHz and the effective absorption bandwidth (EAB) of 8.8 GHz at 2.6 mm. The high absorption performance of the H–SiC@Ni-750 composite benefits from the synergistic dielectric loss and magnetic loss of SiC and Ni nanoparticles. In addition, the hollow and monodisperse core-shell structure of the samples can increase the transmission path through multiple reflections and scattering and further dissipate the EMW energy. This work provides a facile pathway to prepare H–SiC@Ni composite with broadband electromagnetic absorption performance.由于电介质和磁性材料的协同损耗效应，将电介质基底和磁性材料相结合是提高电磁波（EMW）吸收性能的一种实用方法。本研究通过牺牲模板法和随后的还原反应等简单路线合成了均匀的单分散空心 SiC@Ni（H-SiC@Ni）复合材料。通过调节与电磁参数和吸收能力密切相关的体积和反应温度，可获得不同含量的 Ni3S2 和 Ni。结果表明，H-SiC@Ni-750 复合材料达到了最佳电磁波吸收性能，在 7.3 GHz 时的反射损耗最小为 -55.7 dB，在 2.6 mm 时的有效吸收带宽（EAB）为 8.8 GHz。H-SiC@Ni-750 复合材料的高吸收性能得益于 SiC 和 Ni 纳米颗粒的介电损耗和磁损耗的协同作用。此外，样品的中空和单分散核壳结构可通过多次反射和散射增加传输路径，并进一步耗散电磁波能量。这项工作为制备具有宽带电磁吸收性能的 H-SiC@Ni 复合材料提供了一条简便的途径。Bio-based flame retardant for manufacturing fire safety, strong yet tough versatile epoxy resinJiahui Li, Qi Cao, Yi Zhao, Chengwen Gu, Beitao Liu, Qianqian Fan, Cijian Zhang, Yu Huang, Shuzi Jiang, Xigao Jian, Zhihuan Wengdoi:10.1016/j.compositesb.2024.111362 生物基阻燃剂可确保制造过程中的防火安全，是强韧而坚固的多功能环氧树脂Bio-based flame retardants have attracted growing attention for sustainability and comparable efficiency to petroleum-based counterparts but suffer from compatibility issues with epoxy resins and the trade-off between strength and toughness. Here, a Schiff base-derived phosphorus-based flame retardant (TV-DOPO) was developed from biobased vanillin and tyramine. In the presence of the binary curing agents, nanoscale in-situ constructive phase separation induced by hierarchical thermal curing process and strong hydrogen bonding provide the composite resin with enhanced both stiffness and toughness. The flexural and impact strengths reached 159 MPa and 55.4 kJ m−2, which were increased by 36.5% and 129.6%, respectively, compared with the pristine epoxy, meanwhile excellent flame retardance was well maintained (UL-94 V-0 rating). Remarkably, these conjugated phosphaphenanthrene-containing composite resins demonstrate excellent UV-shielding capacity and optical transmittance. In this work, in-situ construction of a crosslinked network with tunable size of phase separation domains can be simply achieved by modulating the ratio of binary curing agents, to fabricate epoxy resins with all-around enhanced performance.生物基阻燃剂因其可持续性和可媲美石油基阻燃剂的效率而受到越来越多的关注，但其与环氧树脂的兼容性问题以及强度和韧性之间的权衡问题却一直困扰着人们。在这里，我们从生物基香兰素和酪胺中开发出了一种希夫碱衍生磷基阻燃剂（TV-DOPO）。在二元固化剂存在的情况下，分层热固化过程和强氢键诱导的纳米级原位构造相分离为复合树脂提供了更高的刚度和韧性。与原始环氧树脂相比，其抗弯强度和冲击强度分别达到了 159 MPa 和 55.4 kJ m-2，分别提高了 36.5% 和 129.6%，同时还保持了优异的阻燃性（UL-94 V-0 级）。值得注意的是，这些含共轭磷菲的复合树脂具有优异的紫外线屏蔽能力和透光率。在这项工作中，只需调节二元固化剂的比例，就能在原位构建具有可调相分离域大小的交联网络，从而制造出性能全面提高的环氧树脂。Super-tough polylactic acid blends via tunable dynamic vulcanization of biobased polyurethanesTao Shou, Qingsheng Dong, Dexian Yin, Shikai Hu, Xiuying Zhao, Liqun Zhangdoi:10.1016/j.compositesb.2024.111363 通过生物基聚氨酯的可调动态硫化实现超强韧性聚乳酸混合物Polylactic acid (PLA) is a biobased plastic with biodegradability, biocompatibility, and high-strength properties; however, its inherent brittleness limits its widespread application. Toughness can be improved by physical blending, chemical copolymerization, and reactive blending of PLA with flexible components. As highly engineered block polymers, polyurethanes (PUs) can improve the toughness of PLA through physical blending or in situ polymerization. However, current research on PU-toughened PLA is hindered by poor compatibility, toughening, and dependence on petrochemical resources. Therefore, to address these issues, we developed a novel biobased millable polyurethane (PO3G-MPU) containing unsaturated double bonds and used it to toughen PLA via peroxide-initiated dynamic vulcanization. The results showed that balancing toughness and strength is possible, with the notched impact strength and tensile strength of the prepared PLA/MPU blends reaching 59.01 kJ/m2 and 43.97 MPa, respectively. The massive shear yielding and plastic deformation of the PLA matrix induced by the crosslinked PO3G-MPU were responsible for the main toughening mechanism. These results provide a new perspective on research on PU-toughened PLA.聚乳酸（PLA）是一种生物基塑料，具有生物降解性、生物相容性和高强度特性，但其固有的脆性限制了它的广泛应用。通过物理混合、化学共聚以及聚乳酸与柔性成分的反应混合，可以改善韧性。聚氨酯（PU）是一种高度工程化的嵌段聚合物，可通过物理共混或原位聚合提高聚乳酸的韧性。然而，目前对聚氨酯增韧聚乳酸的研究受到了相容性差、增韧效果不佳和依赖石化资源等问题的阻碍。因此，为了解决这些问题，我们开发了一种含有不饱和双键的新型生物基可磨聚氨酯（PO3G-MPU），并通过过氧化物引发的动态硫化将其用于增韧聚乳酸。结果表明，可以实现韧性和强度的平衡，制备的聚乳酸/MPU 混合物的缺口冲击强度和拉伸强度分别达到 59.01 kJ/m2 和 43.97 MPa。交联 PO3G-MPU 引起的聚乳酸基体大规模剪切屈服和塑性变形是主要的增韧机制。这些结果为聚氨酯增韧聚乳酸的研究提供了新的视角。Composites Science and TechnologyNumerical analysis of fracture in core-shell particle reinforced compositesWei Fan, Hua Yang, Sheng Mao, Zhenyang Xin, Ambrose C. Taylordoi:10.1016/j.compscitech.2024.110536 芯壳颗粒增强复合材料断裂的数值分析The fracture of core-shell particle reinforced composites was simulated using a crack phase field method. A pre-existing crack may grow along the interface between the core and shell (core debonding), may penetrate the shell and the core (trans-core fracture), or may grow in the matrix (brittle fracture in the matrix). Shell fracture behaviours resulting from the competition between the fracture resistance and fracture driving force are crucial to the crack growth mechanisms. It was found that moderate strength and low modulus of the shell favoured trans-core fracture, and low strength and high modulus of the shell favoured core debonding. The effects on the overall mechanical properties were also identified. The composite strength usually benefited from stiffer and tougher components, regardless of the crack growth mechanisms, while the composite toughness was more complex. The toughening effect was highly related to how the crack evolved, as core debonding improved the toughness at the significant cost of strength, and trans-core fracture contributed most to the toughness with a slight reduction in strength compared with the matrix. These findings indicate design strategies for epoxy composites which can achieve a balance of strength and toughness, enabling the design of safer lightweight composites for electric vehicles and transport applications.采用裂纹相场法模拟了芯壳颗粒增强复合材料的断裂。预先存在的裂纹可能沿着芯壳之间的界面生长（芯壳脱粘），可能穿透芯壳（跨芯断裂），也可能在基体中生长（基体中的脆性断裂）。断裂阻力和断裂驱动力之间的竞争所导致的壳体断裂行为对裂纹生长机制至关重要。研究发现，壳体的中等强度和低模量有利于跨芯断裂，而壳体的低强度和高模量则有利于芯脱开。此外，还确定了对整体机械性能的影响。无论裂纹生长机制如何，复合材料的强度通常得益于较硬和较韧的成分，而复合材料的韧性则更为复杂。增韧效果与裂纹的演变方式密切相关，芯脱落提高了韧性，但强度却大大降低；与基体相比，跨芯断裂对韧性的影响最大，但强度却略有降低。这些发现表明环氧树脂复合材料的设计策略可以实现强度和韧性的平衡，从而为电动汽车和运输应用设计出更安全的轻质复合材料。Synthesising realistic 2D microstructures of unidirectional fibre-reinforced composites with a generative adversarial networkRui Guo, Marco Alves, Mahoor Mehdikhani, Christian Breite, Yentl Swolfsdoi:10.1016/j.compscitech.2024.110539 利用生成式对抗网络合成逼真的单向纤维增强复合材料二维微结构The microstructure governs the behaviour of unidirectional fibre-reinforced composites. In this study, we developed a Deep Convolutional Generative Adversarial Network (DCGAN) to generate realistic 2D transverse microstructures of such composites. We evaluated the DCGAN-generated microstructures using three different methods: Fréchet inception distance, walking through the latent space, and feature matching. The results from these evaluations confirmed that the generated microstructures are distinct and not simply a replication of the training data. The generated microstructures were then compared to real microstructures, confirming that they match qualitatively and quantitatively with respect to detailed statistical characteristics, including fibre diameters, fibre volume fraction, fibre spatial distribution, and resin-rich pockets. We also found that microstructures created by conventional generators could not capture the real resin-rich pockets. This illustrates the capability and value of DCGAN to generate realistic transverse microstructures and provides insights for modelling methods based on real images.微观结构决定着单向纤维增强复合材料的性能。在本研究中，我们开发了一种深度卷积生成对抗网络（DCGAN），用于生成此类复合材料逼真的二维横向微结构。我们使用三种不同的方法对 DCGAN 生成的微结构进行了评估：弗雷谢特起始距离法、潜空间步行法和特征匹配法。这些评估结果证实，生成的微观结构是独特的，而不是训练数据的简单复 制。然后，我们将生成的微结构与真实的微结构进行了比较，确认它们在质量和数量上与详细的统计特征相匹配，包括纤维直径、纤维体积分数、纤维空间分布和富含树脂的口袋。我们还发现，传统发生器生成的微结构无法捕捉到真实的富树脂袋。这说明了 DCGAN 生成真实横向微结构的能力和价值，并为基于真实图像的建模方法提供了启示。来源：复合材料力学仿真Composites FEM
