【新文速递】2024年8月17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 1 篇，Composites Part B: Engineering 2 篇，Composites Science and Technology 2 篇Composite StructuresAn efficient neural network approach for laminated composite plates using refined zigzag theoryVan-Hong Truong, Quang-Huy Le, Jaehun Lee, Jang-Woo Han, Alexander Tessler, Sy-Ngoc Nguyendoi:10.1016/j.compstruct.2024.118476基于精细之字形理论的复合材料层合板神经网络求解方法This paper presents an innovative methodology employing the One-dimensional Convolutional Gated Recurrent Unit neural network (1D-CGRU) algorithm for the analysis of laminated composites using the Refined Zigzag theory (RZT). The RZT methodology is utilized to assess laminated plate structures and generate essential data, forming the basis for training the 1D-CGRU model. The synergistic application of RZT and 1D-CGRU demonstrates exceptional global-local accuracy in predicting the mechanical behavior of laminated composite plates. For efficient data generation, RZT not only provides high precision, but also exhibits computational efficiency, making it suitable for finite element simulations with a C0-continuous kinematic approximation. Additionally, the 1D-CGRU model integrates the strengths of a One-dimensional Convolutional Neural Network (1D-CNN) for spatial feature extraction and dimensionality reduction, coupled with a Gated Recurrent Unit (GRU) network for discerning temporal relationships and mapping them to the target domain. Furthermore, quantitative accuracy measurements, including Mean Squared Error (MSE), Root Mean Squared Error (RMSE), and Mean Absolute Error (MAE), are used to validate the superior performance of the 1D-CGRU model compared to other surrogate models. For angle-ply and cross-ply composite laminates, the 1D-CGRU model achieves remarkable accuracy (98.15% and 99.45%, respectively) with low RMSE values. These results highlight the potential of the proposed framework to enhance predictive analysis for laminated composite structures, offering valuable insights for engineering applications and design optimizations.本文提出了一种采用一维卷积门控递归单元神经网络(1D-CGRU)算法的创新方法，利用精细之字形理论(RZT)对层合复合材料进行分析。RZT方法用于评估层合板结构并生成必要的数据，形成训练1D-CGRU模型的基础。RZT和1D-CGRU的协同应用表明，在预测层合复合材料板的力学行为方面具有卓越的全局-局部精度。为了高效地生成数据，RZT不仅具有高精度，而且具有计算效率，使其适用于具有c0连续运动近似的有限元模拟。此外，1D-CGRU模型集成了一维卷积神经网络(1D-CNN)用于空间特征提取和降维的优势，以及用于识别时间关系并将其映射到目标域的门控循环单元(GRU)网络的优势。此外，定量精度测量，包括均方误差(MSE)、均方根误差(RMSE)和平均绝对误差(MAE)，用于验证1D-CGRU模型与其他替代模型相比的优越性能。对于夹角层合板和交叉层合板，1D-CGRU模型的精度分别为98.15%和99.45%，且RMSE值较低。这些结果突出了所提出的框架在增强层压复合材料结构预测分析方面的潜力，为工程应用和设计优化提供了有价值的见解。Experimental validation of the buckling behavior of unreinforced and reinforced composite conical-cylindrical shells for launch-vehiclesMichelle Tillotson Rudd, Marc R. Schultz, Nathaniel W. Gardner, Cyrus J.R. Kosztowny, Chiara Bisagnidoi:10.1016/j.compstruct.2024.118493运载火箭未加筋与加筋复合材料锥形圆柱壳屈曲性能试验验证Conical-cylindrical shells are common geometries in launch-vehicle structures as stage adapters and payload adapters, and they are susceptible to buckling due to their large radius-to-thickness ratios. Buckling design guidance is available but it is limited for conical and cylindrical shells. There is no available buckling design guidance for conical-cylindrical shells. This paper presents the validation of two finite element models used to successfully predict the buckling behavior of a composite conical-cylindrical shell with and without reinforcement tested in two separate campaigns. The laminate design for the first test campaign consisted of a quasi-isotropic layup. For the second test campaign, additional composite plies were applied to reinforce the transition region of the original laminate. The work presented demonstrates the ability to predict the buckling behavior of a composite conical-cylindrical shells with two different designs, which may aid in creating buckling design guidance for conical-cylindrical shells. Additionally, this paper shows that there is no appreciable benefit to adding reinforcement to the transition region if the intent is to increase the buckling load, due to the fact reinforcement brings increased buckling imperfection sensitivity to the shell.锥形-圆柱形壳体是运载火箭结构中常见的几何形状，作为阶段适配器和有效载荷适配器，由于其较大的半径/厚度比，它们很容易发生屈曲。屈曲设计指南是可用的，但仅限于锥形和圆柱形壳体。锥形圆柱壳的屈曲设计尚无指导。本文提出了两种有限元模型的验证，用于成功地预测复合材料锥形圆柱壳在两个单独的运动中有和没有加筋的屈曲行为。第一次测试活动的层压板设计包括准各向同性层压板。在第二次测试中，使用额外的复合材料层来加强原始层压板的过渡区域。本文的工作证明了预测两种不同设计的复合锥形-圆柱壳屈曲行为的能力，这可能有助于锥形-圆柱壳屈曲设计的指导。此外，本文还表明，如果目的是增加屈曲载荷，则在过渡区增加钢筋没有明显的好处，因为钢筋会增加壳的屈曲缺陷敏感性。Experimental and performance validation of a full–scale morphing droop nose design based on composite compliant structuresAlessandro De Gaspari, Vittorio Cavalieri, Sergio Riccidoi:10.1016/j.compstruct.2024.118502基于复合柔顺结构的全尺寸变形下垂机头设计试验与性能验证Active camber morphing technology can be used to improve aircraft performance in takeoff and landing flight conditions, while preserving a smooth wing shape. This study begins with the design of a morphing droop nose to be installed on a regional aircraft, and focuses on the manufacturing and testing of a full–scale and fully representative experimental prototype. All work is driven by the morphing shape change, which was optimized to provide the required aerodynamic performance. The adoption of a composite structure that combines a flexible skin with a compliant structure makes this device capable of achieving such a shape change, and sufficiently insensitive to external load variations. These capabilities are successfully demonstrated through experimental testing. A validation phase was conducted based on strain gauge measurements, and a motion capture system was used to identify three–dimensional shape changes due to the morphing. Finally, a validated numerical model is used to assess the aerodynamic performance of the experimental prototype.主动弧度变形技术可用于提高飞机在起降飞行条件下的性能，同时保持机翼的光滑形状。本研究从设计安装在支线飞机上的变形下垂机头开始，并着重于制造和测试一个全尺寸和完全具有代表性的实验原型。所有的工作都是由变形的形状变化驱动的，这是经过优化的，以提供所需的气动性能。采用结合柔性蒙皮和柔性结构的复合结构使该装置能够实现这种形状变化，并且对外部负载变化足够不敏感。通过实验测试成功地证明了这些功能。基于应变计测量结果进行了验证阶段，并使用运动捕捉系统识别变形引起的三维形状变化。最后，利用验证的数值模型对实验样机的气动性能进行了评估。Composites Part A: Applied Science and ManufacturingAn innovative model for electrical conductivity of MXene polymer nanocomposites by interphase and tunneling characteristicsZahra Hadi, Jafar Khademzadeh Yeganeh, Muhammad Tajammal Munir, Yasser Zare, Kyong Yop Rheedoi:10.1016/j.compositesa.2024.108422基于界面和隧道特性的MXene聚合物纳米复合材料电导率创新模型The endeavor to forecast the electrical conductivity in composites constituted of MXene nanosheets and polymers presents a significant challenge due to the absence of a simplistic model. The present investigation introduces a comprehensive model that anticipates the electrical conductivity of specimens filled with MXene. The proposed methodology incorporates a multitude of variables that determine the total conductivity of the specimens. These variables encompass the size parameters of MXene, the percolation onset, the volumetric fraction of MXene, the tunneling distance, the interphase thickness, and the network fraction. The reliability of this methodology is rigorously tested using experimental data derived from several specimens. Moreover, a comprehensive examination of the relationship between the estimated conductivity and the variables is carried out to verify the trustworthiness of the suggested approach. The outcomes derived from the suggested model demonstrate a significant alignment with the results from the experiments. Factors such as slender and larger nanosheets, thicker interphase, smaller tunneling distance, and higher portion of percolated nanosheets in the network can significantly enhance the conductivity of nanocomposite. The maximum electrical conductivity of 14 S/m is attained with the lowest tunneling distance of 1.4 nm and the lowest percolation onset of 0.01. Additionally, with the maximum interphase thickness of 41 nm and the highest MXene conductivity of 3×10^6 S/m, the nanocomposite achieves an optimal conductivity of 2 S/m.由于缺乏简单的模型，预测由 MXene 纳米片和聚合物构成的复合材料的导电性是一项重大挑战。本研究引入了一个综合模型，用于预测填充有 MXene 的试样的导电性。所提出的方法包含了决定试样总电导率的多种变量。这些变量包括 MXene 的尺寸参数、渗流起始点、MXene 的体积分数、隧道距离、相间厚度和网络分数。利用从多个试样中获得的实验数据，对该方法的可靠性进行了严格测试。此外，还对估计电导率与变量之间的关系进行了全面检查，以验证所建议方法的可信度。建议模型得出的结果与实验结果非常吻合。细长且较大的纳米片、较厚的相间层、较小的隧道距离以及网络中较高比例的渗滤纳米片等因素可显著提高纳米复合材料的电导率。在隧道距离最小为 1.4 nm、渗流起始点最小为 0.01 的情况下，最大电导率可达 14 S/m。此外，在最大相间厚度为 41 nm、最高 MXene 导电率为 3×10^6 S/m 的情况下，纳米复合材料的最佳导电率为 2 S/m。Composites Part B: EngineeringThermomechanical and damage characterisation of short glass fibre reinforced polyamide 6 and impact-modified polyamide 6 compositesPeihao Song, Akash R. Trivedi, David J. Chapman, Aaron Graham, Nicholas Hawkins, Bratislav Lukić, Alexander Rack, Clive R. Siviourdoi:10.1016/j.compositesb.2024.111767短玻璃纤维增强聚酰胺6和冲击改性聚酰胺6复合材料的热力学和损伤特性Polyamide 6 and its composites are widely used in engineering applications that are exposed to high strain rate deformation. This paper investigates the thermomechanical properties of two polyamide 6 composites, both reinforced with 30 wt% short glass fibres, and one of which additionally contains an impact modifier, to provide an understanding of the mechanical response over a wide range of strain rates and temperatures. Compression experiments were performed at rates between 2 and 3000 s-1, with high speed optical and infrared cameras to aid interpretation of the rate-dependent failure arising from the formation of adiabatic shear bands. Further high strain rate experiments were performed with ultra-fast X-ray phase-contrast imaging to provide in-situ internal damage evaluation. These data will improve the utilization of these composites and aid in development of advanced thermomechanical models.聚酰胺6及其复合材料广泛用于暴露于高应变率变形的工程应用中。本文研究了两种聚酰胺6复合材料的热机械性能，这两种复合材料都是用30wt %的短玻璃纤维增强的，其中一种还含有冲击改性剂，以提供在大范围应变速率和温度下的机械响应的理解。压缩实验在2到3000 s-1之间进行，使用高速光学和红外摄像机，以帮助解释由绝热剪切带形成引起的速率相关破坏。采用超快速x射线相衬成像技术进行高应变速率实验，以提供原位内部损伤评估。这些数据将提高这些复合材料的利用率，并有助于开发先进的热力学模型。Flexible Composite Films with Ultrahigh Through-plane Thermal Conductivity yet Low Graphene ContentJun Jin, Yang Su, Jiachen Guo, Zhongwang Zhang, Bo Peng, Min Chen, Limin Wudoi:10.1016/j.compositesb.2024.111780具有超高通平面热导率和低石墨烯含量的柔性复合薄膜Graphene-based polymeric composites have become one of the promising thermal interface materials (TIMs) for the high integration electronic devices due to the excellent intrinsic thermal conductivity of graphene. However, the challenges still remain, such as ordered alignment of graphene in elastic polymer and regulation of phonon scattering at graphene/graphene interface. In this study, a vertically oriented graphene framework within a flexible silicone rubber matrix was fabricated by non-solvent induced phase separation (NIPs) coupled with an in in-situ welding technique. The as-prepared film exhibits an outstanding through-plane thermal conductivity of 29.5W/mK at low graphene loading of 7.5wt%, which indicates an exceptionally high thermal conductivity enhancement per 1wt% graphene content (specific TCE) over 1950%/wt%. Furthermore, the composite films demonstrate excellent conformability inherited from the silicone rubber matrix and achieves low contact resistance of 40-70 Kmm2W−1 under various pressure and interfacial conditions. This study contributes to a deeper insight into the development of the high-performance graphene-based polymeric TIMs.石墨烯基聚合物复合材料由于其优异的固有导热性能，已成为高集成度电子器件的热界面材料之一。然而，石墨烯在弹性聚合物中的有序排列和石墨烯/石墨烯界面声子散射的调控等挑战仍然存在。在这项研究中，利用非溶剂诱导相分离(NIPs)和原位焊接技术，在柔性硅橡胶基体中制备了垂直定向的石墨烯框架。制备的薄膜在低石墨烯负载为7.5wt%时表现出29.5W/mK的出色通平面导热系数，这表明每1wt%的石墨烯含量(比TCE)在1950%/wt%以上具有异常高的导热系数增强。此外，复合膜继承了硅橡胶基体的优良相容性，在各种压力和界面条件下均可获得40-70 Kmm2W−1的低接触电阻。该研究有助于更深入地了解高性能石墨烯基聚合物TIMs的发展。Composites Science and TechnologyExplosive welding of TA2-SiC-AW5083 composite armorYonggen Cai, Xiaoming Wu, Changgen Shi, Zerui Sun, Xuchuan Luo, Jia Wangdoi:10.1016/j.compscitech.2024.110799 TA2-SiC-AW5083复合装甲的爆炸焊接This study investigates the use of explosive welding to encapsulate SiC between TA2 and 5083, aiming to achieve large-area, high-efficiency, and low-cost fabrication of ceramic composite armor. A new weldability window was established, and six configurations of ceramic composite armor were devised. Ten sets of experiments were conducted to explore the influence of explosive welding parameters, ceramic fracture, and different configurations of composite complate on mechanical properties, macro-deformation, welding interface morphology, and energy absorption and conversion. The research revealed that the fracture of ceramic influences the welding quality, the propagation of the blast wave, and the kinetic energy utilization of the flying plate, while the crevices between the ceramic and the groove on the base plate do not influence the welding quality. When the ceramic remains intact, the kinetic energy utilization rate of the flying plate can be calculated using the η= E1(1-A1/A) /Ef, and when the ceramic penetratively fractures, the kinetic energy utilization rate of the plate can be calculated using the η=(E1-E4) (1-A1/A)/Ef. Finally, we recommend adding a suitable interlayer as a buffer between the flying plate and the ceramic, and the static parameters for explosive welding should strictly adhere to the "Lower bound principle." By analyzing the energy conversion and absorption during the explosive welding process, the macro-deformation and mechanical properties of the composites, the interface morphology, and the level and characteristics of the ceramic fracture, the energy source of the ceramic fracture was found, and the effects of ceramic fracture and structural characteristics of composites on gap airflow, kinetic energy utilization of face plate, explosive wave propagation path, and welding quality were analyzed. Finally, we propose that the explosive welding static parameters of ceramic composite armor should strictly adhere to the " The principle of lower explosives limit."本研究探讨了利用爆炸焊接将碳化硅封装在 TA2 和 5083 之间的方法，旨在实现陶瓷复合装甲的大面积、高效率和低成本制造。研究建立了一个新的可焊性窗口，并设计了六种陶瓷复合装甲构型。通过十组实验，探讨了爆炸焊接参数、陶瓷断裂和不同构型的复合装甲对力学性能、宏观变形、焊接界面形态以及能量吸收和转化的影响。研究发现，陶瓷断裂会影响焊接质量、爆炸波的传播和飞板的动能利用，而陶瓷与底板凹槽之间的缝隙不会影响焊接质量。当陶瓷完好无损时，飞板的动能利用率可通过 η= E1(1-A1/A)/Ef 计算；当陶瓷穿透破裂时，飞板的动能利用率可通过 η=(E1-E4) (1-A1/A)/Ef 计算。最后，我们建议在飞板和陶瓷之间添加合适的中间层作为缓冲，爆炸焊接的静态参数应严格遵守 “下限原则”。通过分析爆炸焊接过程中的能量转换与吸收、复合材料的宏观变形与力学性能、界面形态以及陶瓷断裂的程度与特征，找到了陶瓷断裂的能量来In-situ formation of surface "self-protective" graphitic layer on phenolic resin-based thermal protection compositesShaohang Zheng, Ju Tang, Jin Zhao, Hongqin Liu, Dichu Xu, Ke Li, Dongsheng Wen, Bingjun Zhudoi:10.1016/j.compscitech.2024.110819 酚醛树脂基热防护复合材料表面“自保护”石墨层的原位形成Phenolic resin (PR) composites are widely utilized as thermal protection materials for high-speed aircraft, where their protection mechanisms have been investigated in earlier studies. However, it remained indistinct about the evolution behavior of the outermost surface and its subsequent effects on the ablation performance. Herein, this work re-investigated the morphological transformation and chemical conversion on the outermost surface of a silica fiber-reinforced PR board after ablation by means of combined experimental characterizations at micro- and nanoscale (SEM, TEM, Raman spectroscopy, XRD, XPS) and computational study (ReaxFF-based molecular dynamic simulation). For the first time, our study revealed that its outermost ablated surface demonstrated a distinct evolution behavior in terms of both the in-situ formation of “self-protective” graphitic layer and the radial redistribution of surface carbonaceous substances with different degrees of graphitization, leading to varied ablation resistance along the radial direction of the PR board. In addition, the computational study investigates the ablation-induced graphitization and its influence on the ablative resistance of PR surface. It indicated that, at equivalent energy flux density, PR with graphitized structures exhibited improved thermal protection performance, which can be attributed to decreased thermal conductivity and increased density, leading to a reduced ablation recession rate. Such revelation provides an alternative route in the design of PR-based ablative materials with enhanced ablation resistance.酚醛树脂(PR)复合材料作为高速飞机的热防护材料得到了广泛的应用，其防护机理也得到了较早的研究。然而，对于最外层表面的演化行为及其对烧蚀性能的影响尚不清楚。本文通过微纳米尺度(SEM、TEM、拉曼光谱、XRD、XPS)和计算研究(基于reaxff的分子动力学模拟)相结合的实验表征，重新研究了二氧化硅纤维增强PR板烧蚀后最外层表面的形态转变和化学转化。我们的研究首次揭示了其最外层烧蚀表面在原位形成“自我保护”石墨层和表面不同程度石墨化的碳质物质径向重新分布方面表现出明显的演化行为，导致PR板沿径向方向的烧蚀电阻变化。此外，计算研究了烧蚀诱导石墨化及其对PR表面烧蚀电阻的影响。结果表明，在等效能量通量密度下，石墨化结构的PR具有更好的热防护性能，这可归因于热导率降低和密度增加，从而降低了烧蚀衰退率。这一发现为设计具有增强抗烧蚀性的pr基烧蚀材料提供了另一条途径。来源：复合材料力学仿真Composites FEM