【新文速递】2023年11月2日复合材料SCI期刊最新文章

今日更新：Composite Structures 5 篇，Composites Part A: Applied Science and Manufacturing 2 篇，Composites Part B: Engineering 2 篇

Composite Structures

Prediction of elastic properties of 3D4D rotary braided composites with voids using multi-scale finite element and surrogate models

Huang Hao, Guo Zitong, Shan Zhongde, Sun Zheng, Liu Jianhua, Wang Dong, Wang Wang, Liu Jiale, Tan Chenchen

doi:10.1016/j.compstruct.2023.117579

利用多尺度有限元和代用模型预测带有空隙的 3D4D 旋转编织复合材料的弹性特性

The conventional evaluation of 3D braided composites' mechanical properties through numerical and experimental methodologies serves as a hindrance to material application owing to the considerable expenses, time constraints, and laborious efforts involved. Moreover, the presence of void defects induced during the processing exacerbates this challenge. In this study, a multi-scale finite element model (FEM) and a surrogate model are established for predicting elastic properties of three dimensional four directional (3D4D) rotary braided composites with voids for the first time. Based on the established FEM, a comprehensive dataset containing 768 data points is formed, covering the ranges of both design parameters and void defect parameters. The influence of braiding angle, yarn width, and porosity, on the elastic constants of 3D4D rotary braided composites is accurately analyzed. A genetic algorithm-optimized back propagation neural network (GABPNN) model is developed, which possess the capability to replicate FEM outcomes with a commendable R-value of 0.99. The remarkable concordance between the anticipated outcomes and experimental datasets corroborates the triumphant implementation of the present method in unraveling the interconnections between microstructure and properties in 3D4D rotary braided composites containing voids. Consequently, this offers a propitious instrument for expediting the intelligent conception and refinement of composite materials.

通过数值和实验方法对三维编织复合材料的机械性能进行传统评估，是材料应用的一大障碍，因为这涉及到大量的费用、时间限制和费力工作。此外，加工过程中产生的空隙缺陷也加剧了这一挑战。本研究首次建立了多尺度有限元模型（FEM）和代用模型，用于预测带有空隙的三维四向（3D4D）旋转编织复合材料的弹性特性。基于建立的有限元模型，形成了包含 768 个数据点的综合数据集，涵盖了设计参数和空隙缺陷参数的范围。精确分析了编织角、纱线宽度和空隙率对 3D4D 旋转编织复合材料弹性常数的影响。建立了遗传算法优化反向传播神经网络（GABPNN）模型，该模型具有复 制有限元结果的能力，R 值高达 0.99。预期结果与实验数据集之间的显着一致性证实了本方法在揭示含有空隙的 3D4D 旋转编织复合材料的微观结构与性能之间的相互联系方面的成功应用。因此，这为加快复合材料的智能构思和改进提供了有利工具。

Additive Manufacturing Error Quantification on Stability of Composite Sandwich Plates with Lattice-Cores through Machine Learning Technique

Tian Weizhe, Li Qingya, Wang Qihan, Chen Da, Gao Wei

doi:10.1016/j.compstruct.2023.117645

通过机器学习技术量化网格孔复合材料三明治板稳定性的增材制造误差

Architected lattice structures are designed to achieve specific mechanical properties while maintaining relative lightweight. Additive Manufacturing (AM) facilitates the fabrication of lattice structures with complex geometries. However, manufacturing imperfections, e.g., node dislocation, radius variation, and waviness, inevitably affect the performance of composite structures, of which the impact is significant yet difficult to quantify. Herein, a virtual model-assisted AM error quantification scheme is proposed to alleviate this challenge. The influence of geometric imperfections on the static buckling behaviour for sandwich lattice-core panels is investigated. A recently developed Extended Support Vector Regression (X-SVR) is utilized to alternatively bridge multiscale analyses. By integrating the sampling and virtual modelling methods, the effect of AM errors can be comprehensively quantified with statistical moments, probability density function (PDF), cumulative distribution function (CDF), etc. Furthermore, high computational efficiency, robustness, and other inherent features highlight the applicability of the proposed AM error quantification scheme in engineering.

建筑晶格结构旨在实现特定的机械性能，同时保持相对轻质。快速成型技术（AM）有助于制造具有复杂几何形状的晶格结构。然而，制造缺陷（如节点错位、半径变化和波浪度）不可避免地会影响复合结构的性能，其影响巨大却难以量化。本文提出了一种虚拟模型辅助 AM 误差量化方案，以缓解这一难题。研究了几何缺陷对夹层格状芯板静态屈曲行为的影响。利用最近开发的扩展支持向量回归（X-SVR）来替代多尺度分析。通过集成采样和虚拟建模方法，可以利用统计矩、概率密度函数（PDF）、累积分布函数（CDF）等全面量化 AM 误差的影响。此外，计算效率高、鲁棒性强等固有特点也凸显了所提出的 AM 误差量化方案在工程中的适用性。

A novel analytical model for Fiber Reinforced Cementitious Matrix FRCM coupons subjected to tensile tests

Pingaro Natalia, Milani Gabriele

doi:10.1016/j.compstruct.2023.117666

纤维增强水泥基质 FRCM 拉伸试验试样的新型分析模型

A much enhanced -with respect to existing literature- analytical model for FRCM coupons subjected to standard tensile tests is proposed. One fourth of the coupon is idealized considering two layers, matrix and fiber, subjected to a uniaxial stress state, mutually interacting at the interface through tangential stresses. The matrix is assumed elastic-perfectly fragile and the fiber linear elastic. The shear stress-slip relationship at the interface is tri-linear, with the first phase elastic, the second exhibiting linear softening followed by a third phase at possible non-null residual strength. The longitudinal equilibrium equations written for the two layers, suitably re-arranged, allow to deduce a field problem governed in the three phases by a single second order linear differential equation where the independent variable is the interface slip, with solution retrievable analytically. Since the location of the points where the interface is in the different phases is not a-priori known, a discretization with small length elements is adopted. For each element the solution of the field problem is known in closed form and the only variables to determine are the integration constants coming from the solution of the differential equation. After a standard assemblage, all constants are derived imposing the boundary conditions at the extremes of the elements, which depend on the state of cracking of the matrix layer. The model is validated against two sets of experimental data on coupons tested in two different University laboratories in Italy. A satisfactory predictivity of both the global and local behavior is found.

与现有文献相比，本研究提出了一种更先进的分析模型，用于对 FRCM 试样进行标准拉伸试验。将试样的四分之一理想化，考虑两层基体和纤维，承受单轴应力状态，通过切向应力在界面上相互作用。基体假定为完全脆性弹性体，纤维假定为线性弹性体。界面处的剪应力-滑移关系为三线性关系，第一阶段为弹性，第二阶段为线性软化，第三阶段可能为非零残余强度。通过对两层的纵向平衡方程进行适当的重新排列，可以推导出一个由单个二阶线性微分方程（其中自变量为界面滑移）控制的三相场问题，该方程的解可以通过分析获得。由于界面在不同阶段的点的位置并不是事先已知的，因此采用了小长度元素离散化方法。对于每个元素，场问题的解都是已知的闭合形式，唯一需要确定的变量是来自微分方程解的积分常数。在进行标准组合后，所有常数都是根据基质层的开裂状态，在元素的极值处施加边界条件推导出来的。该模型通过两组在意大利两所不同大学实验室测试的试样实验数据进行了验证。结果表明，该模型对整体和局部行为的预测能力都令人满意。

Thermal stress analysis of variable angle tow composite plates through high-order structural models

Pagani A., Zappino E., Bracaglia F., Masia R., Carrera E.

doi:10.1016/j.compstruct.2023.117668

通过高阶结构模型对变角牵引复合板进行热应力分析

This work focuses on thermo-elastic analysis of Variable Angle Tow (VAT) composite plates. Emphasis is given to the through-the-thickness 3D stress component distributions as a consequence of constant temperature profiles. High-order structural models are used, in order to take into account the volumetric and the distortion contributions. The last contribute arise from boundary conditions or asymmetric staking sequences. Governing equations of the uncoupled thermo-elastic problem are derived in the domain of the Carrera Unified Formulation (CUF), which in turn is coupled with a classical finite element method to obtain opportune numerical solutions. The advantage of using CUF lies in the fact that different theories of structures can be implemented automatically and a critical study on the use of standard to high-order plate finite elements can be performed with ease. In this manner we classify models based on their efficiency and depending on the degree of accuracy needed, both in terms of displacements and stresses. Different numerical problems are considered and it is demonstrated that layerwise approximations are needed whenever shear stresses trends are of interest. Boundary Conditions influence more the choice of the adequate expansion theory otherwise.

这项工作的重点是对可变角弓（VAT）复合板进行热弹性分析。重点是恒温剖面导致的通厚三维应力分量分布。采用高阶结构模型，以考虑体积和变形的贡献。最后的贡献来自于边界条件或不对称定点序列。非耦合热弹性问题的支配方程是在卡雷拉统一公式（CUF）域中导出的，而卡雷拉统一公式又与经典的有限元方法相结合，以获得合适的数值解。使用 CUF 的优势在于可以自动实现不同的结构理论，并且可以轻松地对从标准到高阶板有限元的使用进行批判性研究。通过这种方式，我们根据模型的效率以及在位移和应力方面所需的精确度对模型进行分类。我们考虑了不同的数值问题，结果表明，只要对剪应力趋势感兴趣，就需要分层近似。否则，边界条件对选择适当的扩展理论影响更大。

Topological acoustic waveguide with high-precision internal-mode-induced multiband

Ma Chengzhi, Hui Wu Jiu, Cui Zhanyou, Wang Linbo

doi:10.1016/j.compstruct.2023.117681

具有高精度内模诱导多频带的拓扑声波导体

In this paper, we propose a topological acoustic waveguide which can transmit high-precision and multiband sound energy with backscattering suppression and no energy loss. It is a kind of acoustic waveguide with spatial lattice uniformity without destroying lattice position. This acoustic structure is obtained by integrating two kinds of multi-stage resonators arranged in a triangular lattice pattern in the air environment. On one hand, the introduction of internal modes greatly improves the transmission accuracy of topological acoustic waveguide compared with the Bragg scattering alone under the same overall structure size. On the other hand, it greatly improves the utilization rate of the internal space of the structure and makes full use of the multi-modal in structure to construct more sound transmission bands. After introducing the rotational scattering mechanism, the numerical and experimental results show that up to seven high-precision acoustic transmission channels with backscattering suppression and no energy loss below 14 kHz are obtained along the sonic crystal interface with different topological states in this topological acoustic waveguide. This research paves the way for engineering applications of high-precision acoustic transmission, multi-band acoustic antennas, acoustic logic control, covert sound transmission and other multifunctional acoustic devices.

本文提出了一种拓扑声波导体，它可以传输高精度、多频段的声能，并具有抑制反向散射和无能量损失的特点。它是一种具有空间晶格均匀性且不破坏晶格位置的声波导。这种声学结构是通过在空气环境中集成两种以三角晶格模式排列的多级谐振器而获得的。在整体结构尺寸相同的情况下，内部模式的引入与单纯的布拉格散射相比，一方面大大提高了拓扑声学波导的传输精度。另一方面，它大大提高了结构内部空间的利用率，充分利用结构中的多模态构造出更多的声音传输频带。在引入旋转散射机制后，数值和实验结果表明，在这种拓扑声波导管中，沿着不同拓扑状态的声晶界面，可以获得多达七个抑制反向散射且在 14 kHz 以下无能量损失的高精度声波传输通道。这项研究为高精度声波传输、多波段声波天线、声波逻辑控制、隐蔽声波传输和其他多功能声波器件的工程应用铺平了道路。

Composites Part A: Applied Science and Manufacturing

Transverse compaction of twisted carbon yarns: Experiment and elasto-plastic Mohr–Coulomb modeling

Rubino Marcello, Wielhorski Yanneck, Roux Stéphane

doi:10.1016/j.compositesa.2023.107873

 

加捻碳纱的横向压实：实验和弹塑性莫尔-库仑模型

The mechanical characterization of the carbon yarns, the major component of woven textiles for composite materials, is essential for optimizing the fabrication and the final properties of such materials. This work focuses on carbon yarns formed by twisting several elementary tows, each composed of thousands of carbon fibers, whose weak cohesion is ensured by a sizing agent. Different twist magnitudes are studied in dry and wet conditions. Transverse compaction tests are performed with loading-unloading cycles of increasing amplitudes. They have shown that the yarn cross section approaches a critical state where the fiber volume fraction remains constant, irrespective of twist level and humidity. The experimental results evidence an elasto-plastic behavior, analogous to that of a 2D granular medium. A simple model is proposed with a cohesive non-associated Mohr–Coulomb plasticity, having very few constitutive parameters. The effect of twist, water, and sizing can be accounted for.

碳纱是复合材料编织纺织品的主要成分，对碳纱进行机械表征对于优化此类材料的制造和最终性能至关重要。这项研究的重点是碳纱，碳纱是由几条基本纤维束加捻而成，每条纤维束都由数千根碳纤维组成，上浆剂确保了纤维束的弱内聚力。研究了在干燥和潮湿条件下的不同捻度。横向压实试验是在加载-卸载循环中进行的，加载-卸载循环的振幅不断增大。结果表明，纱线横截面接近临界状态，在这种状态下，纤维体积分数保持不变，与捻度和湿度无关。实验结果表明，纱线具有类似于二维颗粒介质的弹塑性行为。我们提出了一个简单的模型，它具有内聚的非相关莫尔-库仑塑性，只需很少的构成参数。扭转、水和施胶的影响均可考虑在内。

Characterization of tool-ply friction behavior for treated jute/PLA biocomposite prepregs in thermoforming

zhang Wenwu, Zhou Helezi, Huang Bin, Zhou Huamin, Peng Xiongqi

doi:10.1016/j.compositesa.2023.107875

热成型过程中经处理的黄麻/PLA 生物复合预浸料的工具层摩擦行为表征

This paper investigates the tool-ply friction behavior of woven jute fabric reinforced poly-lactic acid (jute/PLA) biocomposite in thermoforming. A home-made pull-through friction testing device was developed to characterize the tool-ply friction behavior of the jute/PLA prepreg at elevated temperature. The effects of alkali treatment, fiber orientation, normal force and slipping velocity were studied. The results suggested a strong relationship between the tool-ply friction behavior and the woven and fiber structures. In addition, a quantitative definition of the tool-ply friction behavior was achieved by introducing the characteristic stress and friction coefficient. These findings indicated a hydrodynamic lubrication of tool-ply friction. This work provides a beneficial complement to the understanding of the thermoforming process of jute/PLA biocomposites.

本文研究了热成型中黄麻织物增强聚乳酸（黄麻/PLA）生物复合材料的工具层摩擦行为。为了表征黄麻/聚乳酸预浸料在高温下的工具层摩擦行为，我们开发了一种自制的拉穿摩擦测试装置。研究了碱处理、纤维取向、法向力和滑动速度的影响。结果表明，工具层摩擦行为与编织结构和纤维结构之间存在密切关系。此外，通过引入特征应力和摩擦系数，实现了工具层摩擦行为的定量定义。这些研究结果表明了工具层摩擦的流体动力润滑。这项研究为了解黄麻/PLA 生物复合材料的热成型过程提供了有益的补充。

Composites Part B: Engineering

Interfacial debonding mechanism of magnesium phosphate cement onto old concrete substrates under freeze-thaw conditions

Zhou Zihan, Wang Qiang, Shen Yanjun, Zhou Yu

doi:10.1016/j.compositesb.2023.111076

冻融条件下磷酸镁水泥与旧混凝土基面的界面剥离机制

The interface created by the repair of damaged ordinary Portland concrete (OPC) structures using magnesium phosphate cement (MPC) is prone to cracking and debonding under freeze-thaw (F-T) conditions and may even cause engineering disasters. In this study, the entire debonding process, moisture migration and debonding mechanism of the MPC-OPC composite interface under F-T actions were investigated and a novel mixed mode fracture criterion was established. The primary findings are drawn as follows: (i) The interfacial crack initiates and propagates along the interface or kinks into the MPC side during F-T actions, depending on the position and thickness of the localized interface F-T damage zone (IFDZ) close to the interface on the MPC side; (ii) The net suction force causes capillary and film water in the mesopores and micropores to migrate to the freezing macropores inside the interface layer, whereas the increase in the liquid pressure caused by the water-ice phase transition causes crack initiation in the macropores and even the interface layer damage; (iii) The stiffness difference between MPC and OPC increases as the molar ratio of magnesia and phosphate (M/P) or the mass ratio of water to cement (W/B) of MPC increases, and the interface debonding mode shifts from propagating along the interface to kinking into the MPC side.

使用磷酸镁水泥（MPC）修复受损的普通硅酸盐混凝土（OPC）结构所形成的界面在冻融（F-T）条件下容易开裂和脱粘，甚至可能造成工程灾难。本研究对 F-T 作用下 MPC-OPC 复合界面的整个脱粘过程、水分迁移和脱粘机理进行了研究，并建立了新的混合模式断裂准则。主要研究结果如下(i) 在 F-T 作用下，界面裂纹沿着界面开始扩展或向 MPC 侧弯曲，这取决于 MPC 侧靠近界面的局部界面 F-T 损伤区（IFDZ）的位置和厚度；(净吸力导致中孔和微孔中的毛细管水和薄膜水迁移到界面层内部的冻结大孔中，而水冰相变引起的液压力增加则导致大孔中的裂纹萌生，甚至造成界面层破坏；(iii) MPC 和 OPC 之间的刚度差随着 MPC 的菱镁和磷酸盐摩尔比 (M/P) 或水与水泥的质量比 (W/B) 的增加而增大，界面脱粘模式从沿界面传播转变为向 MPC 侧扭结。

Effect of carbonation on the corrosion behavior of steel rebar embedded in magnesium phosphate cement

Wang Danqian, Yue Yanfei, Qian Jueshi

doi:10.1016/j.compositesb.2023.111088

碳化对嵌入磷酸镁水泥中的钢筋腐蚀行为的影响

Magnesium Potassium Phosphate Cement (MKPC) as a protective binder for steel has been well-established. However, corrosion performance of steel rebars in MKPC subjected to carbonation is still unknown. This investigation is aimed to reveal impact and mechanism of carbonation on corrosion performance of steel rebar in MKPC using electrochemical techniques and surface analysis. The findings indicate that, unlike Portland cement (PC) system, carbonation positively influences corrosion performance of steel rebar when embedded in MKPC, as demonstrated by comparable (M/P = 7) or even higher (M/P = 12) corrosion resistance values. Under carbonation, the ingressive CO2 reacts with Mg-bearing phases in MKPC to form nesquehonite with a higher pH, while the MgO still keep supersaturated. The resultant increase in pH facilitates formation of ferrous oxide and iron phosphate/borate within oxide film developed on steel surface, which enhances protective capability of oxide film and consequently improves the corrosion resistance of the steel rebar.

镁钾磷酸盐水泥（MKPC）作为钢材保护粘结剂已得到广泛认可。然而，MKPC 中的钢筋在碳化作用下的腐蚀性能仍是未知数。本研究旨在利用电化学技术和表面分析揭示碳化对 MKPC 中钢筋腐蚀性能的影响和机理。研究结果表明，与硅酸盐水泥（PC）体系不同，碳化对埋入 MKPC 的钢筋的腐蚀性能有积极影响，表现在耐腐蚀性值相当（M/P = 7）甚至更高（M/P = 12）。在碳化过程中，侵入的二氧化碳与 MKPC 中的含镁相发生反应，形成 pH 值更高的黑沸石，而氧化镁仍保持过饱和状态。因此，pH 值的升高有利于在钢表面形成的氧化膜中形成氧化亚铁和磷酸铁/硼酸盐，从而增强氧化膜的保护能力，进而提高钢筋的耐腐蚀性。