今日更新：International Journal of Solids and Structures 2 篇，Journal of the Mechanics and Physics of Solids 2 篇，International Journal of Plasticity 1 篇，Thin-Walled Structures 1 篇International Journal of Solids and StructuresDeformation-activated polarization-selective negative group velocity in rectangularly-arranged fiber-reinforced soft compositeQi Yao, Stephan Rudykhdoi:10.1016/j.ijsolstr.2025.113785矩形排列纤维增强软复合材料变形激活极化选择负群速度This paper demonstrates the deformation-activated negative group velocity (NGV) state in soft fiber-reinforced composites (soft FCs). We exhibit the mechanis m of inducing the NGV state in the vicinity of buckling. Based on extensive simulations, we construct a map of NGV intervals versus deformation level and fiber spacing ratio, revealing clear trends and tunable behavior. In the transition region of buckling direction, NGV states can be selectively activated for shear waves with different polarizations. The presence and order of NGV polarizations are found to correlate with the direction of post-buckling fiber morphology. NGV states in both polarizations indicate non-principal, helical buckling patterns and complex evolutions. The relative width of NGV intervals of two polarizations mirrors the magnitude of helical deformation in each direction. These findings suggest NGV behavior as a predictive indicator for post-buckling configurations. This work offers a new pathway for understanding NGV states in soft FCs, with potential applications in reconfigurable materials.研究了软纤维增强复合材料（soft fc）的变形激活负群速度（NGV）状态。我们展示了在屈曲附近诱导NGV状态的机制。基于大量的模拟，我们构建了NGV层段与变形水平和纤维间距比的关系图，揭示了清晰的趋势和可调行为。在屈曲方向的过渡区，NGV状态可以被不同极化的剪切波选择性激活。发现NGV极化的存在和顺序与屈曲后纤维形态的方向有关。NGV在两种极化状态下均表现出非主的螺旋屈曲模式和复杂的演化。两个极化NGV间隔的相对宽度反映了每个方向上螺旋变形的大小。这些发现表明NGV行为可以作为后屈曲结构的预测指标。这项工作为理解软fc中的NGV状态提供了新的途径，在可重构材料中具有潜在的应用前景。A single-DoF deployable parabolic truss antenna mechanis m based on equilateral triangle profile division and scissor mechanis mXinlu Wei, Enbo Liu, Shichao Sun, Bo Chen, Yundou Xu, Qifeng Cui, Yongsheng Zhaodoi:10.1016/j.ijsolstr.2025.113784一种基于等边三角形剖分和剪刀机构的单自由度可展开抛物桁架天线机构This paper proposes a single-degree-of-freedom (DoF) deployable parabolic truss antenna mechanis m based on equilateral triangle Profile Division, which incorporates scissor mechanis ms to achieve high deployment-to-stow ratio and stable deployment. Addressing the issues of limited configuration types, excessive DoFs, and poor deployment coordination in existing truss mesh antennas, this study introduces an equilateral triangle Profile Division method and a deployable antenna configuration design. Through kinematic an alysis, it is verified that the mechanis m possesses a single-DoF characteristic. Finally, the gravity compensation suspension points of this antenna mechanis m are optimized, and simulation an alysis is conducted. The feasibility and effectiveness of the design are verified through a prototype. This antenna mechanis m, characterized by high structural density, good motion coordination, excellent structural and rotational symmetry, and ease of fabrication, provides a reference for solving the problem of uncontrollable deployment processes leading to deployment failures in existing antennas.提出了一种基于等边三角形剖分的单自由度可展开抛物桁架天线机构，该机构结合剪刀机构实现了高展载比和稳定展开。针对现有桁架网状天线构型类型有限、自由度过大、部署协调性差等问题，提出了一种等边三角形剖分方法和一种可展开天线构型设计。通过运动学分析，验证了该机构具有单自由度特性。最后，对该天线机构的重力补偿悬挂点进行了优化，并进行了仿真分析。通过样机验证了设计的可行性和有效性。该天线机构具有结构密度高、运动协调性好、结构和旋转对称性好、易于制作等特点，为解决现有天线部署过程不可控导致部署失败的问题提供了参考。Journal of the Mechanics and Physics of SolidsAnomalous quasiplasticity, spallation, and thermal damage in fused silica under laser-induced quadruple stress waves and multi-field coupling effectsDinghuai Yang, Zhichao Liu, Jian Cheng, Mingjun Chen, Linjie Zhao, Shengfei Wang, Feng Geng, Yazhou Sun, Qiao Xudoi:10.1016/j.jmps.2025.106445 熔融石英在激光诱导的四重应力波和多场耦合效应下的异常准塑性、剥落和热损伤Spallation and thermal damage limit the application of fused silica under extremely intense lasers. Herein, the unclear underlying mechanis ms, including extreme-irradiation-induced plasticity-related behaviors were studied based on first-constructed cross-scale models, molecular dynamics simulation, and multimodal characterization. Material spallation originated from the anomalous “quasiplasticity” and phased propagation of micro-cracks under quadruplex elastoplastic waves. Although the fastest primary wave could not cause macroscopic deformation, it could lead to micro-plasticity phenomena (ring-structure transformation and point-defect proliferation) due to material phase transformation and destabilizing effects. Subsequently, conjugate secondary and head elastoplastic waves governed initialization processes of micro-cracks, where primary-wave-induced E’-Center and NBOHC defects played roles of “damage precursors”. Concomitantly, transitional deformation zones containing massive strip-like-distributed cavities (similar to “immature” micro-cracks) were generated around micro-cracks. There was a cascading evolution process of point defects, cavities, and micro-cracks under phased energy input from waves, causing an anomalous “quasiplasticity” process within brittle fused silica. It differs from transient fracture processes of brittle materials. Finally, the Rayleigh waves trapped on surfaces attracted micro-cracks towards them, causing disastrous surface damage. The thermal damage originated from the volcanic vents formed within 3∼4 ns, which was induced under the comprehensive action of the impact of elastoplastic waves, cascading solid-liquid-gas phase transition, GPa-level pressure difference between ablated zones and air, and fluidic flow disturbances. The whole time-evolution sequence axis diagram of the material failure process was drawn based on these. Summarily, this work could offer novel insights into the anomalous “quasiplasticity”, spallation, and thermal damage phenomena of fused silica under intense lasers.散裂和热损伤限制了熔融二氧化硅在极强激光下的应用。在此，基于首次构建的跨尺度模型、分子动力学模拟和多模态表征，研究了不明确的潜在机制，包括极端辐照诱导的塑性相关行为。材料的散裂是由四重弹塑性波作用下微裂纹的反常“准塑性”和相扩展引起的。虽然最快的一次波不会引起宏观变形，但由于材料相变和不稳定效应，会导致微观塑性现象（环形组织转变和点缺陷扩散）。随后，共轭二次弹塑性波和头弹塑性波主导了微裂纹的初始化过程，其中初级波诱导的E′-Center缺陷和NBOHC缺陷发挥了“损伤前体”的作用。同时，在微裂纹周围形成过渡性变形带，其中含有大量条状分布空腔（类似于“未成熟”微裂纹）。在波的相位能量输入下，点缺陷、空洞和微裂纹发生级联演化过程，导致脆性石英内部出现异常的“准塑性”过程。它不同于脆性材料的瞬态断裂过程。最后，被困在表面上的瑞利波吸引了微裂缝，造成了灾难性的表面损伤。热损伤源于3 ~ 4 ns内形成的火山口，是弹塑性波冲击、级联固液气相变、烧蚀区与空气之间gpa级压差以及流体扰动综合作用的结果。在此基础上绘制了材料破坏过程的整个时间演化序列轴图。总之，这项工作可以为强激光下熔融二氧化硅的异常“准塑性”、散裂和热损伤现象提供新的见解。Wrinkling Mechanics of Immersed Magneto-active HydrogelsGuozhan Xia, Renwei Mao, Weiqiu Chen, Yipin Sudoi:10.1016/j.jmps.2025.106430浸没磁活性水凝胶的起皱力学本研究探讨了置于装有磁性溶剂的槽中的磁活性水凝胶（MAH）块体的可调褶皱现象。槽的顶部和底部各有一个电磁铁极，通过通电线圈产生均匀的磁偏置场。在非线性磁弹性理论和水凝胶非平衡热力学的框架内，建立了小振幅褶皱的力学行为模型，其中考虑了外部麦克斯韦应力的影响。通过采用表面阻抗矩阵法结合斯特罗夫公式，将褶皱起始的分岔关系解耦为对称和反对称模式。首次为具有通用自由能函数的可压缩软材料建立了紧凑形式的显式表达式。作为代表性示例，研究了广义neo-Hookean和Gent理想MAH块体。数值结果表明，渗透率小于周围环境的块体（即归一化渗透率 μ¯<1），其起皱行为与无外加磁场时基本相似，尽管在某些细节上存在细微差异。值得注意的是，对于极厚的块体，观察到了明显的起皱“突变”，这归因于块体归一化厚度相对于容器的几何约束。然而，对于渗透率较高的块体（μ¯>1），拉伸麦克斯韦应力显著破坏了系统的稳定性，导致与低渗透率块体不同的起皱模式。有趣的是，在块体同时增厚和面积扩大的过程中也可能出现起皱现象，但这种现象可能会受到几何约束的抑制。这些发现为磁活性水凝胶的行为提供了宝贵的见解，有可能推进对其理论理解和实际应用。International Journal of PlasticityA cohesive law-based fracture phase field model for microcrack initiation and propagation in shape memory alloys subjected to a cyclic loadingJunyuan Xiong, Bo Xu, Jiachen Hu, Chao Yu, Guozheng Kangdoi:10.1016/j.ijplas.2025.104557基于内聚规律的形状记忆合金微裂纹萌生与扩展断裂相场模型This study proposes a cohesive law-based fracture phase field model combined with crystal plasticity theory to elucidate the complex microcrack initiation and propagation of shape memory alloys (S MAs) subjected to cyclic loading. A traction-separation relationship that can be experimentally calibrated is incorporated into the cohesive law of the proposed model, and the degradation of the fracture toughness caused by the localized accumulation of plastic deformation (captured by the crystal plasticity theory) is quantified through a degradation function. The simulation results demonstrate that the relatively high localized accumulated plasticity (leading to a damage accumulation) and elastic energy (providing the main driving force) can lead to microcrack initiation and propagation in NiTi S MAs during cyclic loading. When both the accumulated plasticity and elastic energy are relatively high in a local region, the propagation rate of microcracks in such a region is significantly higher than that of the microcracks in other regions or with only one dominant factor (e.g., accumulated plasticity or elastic energy). The different microstructural evolutions of austenitic and martensitic NiTi S MAs induce distinct distributions and magnitudes of elastic energy and accumulated plasticity, which drive their different microcrack evolutions. The synergistic influence of elastic energy and accumulated plasticity on microcrack evolution is effectively described by the proposed model. The simulated microcrack evolution features are in qualitative agreement with the corresponding experimental results of NiTi S MAs, validating the rationality of the proposed model and providing solid support for the investigation of the crack behavior and fracture-resistant design of S MAs and their devices.结合晶体塑性理论，提出了基于内聚规律的断裂相场模型来解释形状记忆合金在循环载荷作用下的复杂微裂纹萌生和扩展过程。将可通过实验标定的牵引-分离关系纳入该模型的内聚规律，并通过退化函数量化由局部塑性变形积累引起的断裂韧性退化（由晶体塑性理论捕获）。模拟结果表明，在循环加载过程中，较高的局部累积塑性（导致损伤累积）和弹性能（提供主要驱动力）是导致NiTi s ma微裂纹萌生和扩展的主要原因。当某一局部区域的累积塑性和弹性能都较高时，该区域的微裂纹扩展速率明显高于其他区域的微裂纹扩展速率，或者只有一个主导因素（如累积塑性或弹性能）的微裂纹扩展速率明显高于其他区域。奥氏体和马氏体NiTi s ma的不同组织演化导致其弹性能和累积塑性的不同分布和大小，从而驱动其不同的微裂纹演化。该模型有效地描述了弹性能和累积塑性对微裂纹演化的协同影响。模拟的微裂纹演化特征与相应的NiTi S MAs实验结果在定性上一致，验证了所提模型的合理性，为S MAs及其器件的裂纹行为研究和抗断裂设计提供了坚实的支撑。Thin-Walled StructuresHybrid tubular joints featuring topology-optimised DED-Arc nodesMinze Zhang, Xin Meng, Wenxuan Hong, Pinelopi Kyvelou, Leroy Gardnerdoi:10.1016/j.tws.2025.114298具有拓扑优化的d - arc节点的混合管状接头Relative to conventional formative or subtractive manufacturing techniques, additive manufacturing (AM) offers increased geometric freedom, and the potential for enhanced structural efficiency and greater automation. Hybrid construction, which combines conventionally produced structural components with AM parts, is considered the most practical way to deploy metal AM in construction. This study aims to develop an optimisation methodology for hybrid tubular joints, incorporating topology optimisation and printability considerations. The studied tubular joints have an X-shaped configuration, comprising conventionally produced circular hollow section (CHS) members and wire-arc directed energy deposited (DED-Arc) nodes. The DED-Arc nodes were topology optimised, with performance and printability enhanced by imposing stress and overhang constraints, preventing the formation of overly slender elements and excessive overhang angles. The printability was further improved by manual adjustments to satisfy manufacturing requirements. The structural performance of the hybrid joints, including the initial stiffness, ultimate load-bearing capacity, ductility and material efficiency, was assessed through geometrically and materially nonlinear numerical an alyses and physical experiments on nine printed joints; five conventional X-joints were also fabricated and tested to provide benchmark results. Overall, the hybrid joints exhibited up to about 80% higher initial stiffness, 20% higher load-bearing capacity and 100% higher capacity-to-mass ratios under biaxial compression compared with the conventionally produced joints, indicating markedly enhanced structural efficiency.相对于传统的成形或减法制造技术，增材制造（AM）提供了更大的几何自由度，以及提高结构效率和更高自动化程度的潜力。混合结构将传统生产的结构部件与增材制造部件相结合，被认为是在建筑中部署金属增材制造的最实用方法。本研究旨在开发一种混合管状接头的优化方法，将拓扑优化和可打印性考虑在内。所研究的管状接头具有x形结构，包括常规生产的圆形空心截面（CHS）构件和线弧定向能沉积（ed -arc）节点。d - arc节点进行了拓扑优化，通过施加应力和悬垂约束，提高了性能和可打印性，防止了过于细长的元件和过大的悬垂角的形成。通过手动调整进一步提高印刷适性，以满足制造要求。通过几何和材料非线性数值分析及物理实验，对9个打印节点的初始刚度、极限承载能力、延性和材料效率等结构性能进行了评估；另外，还制作了5个传统的x形接头，并进行了基准测试。总体而言，与常规接头相比，混合接头在双轴压缩下的初始刚度提高了约80%，承载能力提高了20%，承载力质量比提高了100%，表明结构效率显著提高。来源：复合材料力学仿真Composites FEM
