【新文速递】2024年9月28日固体力学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 3 篇，International Journal of Plasticity 2 篇，Thin-Walled Structures 4 篇International Journal of Solids and StructuresCharacterizing and modeling the wide strain rate range behavior of air-filled open-cell polymeric foamXinghao Wang, Zhibo Du, Jiarui Zhang, Yue Kang, Chenxu Liu, Tian Ma, Zhanli Liudoi:10.1016/j.ijsolstr.2024.113155充气开孔聚合物泡沫的宽应变速率范围特性表征与建模Air-filled open-cell polymeric foams are widely used for absorbing impact energy under various strain rates. Modeling their compression behavior under large deformation across a wide strain rate range remains a challenge, as the air pressure is dominated by viscous effect or inertial effect at different strain rates. In this study, the compression response of air-filled open-cell polyurethane (PU) foam is characterized across a wide strain rate range from 0.0001 s−1 to 5000 s−1. The plateau stress and energy absorption properties of the foam exhibit a power-law dependency on strain rate, showing lower rate sensitivity at quasi-static rates and increased sensitivity at high strain rates. To describe the observed rate sensitivity variation, the effect of airflow resistance is quantitatively modeled and a visco-hyperelastic constitutive model considering air pressure is developed. It shows that at high strain rates, the air pressure can constitute up to 30 % of the energy absorption contribution while it is relatively negligible at quasi-static strain rates, which significantly amplifies the difference in rate sensitivity between quasi-static and high strain rates. Furthermore, a simplified semi-empirical formula is proposed to rapidly estimate the air pressure in open-cell foams at high strain rates. This formula demonstrates the mechanical response transition from open-cell to closed-cell foams with increasing strain rates. This study is meaningful for understanding the dynamic response and the energy absorption capabilities of air or fluid filled open-cell foam.充气开孔泡沫塑料被广泛用于吸收不同应变速率下的冲击能。由于在不同应变率下，空气压力主要受粘性效应或惯性效应的影响，因此在大变形、宽应变率范围内对其压缩行为进行建模仍然是一个挑战。在这项研究中，充气开孔聚氨酯（PU）泡沫的压缩响应特征是在0.0001 s−1到5000 s−1的宽应变率范围内。泡沫的平台应力和能量吸收性能与应变速率呈幂律关系，在准静态速率下表现出较低的速率敏感性，在高应变速率下表现出较高的灵敏度。为了描述观测到的速率敏感性变化，对气流阻力的影响进行了定量建模，并建立了考虑气压的粘-超弹性本构模型。结果表明，在高应变率下，空气压力可占能量吸收贡献的30% %，而在准静态应变率下，空气压力相对可以忽略不计，这显著放大了准静态应变率与高应变率之间的速率灵敏度差异。此外，提出了一种简化的半经验公式来快速估计高应变率下开孔泡沫内的空气压力。该公式显示了随应变速率的增加，从开孔泡沫到闭孔泡沫的力学响应转变。本研究对了解空气或流体填充开孔泡沫的动态响应和吸能能力具有重要意义。Journal of the Mechanics and Physics of SolidsModeling direct and converse flexoelectricity in soft dielectric rods with application to the follower loadPushkar Mishra, Prakhar Guptadoi:10.1016/j.jmps.2024.105956软介质杆的正、反挠性电建模，并应用于从动器负载Dielectric rods have been employed in various electromechanical applications, including energy harvesters and sensors. This paper develops a general framework to model large deformations in dielectric rods, considering both direct and converse flexoelectric effects. Initially, we derive the governing differential equations for a three-dimensional dielectric continuum solid to model large deformations, incorporating converse flexoelectricity. Then, we derive the equilibrium equations for the flexoelectric strain-gradient special Cosserat rod. Subsequently, we establish its constitutive relations and identify the corresponding work conjugates. To solve these governing differential equations numerically, we implement a quaternion-based numerical approach and obtain flexoelectricity-based solutions corresponding to the follower load. Moreover using these constitutive relations, we have also obtained nonlinear analytical solutions for bending under the follower load that show an excellent agreement with our numerical results. Bending under the follower load is also compared with the transverse load to understand the electric field generation. Unlike, under the application of the transverse load, where the electric field increases monotonically, for the follower load, the electric field gradually switches its sign. The role of direct and converse flexoelectric coefficients has also been examined, and several interesting conclusions have been drawn. Finally, we analyze the effect of mechanical and electrical length scale parameters. The electromechanical response from the follower load can be utilized to fabricate flexoelectric sensors for nanoelectromechanical systems.介电棒已用于各种机电应用，包括能量采集器和传感器。本文发展了一个通用的框架来模拟在介质棒的大变形，同时考虑了直接和反向挠曲电效应。首先，我们推导了三维介质连续体的控制微分方程来模拟大变形，包括反向挠性电。在此基础上，推导了挠曲电应变梯度特殊Cosserat棒的平衡方程。然后，建立了它的本构关系，并确定了相应的功共轭。为了对这些控制微分方程进行数值求解，我们实现了基于四元数的数值方法，并得到了对应于从动器负载的基于柔性电的解。此外，利用这些本构关系，我们还得到了从动件载荷作用下弯曲的非线性解析解，与数值结果非常吻合。并将从动载荷下的弯曲与横向载荷进行了比较，以了解电场的产生情况。与横向负载作用下电场单调增大不同，随动负载作用下电场逐渐变换符号。本文还研究了正挠曲电系数和反挠曲电系数的作用，得出了几个有趣的结论。最后，分析了机械和电气长度尺度参数的影响。从动件负载的机电响应可用于制造纳米机电系统的柔性电传感器。Modeling spider silk supercontraction as a hydration-driven solid-solid phase transitionVincenzo Fazio, Giuseppe Florio, Nicola Maria Pugno, Giuseppe Puglisidoi:10.1016/j.jmps.2024.105959蜘蛛丝超收缩模型为水合作用驱动的固-固相变Spider silks have attracted significant interest due to their exceptional mechanical properties, which include a unique combination of high strength, ultimate strain, and toughness. A notable characteristic of spider silk, still debated from both mechanical and functional viewpoints, is supercontraction–a pronounced contraction of up to half its original length when an unconstrained silk thread is exposed to a wet environment. We propose a predictive model for the hygro-thermo-mechanical behavior of spider silks, conceptualizing this phenomenon as a solid–solid phase transition, similar to the glass transition in rubber, but driven by humidity. As wetting increases, the system undergoes a transition, at the network scale, from a hard, highly crystalline, dry state–where the material behavior is governed by stiff chains elongated along the fiber axis–to a soft, amorphous, wet state, regulated by a rubber-like response. We model these states using a two-well free energy function dependent on molecular stretch, with transition energy modulated by humidity. Based on the methods of Statistical Mechanics, we deduce that supercontraction can be interpreted as a solid–solid phase transition. We elucidate the important role of thermal fluctuations. In particular, the decrease of the critical humidity needed for supercontraction as temperature grows results as an effect of entropic stabilization of the softer rubbery phase. Our model quantitatively predicts the observed experimental behavior, capturing the temperature dependence of humidity-induced supercontraction effects and related cooperative properties.蜘蛛丝由于其特殊的机械性能而引起了极大的兴趣，其中包括高强度，极限应变和韧性的独特组合。蜘蛛丝的一个显著特征是超收缩——当一根不受约束的丝线暴露在潮湿的环境中时，它会明显收缩到原来长度的一半，这在机械和功能上都存在争议。我们提出了蜘蛛丝的湿-热-机械行为的预测模型，将这种现象概念化为固体-固体相变，类似于橡胶中的玻璃相变，但由湿度驱动。随着润湿度的增加，系统在网络尺度上经历了一个转变，从坚硬的、高度结晶的干燥状态（材料的行为由沿着纤维轴拉长的硬链控制）到柔软的、无定形的、潮湿状态（由橡胶样的响应调节）。我们使用依赖于分子拉伸的双阱自由能函数来模拟这些状态，过渡能由湿度调节。根据统计力学的方法，我们推导出超收缩可以解释为一种固-固相变。我们阐明了热波动的重要作用。特别是，随着温度的升高，超收缩所需的临界湿度降低，这是软橡胶相熵稳定的结果。我们的模型定量地预测了观察到的实验行为，捕捉了湿度诱导的超收缩效应和相关的协同特性的温度依赖性。Multi-scale modeling of hydrogel-based concrete formed under the ambient environment and the extremely harsh environment of MarsNing Liu, Tianju Xue, Jishen Qiudoi:10.1016/j.jmps.2024.105969在环境和火星极端恶劣环境下形成的水凝胶混凝土的多尺度建模Hydrogel-based concretes (HBCs) are an emerging class of load-bearing composite materials consisting of inert particles joined together by micro-hydrogel joints. As HBCs can harden via sol-gel process and H2O phase changes under a freezing temperature and vacuum, they are suitable for future exterritorial constructions. Previous studies have demonstrated that the internal microstructure of the hydrogel joints in HBC varies significantly with curing temperature and air pressure, leading to variations in their mechanical properties. In this study, we present a new multi-scale model that quantitatively predicts the mechanical properties of HBC formed under different curing environments including Martian atmosphere. On the micro-scale, four representative joint microstructures are studied, including tubular, foamy, honeycomb, and tube-cased-foam joints. We experimentally studied and analytically derived the constitutive relationship between the joint force and displacement. Particularly, we determined the process of hydrogel skin peeling from the particle's surface of tubular joints based on force and energy equilibrium. On the macro-scale, we simplified the constitutive joint relationships in a linear parallel bond model (LPM) and employed them to quantify interparticle relationships in a discrete element method (DEM)-based HBC model. The Weibull distribution is used to consider the variation of tensile and shear strengths of the hydrogel joints in the DEM. The modeling results are not only validated with the experimentally acquired compressive stress-strain curves of HBC, but also accurately predict the combined influence of mix design and curing conditions on the mechanical properties.水凝胶基混凝土（hbc）是一类新兴的承重复合材料，由惰性颗粒通过微水凝胶接缝连接在一起。由于HBCs可以在冷冻温度和真空条件下通过溶胶-凝胶过程和H2O相变硬化，因此适合未来的域外构建。已有研究表明，HBC中水凝胶接头的内部微观结构随着养护温度和空气压力的变化而发生显著变化，从而导致其力学性能的变化。在这项研究中，我们提出了一个新的多尺度模型，可以定量预测在不同固化环境下形成的HBC的力学性能，包括火星大气。在微观尺度上，研究了管状、泡沫状、蜂窝状和管套泡沫状四种具有代表性的节理微观结构。实验研究和解析推导了关节力与位移的本构关系。特别地，我们基于力和能量平衡确定了水凝胶皮从管状接头颗粒表面剥离的过程。在宏观尺度上，我们简化了线性平行键模型（LPM）中的本构结合部关系，并利用它们在基于离散元法（DEM）的HBC模型中量化质点间关系。采用Weibull分布来考虑水凝胶节理在DEM中的抗拉强度和抗剪强度变化。建模结果不仅与实验得到的HBC压应力-应变曲线相吻合，而且准确预测了配合比设计和养护条件对HBC力学性能的综合影响。International Journal of PlasticityMultiscale computational analysis of crack initiation at the grain boundaries in hydrogen-charged bi-crystalline alpha-ironYipeng Peng, Thanh Phan, Haibo Zhai, Liming Xiong, Xiang Zhangdoi:10.1016/j.ijplas.2024.104182 含氢双晶α -铁晶界裂纹萌生的多尺度计算分析This paper presents a mesoscale concurrent atomistic–continuum (CAC) simulation of crack initiation at the atomically structured grain boundaries (GBs) in bi-crystalline BCC iron (α-Fe) charged with hydrogen (H). By retaining the atomistic GB structure evolution together with the long-range dislocation-mediated plastic flow away from the GB in one model at a fraction of the cost of full molecular dynamics (MD), CAC enables us to probe the interplay between the atomic-level H diffusion, the nanoscale GB cavitation, crack initiation, growth, as well as the dislocation activities far away from the GB. Our several main findings are: (i) a tensile strain normal to the GB plane largely promotes the H diffusion towards the GB. (ii) the plasticity-induced clustering of H atoms (PICH) is identified as an intermediate process in between the H-enhanced localized plasticity (HELP) and H-enhanced de-cohesion (HEDE). (iii) PICH significantly amplifies the local stress concentration at the GB and decreases its cohesive strengths, and (iv) the GBs with different atomic structures fail differently. In detail, the H-charged Σ3 GB fails through micro-twinning assisted void nucleation and coalescence, while the H-charged Σ9 GB fails through crack initiation and growth accompanied by dislocation emission. Compared with nanoscale molecular dynamics (MD) simulations, the mesoscale CAC models get one step closer to the experimentally measurable length scales and thus predict reasonably lower GB cohesive strengths. This research addresses one key aspect of how H impacts the GB cohesive strengths in α-Fe. It offers insights into the multiscale processes of hydrogen embrittlement (HE). Our findings highlight the importance of using concurrent multiscale models, such as a combination of CAC, crystal plasticity finite element (CPFE), and cohesive zone finite element method (CZFEM), to understand HE. This will, in turn, support the development of new strategies for mitigating HE in a variety of engineering infrastructures.本文提出了一种介观并行原子-连续体（CAC）模拟方法，用于研究双晶BCC铁（α-Fe）在氢（H）负载条件下的晶界（GB）处裂纹的萌生。通过在保持原子级GB结构演化的同时，在一个模型中利用长程位错介导的塑性流动远离GB，从而以分子动力学（MD）模拟成本的一小部分，CAC使我们能够探究原子级H扩散、纳米级GB空洞、裂纹萌生、生长以及远离GB的位错活动之间的相互作用。我们的主要发现如下：（i）垂直于GB平面的拉伸应变极大地促进了H向GB的扩散。（ii）由塑性诱导的H原子簇集（PICH）被识别为H增强局部塑性（HELP）和H增强解粘（HEDE）之间的中间过程。（iii）PICH显著放大了GB处的局部应力集中，降低了其粘结强度，（iv）具有不同原子结构的GB以不同的方式失效。具体来说，H-带电的Σ3 GB通过微孪生辅助空洞成核和合并而失效，而H-带电的Σ9 GB则通过伴随位错发射的裂纹起始和扩展而失效。与纳米尺度分子动力学（MD）模拟相比，介观尺度CAC模型更接近可实验测量的长度尺度，因此预测的GB粘结强度更合理。这项研究解决了H如何影响α-Fe GB粘结强度的一个关键方面。它为理解氢致脆化（HE）的多尺度过程提供了见解。我们的发现强调了使用并行多尺度模型（如CAC、晶体塑性有限元（CPFE）和粘结区有限元法（CZFEM）的组合）的重要性，以理解HE。这将反过来支持开发各种工程基础设施中氢致脆化（HE）的新策略。Hydrostatic pressure-mediated grain boundary smoothing and plastic deformability in high-entropy alloysZhipeng Zhang, Yao Tang, Qishan Huang, Haofei Zhoudoi:10.1016/j.ijplas.2024.104185高熵合金中静压介导的晶界平滑和塑性变形性能In the presence of intrinsic lattice distortion and local concentration waves, high-entropy alloys (HEAs) possess unique microstructures, deformation patterns of dislocations and grain boundaries (GBs), and superior mechanical properties. In contrast to traditional crystalline metals, GBs in HEAs have been revealed to exhibit spontaneous roughening behavior, which reduces their migration ability and weakens the plastic deformability of HEAs. In addition, hydrostatic pressure (HP) treatment can modify the microstructure and deformability of GBs in HEAs, leading to enhanced strength and ductility in HEAs. In the present work, we aim to investigate the effect of HP on GB structural evolution in HEAs and reveal the HP-induced enhancement of plastic deformability via molecular dynamics (MD) simulations. Using a FeNiCrCoCu alloy as an example, we have demonstrated that the initially rough GBs in the HEA samples undergo a smoothing mechanism under the application of HP. The GB smoothing mechanism depends not only on the initial GB misorientation and microstructure, but also on the temperature and GB segregation. For the <110>(113) GB, the GB roughness is featured by individual GB segments connected by atomic-scale disconnections. Under HP, the disconnections glide along the GB plane and annihilate with neighboring disconnections, reducing the roughness of the GB. For <110>(112), <110>(114), <110>(116) and <110>(223) GBs, atomic rearrangements take place in local GB segments under HP, resulting in structural adjustment and GB smoothing. These HP-induced GB smoothing mechanisms can increase the plastic deformability of GBs under shear loading. Our findings deepen the understanding of GB plasticity in HEAs and provide insights into GB engineering through HP treatment.在本征晶格畸变和局部浓度波存在的情况下，高熵合金（HEAs）具有独特的显微组织、位错和晶界变形模式以及优异的力学性能。与传统的结晶金属相比，GBs在HEAs中表现出自发的粗化行为，这降低了它们的迁移能力，削弱了HEAs的塑性变形能力。静水压力（HP）处理可以改变HEAs中GBs的微观组织和变形能力，从而提高HEAs的强度和延展性。在目前的工作中，我们的目的是研究HP对HEAs中GB结构演变的影响，并通过分子动力学（MD）模拟揭示HP诱导的塑性变形能力增强。以FeNiCrCoCu合金为例，我们证明了HEA样品中最初粗糙的gb在HP的作用下发生了平滑机制。GB平滑机制不仅取决于初始的GB错取向和微观结构，还与温度和GB偏析有关。对于<110>(113)GB， GB粗糙度的特征是由原子尺度断开连接的单个GB段。在高压下，断开沿GB平面滑动并与相邻断开湮灭，降低了GB的粗糙度。对于<110>(112)、<110>(114)、<110>(116)和<110>(223)GB， HP作用下的局部GB段发生原子重排，导致结构调整和GB平滑。这些hp诱导的光滑机制可以提高GB在剪切载荷下的塑性变形能力。我们的发现加深了对HEAs中GB塑性的理解，并通过HP处理为GB工程提供了见解。Thin-Walled StructuresParameter optimisation of piezoelectric vibration absorber in composite cylindrical shells: A multi-modal approach to mitigate stochastic vibrationYucai Zhong, Rihuan Yu, Kai Zhou, Zhenguo Zhangdoi:10.1016/j.tws.2024.112713复合材料圆柱壳压电吸振器参数优化：一种多模态方法来减轻随机振动This paper investigates the stochastic vibration mitigation of composite cylindrical shells using multi-modal piezoelectric vibration absorbers (PVAs). A novel semi-analytical method is proposed to analyse the stochastic vibration characteristics of composite cylindrical shells equipped with PVAs. The vibration behavior under stochastic excitations is determined using the modified Ritz method and the pseudo excitation method (PEM). Compared to the finite element method (FEM), the proposed model greatly enhances efficiency by eliminating the need for repeated modelling and meshing, thereby facilitating the optimization of PVAs. The effects of piezoelectric patch layout and circuit parameters on PVA performance are examined in detail using the proposed electro-mechanical model. Additionally, a multi-modal PVA design procedure, combining the semi-analytical model with a surrogate model-based optimisation algorithm, is presented. The superior stochastic vibration suppression performance of the multi-modal PVA is demonstrated by comparing the dynamic responses of the composite cylindrical shell without PVA, with single-modal PVA, and with multi-modal PVA. The proposed optimisation procedure offers a valuable approach for the design of multi-modal PVAs for stochastic vibration control of cylindrical structures.研究了多模态压电吸振器对复合材料圆柱壳随机减振的影响。提出了一种新的半解析方法来分析聚乙烯醇复合材料圆柱壳的随机振动特性。采用改进的里兹法和伪激励法确定了随机激励下的振动特性。与有限元法（FEM）相比，该模型消除了重复建模和网格划分的需要，大大提高了效率，从而便于pva的优化。利用所建立的机电模型，详细分析了压电片布局和电路参数对PVA性能的影响。此外，提出了一种多模态PVA设计程序，将半解析模型与基于代理模型的优化算法相结合。通过对比无PVA、单模态PVA和多模态PVA复合材料圆柱壳的动力响应，证明了多模态PVA优越的随机抑制振动性能。所提出的优化方法为圆柱结构随机振动控制的多模态pva设计提供了一种有价值的方法。Experimental and Numerical Study of Hysteresis Behaviour of Innovative Hybrid Steel-Timber Shear Wall SystemMojtaba Gorji Azandariani, Ali Parvari, Arvin Yaghmouri, Mehdi Vajdiandoi:10.1016/j.tws.2024.112743新型钢-木混合剪力墙体系滞回特性试验与数值研究This research presents hybrid steel-timber shear walls (HSTSWs) as an environmentally friendly and structurally efficient system. The HSTSW system provides quick and easy interchangeability of the timber components, making it adjustable and adaptable to different design needs throughout the building's lifecycle. Additionally, the incorporation of timber elements into the steel frame contributes to lateral resistance while offering an eco-friendly alternative to materials such as steel and concrete. This research includes experimental studies and numerical simulations using finite element analysis to investigate and comprehensively compare the hysteresis behavior of HSTSW and SPSW. The hysteresis behavior, ultimate load, failure modes, energy dissipation mechanisms, ultimate displacement, weight-related characteristics, and efficiency of load-carrying capacity are analyzed for both HSTSW and SPSW specimens. Comparative results with SPSW indicate that HSTSW exhibit a slightly higher ultimate load-carrying capacity and significantly greater ultimate deformation capacity. The cyclic behavior and failure modes of both systems are detailed, emphasizing the trade-off between strength and ductility in HSTSWs. Stiffness, ductility, absorbed energy, and equivalent viscous damping ratio are assessed, revealing that HSTSW absorb more energy with higher specific absorbed energy and exhibit comparable damping behavior to SPSW. Additionally, numerical modeling is employed to simulate the response of SPSW and HSTSW, and a validation process is conducted to compare numerical and experimental outcomes.本研究提出了钢-木混合剪力墙（HSTSWs）作为一种环保和结构高效的系统。HSTSW系统提供了木材组件的快速和容易的互换性，使其在整个建筑生命周期中可调节和适应不同的设计需求。此外，将木材元素结合到钢框架中有助于抵抗横向阻力，同时提供了钢和混凝土等材料的环保替代品。本研究包括实验研究和数值模拟，利用有限元分析对HSTSW和SPSW的迟滞行为进行研究和全面比较。分析了HSTSW和SPSW试件的滞回特性、极限荷载、破坏模式、能量耗散机制、极限位移、重量相关特性和承载力效率。与SPSW的对比结果表明，HSTSW的极限承载能力略高于SPSW，极限变形能力显著高于SPSW。详细介绍了两种系统的循环行为和破坏模式，强调了HSTSWs强度和延性之间的权衡。通过刚度、延性、吸收能量和等效粘性阻尼比的评估，发现HSTSW吸收更多的能量，比吸收能量更高，并且具有与SPSW相当的阻尼行为。此外，采用数值模拟方法对SPSW和HSTSW的响应进行了模拟，并对数值结果和实验结果进行了对比验证。Mechanical behavior of reinforced Al2O3 lattice structures: Effects of structural parameters from experiments and simulationsKe Zhong, Zhiguo Wang, Jin Cui, Xuehua Yu, Mingtao Zhang, Zhenfeng He, Yuhui Zhao, Jibin Zhaodoi:10.1016/j.tws.2024.112753增强Al2O3晶格结构的力学行为：结构参数对实验和模拟的影响The pressure hull is one of the core components of autonomous underwater vehicles (AUVs), necessitating a new structural material with improved mechanical and lightweight properties. For this purpose, a novel type of reinforced lattice structure (RLS) that integrates Al2O3 lattice structures (ALSs) with phenol-formaldehyde (PF) resin was designed and fabricated via stereolithography (SL)-based additive manufacturing and infiltration processes. The responses of the RLSs with different structural configurations, relative densities, and unit cell sizes under compressive loading were systematically characterized. Additionally, numerical simulations were conducted to further predict and study the mechanical behavior of the RLSs using Johnson-Holmquist-II (JH-2) model. The results revealed that the mechanical properties of the RLSs from superior to inferior were simple cubic (SC), body-centered cubic (BCC), Gyroid, octet truss (Oct), and SchwarzP (Sch). As the relative density and the unit cell size increased, the mechanical properties of the RLSs increased. Furthermore, the results of the numerical simulations closely aligned with the experimental results, which provided an in-depth analysis of internal damage and crack propagation in the RLSs under compression. A comparison of the mechanical properties also demonstrated that RLSs exhibit superior compressive strength and energy absorption performance than traditional ALSs do. After this investigation, this type of RLS is anticipated to facilitate lightweighting of AUVs, advancing the development of deep-sea scientific research.耐压壳体是自主水下航行器（auv）的核心部件之一，因此需要一种具有改进机械性能和轻量化性能的新型结构材料。为此，通过基于立体光刻（SL）的增材制造和渗透工艺，设计并制造了一种新型的增强晶格结构（RLS），该结构将Al2O3晶格结构（ALSs）与酚醛（PF）树脂相结合。系统表征了不同结构构型、相对密度和晶胞尺寸的rls在压缩载荷作用下的响应。此外，采用Johnson-Holmquist-II （JH-2）模型进行了数值模拟，进一步预测和研究了rls的力学行为。结果表明，rls的力学性能由高到低依次为简单立方（SC）、体心立方（BCC）、陀螺（Gyroid）、八元桁架（Oct）和SchwarzP （Sch）。随着相对密度和晶胞尺寸的增大，rls的力学性能增大。数值模拟结果与实验结果吻合较好，深入分析了rls在压缩作用下的内部损伤和裂纹扩展过程。力学性能的比较也表明，rls具有比传统als更好的抗压强度和能量吸收性能。通过本次研究，这种类型的RLS有望促进auv的轻量化，推动深海科学研究的发展。Macro/micro failure mechanism of transparent armour subjected to multiple impacts of 7.62mm bulletsYubo Gao, Liutong Shi, Zhihao Li, Zhe Jia, Yanxin Gedoi:10.1016/j.tws.2024.1127547.62mm子弹多重冲击下透明装甲宏微观破坏机理Transparent armor is widely used in military and civilian impact protection fields due to its excellent light transmittance and ballistic performance. This work focused on the macro/micro failure mechanisms of transparent armor for vehicles subjected to multiple impacts. Results showed that the penetration depth after the first impact by a 7.62 mm bullet is about 14 mm, regardless of the impact position. Based on the cavity expansion theory, the penetration depth under multiple projectile impacts was predicted, relating it to the distance between the impact points, the distance from the projectile hole to the edge of the target plate, and the damage radius caused by the first impact. In the thickness direction, observation of the glass layer damage modes revealed that the interlayer adhesive could hinder the propagation of vertical cracks between different glass layers, with delamination primarily caused by insufficient shear strength. In the in-plane direction, the size of the fractured glass gradually increases outward from the impact point because circumferential cracks can prevent the propagation of radial cracks. Finally, the micro failure analysis of glass fragments showed that the radial cracks are dominated by numerous irregular microcracks and river-like textures, while the circumferential cracks consist of the mirror region, mist region, hackle region, and river-like texture region.透明装甲以其优异的透光性和弹道性能，广泛应用于军用和民用防撞领域。本文主要研究了车辆透明装甲在多重冲击下的宏观/微观失效机制。结果表明，无论在何种位置，7.62 mm子弹第一次撞击后的侵彻深度约为14 mm。基于空腔膨胀理论，预测了弹丸在多次冲击下的侵彻深度，并将其与弹丸点之间的距离、弹丸孔到靶板边缘的距离以及第一次冲击造成的损伤半径联系起来。在厚度方向上，对玻璃层损伤模式的观察表明，层间胶粘剂会阻碍不同玻璃层之间垂直裂纹的扩展，导致分层的主要原因是剪切强度不足。在平面方向上，破碎玻璃的尺寸从撞击点向外逐渐增大，因为周向裂纹可以阻止径向裂纹的扩展。最后，玻璃碎片的微观破坏分析表明，径向裂纹以大量不规则微裂纹和河状织构为主，而周向裂纹则由镜像区、雾区、毛刺区和河状织构区组成。来源：复合材料力学仿真Composites FEM