【新文速递】2023年10月11日复合材料SCI期刊最新文章

今日更新：Composite Structures 1 篇，Composites Part B: Engineering 1 篇，Composites Science and Technology 1 篇

Composite Structures

Three-point bending response and energy absorption of novel sandwich beams with combined re-entrant double-arrow auxetic honeycomb cores

Wang Huiling, Shao Junhua, Zhang Wei, Yan Zhi, Huang Zhengyi, Liang Xuan

doi:10.1016/j.compstruct.2023.117606

新型夹层梁的三点弯曲响应和能量吸收与组合重入式双箭头辅助蜂窝芯

The response and energy absorption of novel sandwich beams with combined re-entrant double-arrow auxetic honeycomb (RDAH) cores subjected to three-point bending were studied experimentally and numerically. Two typical sandwich beams loaded at different loading positions were considered. Quasi-static three-point bending experiments were conducted to obtain the failure modes and force-displacement curves. The reliable numerical simulation models were further established based on experimental validations. The results indicate that when the loading roller is located directly above the re-entrant cell, the RDAH core sandwich beam has better load-carrying and energy absorption capacity. Subsequently, the influence of face sheet distribution, cell-wall thickness, impact velocity and cell configuration on the structural response were explored. For the sandwich beams with same total mass, the arrangement where the thickness of the front face sheet is larger than that of the back face sheet is beneficial for improving the load-carrying and energy absorption capacity. In addition, the cell-wall thickness has an influence on the local deformation mode of the sandwich beam, and increasing its value can produce more stable deformation and improve the load-carrying capacity. Increasing impact velocity has a significant influence on the initial deformation but little influence on the final deformation of the sandwich beams. As the impact velocity increases, the total energy absorption of the sandwich beam gradually increases, and the negative Poisson's ratio characteristic of the core still exists. Compared to the traditional re-entrant honeycomb (RH) core sandwich beams, RDAH core sandwich beams have better energy absorption capacity and bending resistance.

通过实验和数值计算，研究了带有组合再入式双箭头辅助蜂窝（RDAH）芯材的新型夹层梁在受到三点弯曲时的响应和能量吸收情况。研究考虑了两种在不同加载位置加载的典型夹层梁。通过准静态三点弯曲实验获得了破坏模式和力-位移曲线。在实验验证的基础上，进一步建立了可靠的数值模拟模型。结果表明，当加载辊位于再入式单元正上方时，RDAH 核心夹层梁具有更好的承载能力和能量吸收能力。随后，研究人员探讨了面片分布、单元壁厚度、冲击速度和单元配置对结构响应的影响。对于总质量相同的夹芯横梁，前面层厚度大于后面层厚度的布置有利于提高承载能力和能量吸收能力。此外，单元壁厚度对夹层梁的局部变形模式也有影响，增加其值可产生更稳定的变形并提高承载能力。提高冲击速度对夹层梁的初始变形影响很大，但对最终变形影响很小。随着冲击速度的增加，夹层梁的总能量吸收逐渐增加，而夹芯的负泊松比特性仍然存在。与传统的重入式蜂窝芯夹芯梁相比，RDAH 芯夹芯梁具有更好的能量吸收能力和抗弯强度。

Composites Part B: Engineering

Synchrotron micro-CT in kink-band formation of UD-CFRP laminates with microdefects

Srisuriyachot Jiraphant, Bénézech Jean, Couégnat Guillaume, McNair Sophie A.M., Maierhofer Thomas, Butler Richard, Lunt Alexander J.G.

doi:10.1016/j.compositesb.2023.111038

 

具有微缺陷的 UD-CFRP 层压板扭结带形成过程中的同步辐射微计算机断层扫描（Synchrotron micro-CT

This paper presents the first synchrotron micro-Computed Tomography (micro-CT) study on in-situ pure compressive kink-band failure in Uni-Directional Carbon Fibre-Reinforced Polymer composites (UD-CFRPs) with a notch. The study compares the failure behaviour of baseline samples under standard conditions with defect-rich samples containing micro-defects such as voids and fibre misalignment. Quantitative image-based analysis using the structure tensor technique and Digital Volume Correlation (DVC) reveals changes in fibre orientation and localised strain, respectively, at each increment load. A large 400 μ m kink-band inclined at 30° with a half-cosine wave fibre orientation is observed in the baseline samples, while the defect-rich samples form narrower conjugate kink bands (ranging from 77 μ m 25 μ m) inclined at 45°. Development of kink-band formations/failure of both samples is discussed and compared with literature, providing key implications for the design and safe use of this type of composite layup.

本文首次对带有缺口的单向碳纤维增强聚合物复合材料（UD-CFRP）的原位纯压缩扭结带破坏进行了同步辐射微计算机断层扫描（micro-CT）研究。该研究比较了标准条件下基线样品与含有空隙和纤维错位等微缺陷的富缺陷样品的破坏行为。使用结构张量技术和数字体积相关性（DVC）进行的基于图像的定量分析分别揭示了纤维取向和局部应变在每个增量载荷下的变化。在基线样品中观察到一个倾斜 30°、半余弦波纤维取向的 400 μ m 大型扭结带，而缺陷丰富的样品则形成倾斜 45°、较窄的共轭扭结带（从 77 μ m 到 25 μ m 不等）。本文讨论了这两种样品扭结带的形成/失效情况，并与文献进行了比较，从而为设计和安全使用这种复合材料层叠提供了重要依据。

Composites Science and Technology

Effects of lithium insertion induced swelling of a structural battery negative electrode

Larsson Carl, Larsson Fredrik, Xu Johanna, Runesson Kenneth, Asp Leif E.

doi:10.1016/j.compscitech.2023.110299

 

锂插入对结构电池负极膨胀的影响

Structural battery composites fall under the category multifunctional materials with the ability to simultaneously store electrical energy and carry mechanical load. While functioning as the negative electrode, the carbon fibres also act as mechanical reinforcement. Lithium ion insertion in the carbon fibres is accompanied by a large radial expansion of 6.6% and an axial expansion of 0.85 % of the fibres. Furthermore, the elastic moduli of the carbon fibres are significantly affected by the insertion of lithium. Current structural battery modelling approaches do not consider these features. In this paper, we investigate the effect of lithium insertion in carbon fibres on the structural electrode mechanical properties by developing a computational model considering finite strains and lithium concentration dependent fibre moduli. The computational model enables representation of morphological change, whereby, features such as internal stress state, homogenized tangent stiffness and effective expansion of the electrode caused by carbon fibre lithiation can be predicted. The adopted finite strain formulation allows for consistent consideration of measurement data at varying state of lithiation. The significance of adopting the finite strain formulation is also shown numerically. Finally, by implementing a novel approach to homogenized stress-free expansion, it is shown that the computed expansion of the structural electrode follows a similar trend to what is observed from experiments.

结构电池复合材料属于多功能材料，能够同时储存电能和承受机械负荷。碳纤维在充当负极的同时，还起到机械加固的作用。锂离子插入碳纤维后，纤维的径向膨胀率为 6.6%，轴向膨胀率为 0.85%。此外，碳纤维的弹性模量也受到锂插入的显著影响。目前的电池结构建模方法并未考虑这些特征。在本文中，我们通过建立一个考虑有限应变和与锂浓度相关的纤维模量的计算模型，研究了碳纤维中的锂插入对结构性电极机械性能的影响。该计算模型可表示形态变化，从而预测碳纤维锂化引起的内应力状态、均质切线刚度和电极有效膨胀等特征。所采用的有限应变公式允许对不同石化状态下的测量数据进行一致的考虑。采用有限应变公式的重要性也通过数值得到了证明。最后，通过采用新颖的均质化无应力膨胀方法，表明计算得出的结构电极膨胀率与实验观察到的趋势相似。