【新文速递】2024年7月17日复合材料SCI期刊最新文章

今日更新：International Journal of Solids and Structures 1 篇，Journal of the Mechanics and Physics of Solids 1 篇，Mechanics of Materials 1 篇，International Journal of Plasticity 1 篇，Thin-Walled Structures 2 篇International Journal of Solids and StructuresFiber-level FE simulation of the braiding process for geometry prediction of braided ropesXu Ding, Junling Liu, Ao Ju, Ying Sun, Li Chendoi:10.1016/j.ijsolstr.2024.112937 对编织过程进行纤维级有限元模拟，以预测编织绳索的几何形状This paper presents a fiber-level finite element model (FE) based on the digital element approach (DEA) for simulating the braiding process and predicting the geometry of tubular braided ropes. The braided yarn is modeled as a bundle of virtual fibers, using chains of truss (rod) elements. In the simulation of the braiding process, a penalty stiffness optimization method is proposed to solve the fiber penetration. The optimization studies show that fiber penetration caused by the combination of insufficient standard penalty stiffness and different number of fibers in the discretized yarn are effectively eliminated until the penetration rate dropped close to 1.85 %. The mesoscopic geometry predictions of models with four kinds of pitch lengths (24 mm, 36 mm, 48 mm, and 60 mm) are validated by quantitative comparison with micro-computed tomography (micro-CT) scans of braided polyarylate fiber ropes. It is shown that geometric convergence of the models can be achieved when each yarn contains 30 fibers. The predicted results of pitch lengths, braiding angles, outer diameters, inner diameters and cross-sectional areas correlate well with those obtained from micro-CT scans.本文介绍了一种基于数字元素方法（DEA）的纤维级有限元模型（FE），用于模拟编织过程和预测管状编织绳的几何形状。使用桁架（杆）元素链将编织纱线建模为一束虚拟纤维。在模拟编织过程中，提出了一种惩罚刚度优化方法来解决纤维穿透问题。优化研究表明，由于标准惩罚刚度不足和离散化纱线中纤维数量不同而导致的纤维穿透现象被有效消除，直到穿透率下降到接近 1.85%。通过与聚芳酯编织纤维绳的微计算机断层扫描（micro-CT）进行定量比较，验证了四种节距长度（24 毫米、36 毫米、48 毫米和 60 毫米）模型的中观几何预测。结果表明，当每根纱线包含 30 根纤维时，模型可实现几何收敛。节距长度、编织角、外径、内径和横截面积的预测结果与显微计算机断层扫描获得的结果相关性良好。Journal of the Mechanics and Physics of SolidsPeridynamic fracture analysis of film–substrate systemsShiyuan Chu, Jinshuai Bai, Zi-long Zhao, Yan Liu, Dan Huang, Bo Li, Qunyang Li, Xi-Qiao Fengdoi:10.1016/j.jmps.2024.105757薄膜-基底系统的周动力断裂分析When subjected to mechanical, thermal, or other loads, film–substrate systems may undergo complex cracking behaviors, which encompasses film and substrate cracking, interfacial debonding, and their combinations, exhibiting rich fracture patterns, such as three-dimensional helical cracks. Identifying the mechanisms underlying these fracture phenomena may lead to more advanced strategies for technologically significant applications. In this paper, we develop an interfacial cohesive peridynamic method for fracture analysis of multiple-phase materials. Particularly, we focus on the modeling of coupled film cracking and interfacial debonding in film–substrate systems. By introducing cohesive interfacial bonds to describe the mechanical properties of the interfaces and adopting a displacement-based cohesive failure criterion, the model is able to predict the critical condition and path of interfacial crack propagation. The robustness of the interfacial cohesive peridynamic method is validated through a series of representative examples. We also demonstrate its efficacy in simulating three-dimensional cracks and identify the essential role of the interfacial energy release rate in controlling the cracking mode transition from a restricted pattern to a helical pattern. The numerical predictions of cracking paths and stress distributions agree well with previous experimental results. This study provides a valuable tool for analyzing different cracking patterns in film–substrate systems and composite materials.当受到机械、热或其他负载时，薄膜-基底系统可能会出现复杂的开裂行为，包括薄膜和基底开裂、界面脱粘以及它们的组合，表现出丰富的断裂模式，如三维螺旋裂纹。找出这些断裂现象的内在机理可能会为具有重大技术意义的应用带来更先进的策略。在本文中，我们开发了一种用于多相材料断裂分析的界面内聚周动力学方法。特别是，我们将重点放在薄膜-基底系统中耦合薄膜开裂和界面脱粘的建模上。通过引入内聚界面键来描述界面的力学特性，并采用基于位移的内聚失效准则，该模型能够预测界面裂纹扩展的临界状态和路径。我们通过一系列具有代表性的实例验证了界面内聚周动力学方法的稳健性。我们还证明了该方法在模拟三维裂纹方面的功效，并确定了界面能量释放率在控制裂纹模式从受限模式向螺旋模式转变过程中的重要作用。对开裂路径和应力分布的数值预测与之前的实验结果非常吻合。这项研究为分析薄膜-基底系统和复合材料中的不同开裂模式提供了有价值的工具。Mechanics of MaterialsConical indentation over a transversely isotropic and layered elastic half-spaceZhijie Jin, Ernian Pan, Zhiqing Zhang, Kaifu Liudoi:10.1016/j.mechmat.2024.105081横向各向同性分层弹性半空间上的锥形压痕We propose a novel method for solving the static response of a conical indenter on a transversely isotropic and layered elastic half-space. The newly developed Fourier-Bessel series (FBS) system of vector functions, along with the unconditionally stable dual-variable and position method, is employed to derive the Green’s function in the transversely isotropic and layered elastic half-space under a vertical ring load on the surface. To calculate the response at different field points on the surface, we apply discrete love numbers within the FBS vector system. The load densities in the discretized rings within the contact radius of the conical indenter are determined using the integral least-squares method, along with a self-adaptive algorithm developed in this study. Finally, the relationship between the indentation depth (vertical displacement) and the applied load is obtained through force balance between the external load and the summed contact traction. The developed scheme is validated using existing exact solutions for the reduced homogeneous half-space case. Selected numerical results clearly demonstrate the effect of anisotropic material and layering on the indentation response. It is observed that, regardless of whether the structure is a stratified half-space or a layered structure with a rigid substrate, the material properties in the top layer have the most significant influence on the indentation behavior. In the case of a layered structure with an underlying elastic half-space, the material properties in the interlayer and bottom layer could also affect the indentation behaviors.我们提出了一种新方法，用于求解锥形压头在横向各向同性分层弹性半空间上的静态响应。我们采用新开发的傅里叶-贝塞尔序列（FBS）矢量函数系统以及无条件稳定的双变量和位置法，推导了在表面垂直环载荷作用下横向各向同性分层弹性半空间中的格林函数。为了计算表面上不同场点的响应，我们在 FBS 向量系统中应用了离散爱数。锥形压头接触半径内离散环的载荷密度采用积分最小二乘法和本研究开发的自适应算法确定。最后，通过外部载荷与总接触牵引力之间的力平衡，得出压痕深度（垂直位移）与施加载荷之间的关系。利用现有的精确解法对所开发的方案进行了验证，该方案适用于缩小的均质半空间情况。选定的数值结果清楚地表明了各向异性材料和分层对压痕响应的影响。据观察，无论结构是分层的半空间还是具有刚性基底的分层结构，顶层的材料特性对压痕行为的影响最大。在底层为弹性半空间的分层结构中，层间和底层的材料特性也会影响压痕行为。International Journal of PlasticitySlip-discreteness-corrected strain gradient crystal plasticity (SDC-SGCP) theoryRan Chen, Guisen Liu, Peidong Wu, Jian Wang, Lei Zhang, Yao Shendoi:10.1016/j.ijplas.2024.104054 滑动不稳定性校正应变梯度晶体塑性（SDC-SGCP）理论Strain gradient plasticity theory addresses the plastic strain gradient induced hardening by considering the internal stress and Taylor hardening associated with the geometrically necessary dislocations (GNDs). However, the continuum description of internal stress associated with GNDs is inaccurate due to the coarsening of discrete dislocations. Corrections are thus derived as the difference between the stresses produced by the continuous configuration and the discrete configuration. We further demonstrate the capability of this correction in effectively capturing the internal stress induced strengthening effect associated with GNDs, and elucidate that its role in strengthening is to homogenize the deformation and extend the influence of grain boundaries into the interior of grains within polycrystals. This capability to capture intragranular slip distribution is validated through the simulation of a polycrystalline tensile experiment. This work explains the limitations of classical crystal plasticity theory under high strain gradients and offers a straightforward yet robust slip discreteness correction to crystal plasticity with transparent input from dislocation theory, opening a new perspective for the connections between continuum crystal plasticity theory and dislocation theory.应变梯度塑性理论通过考虑与几何必要位错（GND）相关的内应力和泰勒硬化来解决塑性应变梯度引起的硬化问题。然而，由于离散位错的粗化，与 GNDs 相关的内应力连续描述并不准确。因此，我们根据连续构型与离散构型所产生的应力之差进行了修正。我们进一步证明了这一校正在有效捕捉与 GND 相关的内应力诱导强化效应方面的能力，并阐明其在强化中的作用是使变形均匀化，并将晶界的影响扩展到多晶体内的晶粒内部。通过模拟多晶体拉伸实验，验证了这种捕捉晶粒内部滑移分布的能力。这项工作解释了经典晶体塑性理论在高应变梯度下的局限性，并提供了一种直接而稳健的晶体塑性滑移离散性校正方法，同时提供了透明的位错理论输入，为连续晶体塑性理论与位错理论之间的联系开辟了新的视角。Thin-Walled StructuresAchieving high strength and energy absorption of novel 3D printed helical layered square honeycombsPing Xia, Nan Li, Hua Fu, Lijuan Wang, Haolin Qin, Chenfu Xiong, Xue Yu, Qingyuan Wang, Cunxian Wang, Feng Zhaodoi:10.1016/j.tws.2024.112155实现新型 3D 打印螺旋分层方形蜂窝的高强度和能量吸收Bionics shape design of cellular structures has the potential advantage of improving their both mechanical properties and energy absorption capabilities to the conventional honeycomb structures. In this article, inspired by square porous wood and DNA double helix, we demonstrate the creation of the novel helical layered square honeycombs (HLSHs) that simultaneously exhibit high strength and excellent energy absorption capacity. In-plane compression experiments and finite element simulations revealed that helical structure can effectively strengthen every unit cell to resist local stress concentration which always leads to rapid strain localization and finally followed by catastrophic collapse. Furthermore, the stiffness, strength and energy absorption capability can be continuously improved by increasing the number of helical layers. More specifically, the HLSH-4L (4 layers) exhibits higher collapse stress (∼176%) and specific absorption energy (∼502%) compared with that of regular square honeycomb (RESH). The investigation of deformation and failure behavior show that the helical structure can supply high cell-buckling resistance and facilitate the “X” shape deformation band. Besides, the helical structure also caused the transition of failure mechanisms from printing fibers tearing in RESH to layer cracking in HLSHs. This study can present insight into the design of lighter and stronger honeycomb.与传统的蜂窝结构相比，细胞结构的仿生形状设计具有改善其机械性能和能量吸收能力的潜在优势。本文受方形多孔木材和 DNA 双螺旋的启发，展示了新型螺旋分层方形蜂窝（HLSHs）的创造，这种蜂窝同时表现出高强度和出色的能量吸收能力。面内压缩实验和有限元模拟显示，螺旋结构能有效强化每个单元格，以抵御局部应力集中，而局部应力集中总会导致应变快速局部化，最终导致灾难性坍塌。此外，通过增加螺旋层数，还能不断提高刚度、强度和能量吸收能力。更具体地说，与普通方形蜂窝（RESH）相比，HLSH-4L（4 层）表现出更高的坍塌应力（∼176%）和比吸收能（∼502%）。对变形和破坏行为的研究表明，螺旋结构能提供较高的单元抗弯曲性，并能促进 "X "形变形带的形成。此外，螺旋结构还使失效机制从 RESH 的印刷纤维撕裂过渡到 HLSH 的层裂。这项研究可为设计更轻、更强的蜂窝提供启示。Mechanical Properties of Hoberman Radially Retractable Roof StructuresYutao Wang, Qian Zhang, Ning Pan, Yixiang Xu, Dong Lu, Jianguo Cai, Jian Fengdoi:10.1016/j.tws.2024.112176霍伯曼径向可伸缩屋顶结构的机械特性In this paper, a spatial Hoberman radially retractable grid shell is constructed based on its planar version and the mechanical properties of the grid shell are analyzed using ABAQUS commercial software. The analysis shows that given carefully chosen parameters, the spatial grid shell can meet the requirements of the specification. Based on this, the influence of the number of multi-angulated rods, the number of segments of the multi-angulated rod, and the rise-span ratio on the mechanical performance of the structure are analyzed. The results show that the increase of the number of multi-angulated rods is beneficial to the mechanical properties of the structure, but will have a negative effect on the economic performance. To reach an optimized configuration, it is chosen such that the number of multi-angulated rods is 18, the steel consumption and the structural performance response are smaller. The decrease of the number of segments of the multi-angulated is beneficial to the mechanical properties, service performance, and economic performance of the structure, but considering the feasibility of processing, transportation and the driving condition setting, it is recommended to choose 4 segments of the multi-angulated rod. Higher rise-span ratio is beneficial to the mechanical properties of the structure in the closed state, but will adversely affect the mechanical properties and economic performance during the deployment.本文在其平面版本的基础上构建了空间霍伯曼径向可伸缩网格壳体，并使用 ABAQUS 商业软件分析了网格壳体的力学性能。分析结果表明，只要精心选择参数，空间网格壳就能满足规范要求。在此基础上，分析了多刚架杆件数量、多刚架杆件段数和升跨比对结构力学性能的影响。结果表明，增加多棱杆的数量有利于结构的力学性能，但会对经济性能产生负面影响。为了达到最佳配置，选择了多棱杆数量为 18，钢材消耗量和结构性能响应较小的配置。减少多棱杆的节数有利于结构的力学性能、使用性能和经济性能，但考虑到加工、运输的可行性和行车条件的设置，建议选择 4 节多棱杆。较高的升跨比有利于结构在闭合状态下的力学性能，但会对展开时的力学性能和经济性产生不利影响。来源：复合材料力学仿真Composites FEM