【新文速递】2024年5月28日固体力学SCI期刊最新文章

今日更新：Composite Structures 5 篇，Composites Part A: Applied Science and Manufacturing 1 篇，Composites Part B: Engineering 1 篇，Composites Science and Technology 1 篇Composite StructuresDoes hygrothermal degradation of Mode I fatigue delamination resistance in carbon fibre reinforced polymer laminates depend on the ageing conditions?Liaojun Yao, Jingchao Wei, Zixian He, Yonglyu He, Stepan V. Lomov, Rene C. Alderliestendoi:10.1016/j.compstruct.2024.118240碳纤维增强聚合物层合板抗I型疲劳脱层的湿热退化是否取决于老化条件?Hygrothermal ageing has detrimental effect of the fatigue delamination growth (FDG) in carbon fibre reinforced polymer laminates, and may increase the crack growth rate by a factor of ∼5. The paper examines, how this degradation for Mode I fatigue delamination is affected by the severity of the ageing conditions. Fatigue delamination tests for R = 0.1 and R = 0.5 are conducted after ageing (1) at 70 °C 85 % relative humidity (RH) and (2) immersion in 70 °C water bath (WB). Paris-type FDG characterisation is derived, in the form, which accounts for the effect of fibre bridging. It is demonstrated that parameters of FDG degradation do not differ for these two types of hygrothermal ageing. The physical reasons for this are examined using dynamic mechanical thermal analysis (DMTA) and fractographic analysis, which revealed similar irreversible degradation of the material near the fibre/matrix interface and in the matrix itself, and the similar damage mechanisms in fatigue delamination. Furthermore, this study can highlight the importance of obeying similitude principles in FDG characterisation, and provide extra information for the ISO standard development for mode I fatigue delamination in unidirectional carbon fibre reinforced polymer composites.湿热老化对碳纤维增强聚合物层合板的疲劳脱层扩展(FDG)有不利影响，并可能使裂纹扩展速率增加约5倍。本文考察了这种退化的I型疲劳分层是如何受到老化条件的严重程度的影响。(1)在70℃85 %相对湿度(RH)和(2)在70℃水浴(WB)中浸泡后，分别进行R = 0.1和R = 0.5的疲劳分层试验。巴黎型FDG特性推导，在形式中，它说明了光纤桥接的影响。结果表明，两种类型的湿热老化对FDG的降解参数没有影响。使用动态机械热分析(DMTA)和断口分析检查了这一现象的物理原因，揭示了纤维/基体界面附近和基体本身的材料类似的不可逆降解，以及疲劳分层中类似的损伤机制。此外，该研究可以强调在FDG表征中遵循相似原则的重要性，并为单向碳纤维增强聚合物复合材料I型疲劳分层的ISO标准制定提供额外的信息。Pullout behavior of the steel-FRP composite bar with the anchor head made of the grout-filled steel tubeGang Xiao, Wei Tan, Peirong Mai, Shiwen Han, Jinping Oudoi:10.1016/j.compstruct.2024.118242以灌浆钢管为锚头的钢- frp复合筋的拉拔性能Steel-fiber reinforced polymer composite bars (SFCBs) offer a viable solution to replace steel bars in concrete structures and mitigate their corrosion issues. However, the inflexibility of SFCBs weakens their bond with concrete. This study addressed this gap by employing a steel tube connected to the end of SFCB using grout as its anchor head. Subsequent pullout tests were conducted on SFCBs with and without anchor heads, exploring variables such as SFCB diameter, anchorage length, anchor-head diameter, concrete-cover thickness, and spiral ratio. Various failure modes were observed, including SFCB rupture, and concrete cracking with and without stirrups. Anchor heads significantly enhanced the bearing capacity and bond stiffness of SFCB specimens, notably reducing splitting forces. Augmenting anchorage length and anchor-head diameter improved the bond stiffness of SFCBs in concrete. The anchor-head diameter should not be less than 2.4 times the SFCB diameter. Furthermore, an increase in concrete-cover thickness or spiral ratio notably heightened the concrete’s resistance to cracking. The contribution ratio of bond force increases with the anchorage length and decreases with the slip, SFCB diameter, and anchor-head diameter. A predictive method for determining concrete-cover thickness and spiral ratio was developed to ensure SFCB pullout specimens steer clear of concrete splitting.钢纤维增强聚合物复合棒材(sfcb)为混凝土结构中钢筋的替代和腐蚀问题的缓解提供了可行的解决方案。然而，sfcb的不灵活性削弱了它们与混凝土的结合。本研究通过使用一根钢管连接到SFCB的末端，使用浆液作为其锚头来解决这一差距。随后分别对带锚头和不带锚头的SFCB进行了拉拔试验，探索SFCB直径、锚固长度、锚头直径、混凝土覆盖厚度和螺旋比等变量。观察到各种破坏模式，包括SFCB破裂，混凝土开裂有和没有箍筋。锚头显著提高了SFCB试件的承载力和粘结刚度，显著降低了劈裂力。增加锚固长度和锚杆头直径可提高sfcb在混凝土中的粘结刚度。锚头直径应不小于SFCB直径的2.4倍。此外，混凝土覆盖层厚度或螺旋比的增加显著提高了混凝土的抗裂性。黏结力的贡献率随锚固长度的增加而增大，随滑移量、SFCB直径、锚杆头直径的增大而减小。提出了一种确定混凝土覆盖厚度和螺旋比的预测方法，以确保SFCB拉拔试件避免混凝土劈裂。The influence of temperature and placement rate on wound laminated carbon fibre/PEEK hoop specimens manufactured by in-situ consolidated LATPEmma Tobin, Aswani Kumar Bandaru, Ronan M. O’Higgins, Paul M. Weaverdoi:10.1016/j.compstruct.2024.118243温度和放置率对原位固结LATP法制备缠绕碳纤维/PEEK层合箍试样的影响The effect of laser-assisted automated tape placement (LATP) in-situ consolidation processing parameters on mechanical properties of manufactured laminates is an important consideration. In this study, a combination of placement rates and processing temperatures were assessed to determine their effects on wound laminated hoops for two carbon fibre (CF)/PEEK material systems, one with sized fibres and one without. It was found that these CF/PEEK material systems, while manufactured with the same LATP processing parameters, have different maximum interlaminar shear strengths, void growth characteristics and crystallinity levels. The results indicate that the placement rate has a statistically significant influence on the interlaminar shear strength and sample thickness. It was observed that there is a notable interaction between placement rate and processing temperature for the unsized fibre CF/PEEK system.激光辅助自动铺带(LATP)原位固结工艺参数对层压板力学性能的影响是一个重要的考虑因素。在这项研究中，评估了放置率和加工温度的组合，以确定它们对两种碳纤维(CF)/PEEK材料系统的缠绕层压箍的影响，一种是有尺寸纤维，另一种是没有尺寸纤维。结果表明，在相同的工艺参数下，CF/PEEK材料体系具有不同的最大层间剪切强度、空隙生长特性和结晶度。结果表明，填充率对层间剪切强度和试样厚度的影响具有统计学意义。研究发现，未上浆的CF/PEEK纤维体系中，放置率与加工温度之间存在显著的交互作用。Twist design of lattice structure fabricated by powder bed fusion to adjust the energy absorption behaviorLeyao Zhang, Hongshuai Lei, Fei Wang, Panding Wang, Shengyu Duan, Zeang Zhaodoi:10.1016/j.compstruct.2024.118244粉末床熔合制备晶格结构的捻度设计以调节能量吸收行为Additive manufactured lattice structures offer great potential for impact resistance applications. They exhibit excellent energy absorption characteristics during the elasto-plastic deformation process, providing protection to internal devices. However, the mechanical response of lattice structures undergoes substantial variations during the deformation process, thereby imposing limitations on their energy absorption behavior. This study introduces a novel twist design to modify the energy absorption behavior of rectangular and hollow cylindrical lattice structures. Powder bed fusion was used to fabricate the twisted lattice structures. The study employed a combination of compressive simulations and experimental investigations to systematically explore the impact of the twist angle on the peak crushing force, energy absorption, and crash load efficiency of the structures. Adjusting the twist angle results in a reduction of the peak crushing force and a transition towards a stable loading profile during the deformation process. Moreover, the crash load efficiency is also reduced. The twist design concept presented in this paper provides insight into designing and optimizing lattice structures for energy absorption applications.添加剂制造的晶格结构提供了巨大的抗冲击应用潜力。它们在弹塑性变形过程中表现出优异的能量吸收特性，为内部器件提供保护。然而，在变形过程中，晶格结构的力学响应发生了很大的变化，从而限制了它们的能量吸收行为。本文介绍了一种新的扭曲设计来改变矩形和空心圆柱晶格结构的能量吸收行为。采用粉末床熔合法制备了扭曲晶格结构。本研究采用压缩模拟与实验研究相结合的方法，系统探讨扭转角对结构峰值破碎力、能量吸收和碰撞载荷效率的影响。在变形过程中，调整扭转角度可以减少峰值破碎力，并向稳定的加载剖面过渡。此外，碰撞载荷效率也降低了。本文提出的扭曲设计概念为设计和优化能量吸收应用的晶格结构提供了见解。Micromechanical analysis of fiber-reinforced ceramic matrix composites by a geometrically nonlinear hierarchical quadrature element modelYingying Lan, Bo Liudoi:10.1016/j.compstruct.2024.118245基于几何非线性层次正交元模型的纤维增强陶瓷基复合材料细观力学分析The stress fields of fiber-reinforced ceramic matrix composites (CMCs) under longitudinal tension are predicted using a non-linear hierarchical quadrature element method (HQEM) in this work. The HQEM combines the differential quadrature method (DQM) with the hierarchical finite element method (HFEM), which is a typical p-version finite element method (FEM). High-order interpolation functions of the HQEM allow accurate evaluation of stress distribution. Fiber, matrix, and interfaces of the CMCs are modeled as linear elastic materials that may have large displacements. The nonlinear HQEM estimation of CMCs stress distributions are validated by comparing with analytical results obtained using classical BHE shear-lag model. Stress distribution in three characteristic stages in the damage evolution process, namely, interface perfectly bonded, interface debonding, and fiber failure are investigated. It is shown that when fiber failure happens, geometric non-linearity must be considered to avoid excessive stress concentration. Furthermore, the stress distribution within three-dimensional cylindrical CMCs cell is studied, which sheds light on the future exploration of three-dimensional CMCs analyses本文采用非线性层次正交元法(HQEM)预测了纤维增强陶瓷基复合材料在纵向拉伸作用下的应力场。该方法将微分正交法(DQM)与分层有限元法(HFEM)相结合，是一种典型的p型有限元法。高阶插值函数的HQEM允许准确的评估应力分布。cmc的纤维、基体和界面被建模为可能具有大位移的线弹性材料。通过与经典BHE剪切滞后模型的分析结果对比，验证了cmc应力分布的非线性HQEM估计。研究了损伤演化过程中界面完全粘结、界面脱粘和纤维破坏三个特征阶段的应力分布。研究表明，当纤维发生破坏时，必须考虑几何非线性，以避免过度的应力集中。此外，本文还研究了三维圆柱形cmc胞内的应力分布，为进一步探索三维cmc分析提供了理论依据Composites Part A: Applied Science and ManufacturingNovel bio-inspired design strategy for balancing of strength/toughness/random defect tolerance of compositeYansong Shi, Jiawen Zeng, Qiang Zhang, Zuoqi Zhang, Yanan Yuandoi:10.1016/j.compositesa.2024.108286复合材料强度/韧性/随机缺陷容忍度平衡的新型仿生设计策略The shells exhibit exceptional mechanical properties, characterized by significantly higher strength and toughness compared to its constituent materials. This remarkable mechanical behavior is attributed to its microstructure. In the struggle for survival against mantis shrimps, shells are inevitably introduced into random defects, yet these do not compromise its impact resistance properties. This is because the brick–mortar microstructure exhibits excellent defect-insensitivity compared to continuous fiber structures, despite its significantly lower strength. We are considering whether it is feasible to design a new microstructure capable of simultaneously possessing outstanding defect-insensitive properties and high strength/toughness characteristics. Therefore, this paper innovatively proposes a hybrid design strategy for various microstructures. Python script codes were generated to model brick–mortar with varying slenderness ratios including the initial defects. Experiment was also conducted to verify the effective of finite element model. Results shown that Hybrid-1 structure distinguishes itself with the high peak load & damage dissipation energy and excellent defect-insensitive among the designed structures. The defect-insensitive characteristic of damage dissipation energy in Hybrid-2 even surpasses that of the uniform brick-and-mortar structure, while it maintains strength levels nearly equivalent to those of continuous fibers. This hybrid design strategy demonstrates significant potential in achieving a balance among strength, toughness, and tolerance to random defects in microstructures, offering new avenues for biomimetic design in composite materials.外壳具有优异的机械性能，其特点是与其组成材料相比具有更高的强度和韧性。这种显著的力学性能归因于其微观结构。在与螳螂虾的生存斗争中，炮弹不可避免地引入随机缺陷，但这些并不影响其抗冲击性能。这是因为与连续纤维结构相比，砂浆结构表现出优异的缺陷不敏感性，尽管其强度明显较低。我们正在考虑是否有可能设计一种新的微观结构，能够同时具有出色的缺陷不敏感性能和高强度/韧性特性。因此，本文创新性地提出了一种针对多种微结构的混合设计策略。生成Python脚本代码来模拟具有不同长细比的砂浆，包括初始缺陷。通过实验验证了有限元模型的有效性。结果表明，Hybrid-1结构具有较高的峰值荷载和损伤耗散能以及较好的缺陷不敏感性。Hybrid-2的损伤耗散能的缺陷不敏感特性甚至超过了均匀砂浆结构，而其强度水平几乎与连续纤维相当。这种混合设计策略在实现强度、韧性和对微观结构随机缺陷的容忍度之间的平衡方面显示出巨大的潜力，为复合材料的仿生设计提供了新的途径。Composites Part B: EngineeringEngineering Digital Light Processing Ceramic Composites for Wide-Range Flexible Sensing ArraysDongsu Lee, Dong Hwi Kim, Hyungyong Kim, Hong Min Seung, Hyun-Cheol Song, Miso Kimdoi:10.1016/j.compositesb.2024.111595 用于大范围柔性传感阵列的工程数字光处理陶瓷复合材料Flexible ceramic composites are promising candidates in capacitive pressure sensing applications. However, the fabrication of complex composite structures typically involves costly and time-consuming processes such as lithography or mold utilization. Digital light processing (DLP)-based 3D printing offers a layer-by-layer approach via photopolymerization, facilitating rapid prototyping of various ceramic composite structures in a single-step synthesis process. This study presents the successful implementation of a flexible ceramic composite based on the highly dielectric ceramic BaTiO3 and conductive MWCNT fillers by employing DLP 3D printing to create an hourglass-shaped stress concentration structure, aiming at enhancing flexible capacitive sensing capabilities. Blending commercial flexible resin with 4-acryloyl morpholine monomers yields a photocurable resin formulation with appropriate mechanical flexibility, photocurability, and optimal suspension viscosity suitable for DLP 3D printing. Furthermore, the proposed 3D-printed sensor arrays comprising hourglass-shaped unit cells demonstrate improved linear sensitivity across a broad pressure range owing to efficient stress concentration effects in a symmetric geometry, as corroborated by both finite element methods and experiments. DLP 3D printing, combined with tailored resin formulations and optimized ceramic and conductive filler contents, enables the rapid prototyping of diverse sensor structures with significantly enhanced sensitivity, highlighting the versatility of this approach for a wide range of applications.柔性陶瓷复合材料在电容式压力传感领域具有广阔的应用前景。然而，复杂复合结构的制造通常涉及昂贵和耗时的过程，如光刻或模具的使用。基于数字光处理(DLP)的3D打印通过光聚合提供了一种逐层方法，促进了在单步合成过程中快速成型各种陶瓷复合结构。本研究成功实现了基于高介电陶瓷BaTiO3和导电MWCNT填料的柔性陶瓷复合材料，采用DLP 3D打印技术创建了沙漏形应力集中结构，旨在增强柔性电容传感能力。将商业柔性树脂与4-丙烯酰啉单体混合，可获得光固化树脂配方，具有适当的机械柔韧性、光固化性和最佳悬浮粘度，适合DLP 3D打印。此外，所提出的由沙漏形单元组成的3d打印传感器阵列，由于对称几何结构中有效的应力集中效应，在宽压力范围内表现出更高的线性灵敏度，这一点得到了有限元方法和实验的证实。DLP 3D打印，结合定制的树脂配方和优化的陶瓷和导电填料内容，使各种传感器结构的快速原型设计具有显着增强的灵敏度，突出了这种方法的多功能性，适用于广泛的应用。Composites Science and TechnologyStrengthening and toughening of hard epoxy vitrimer nanocomposites with interfacial covalent binding and microphase separationZhiqiang Chen, Zhen Li, Xubin Wang, Chenyu Jin, Dichao Ningdoi:10.1016/j.compscitech.2024.110684 界面共价结合微相分离的硬质环氧树脂纳米复合材料的强化增韧研究Vitrimers with dynamic covalent bonds combine the merits of thermosets and thermoplastics, opening up new opportunities for science and industry. The attainment of enhanced mechanical performance without compromising dynamic reprocessability poses a significant obstacle to vitrimer materials. Designing vitrimer nanocomposites from interfacial and structural aspects is promising to solve this problem. Herein, strengthening and toughening of hard epoxy vitrimer using nanosilica have been successfully achieved by introducing interfacial covalent binding and microphase separation. Performing interfacial covalent binding between epoxide-modified silica nanoparticles and hard epoxy vitrimer matrix improves interfacial compatibility and nanoparticle dispersion. Controlling the proportion of silica nanoparticles yields two types of microstructures, including a uniformly dispersed material at low nanoparticle loadings and unique microphase separation at high nanoparticle loadings. Particularly, silica reinforcement accompanied with phase separation exhibits a substantial enhancement in Young’s modulus, tensile strength, and fracture toughness while achieving good stretchability. In addition, the silica-epoxy vitrimer nanocomposites preserve excellent reprocessability not inferior to the pristine vitrimer. The resulting nanocomposites show potential applications in bonding, recycling, and shape morphing. The concepts and methodologies presented in this work will enlighten future vitrimer material design.具有动态共价键的玻璃体结合了热固性和热塑性塑料的优点，为科学和工业开辟了新的机会。在不影响动态再加工性能的情况下获得增强的机械性能是玻璃体材料的一个重大障碍。从界面和结构两方面设计玻璃聚合物纳米复合材料有望解决这一问题。本文通过引入界面共价结合和微相分离，成功实现了纳米二氧化硅对硬质环氧玻璃体的强化增韧。环氧改性二氧化硅纳米颗粒与硬质环氧玻璃体基体之间的界面共价结合改善了界面相容性和纳米颗粒的分散。控制二氧化硅纳米颗粒的比例可以产生两种类型的微观结构，包括低纳米颗粒负载时均匀分散的材料和高纳米颗粒负载时独特的微相分离。特别是，伴随着相分离的二氧化硅增强在杨氏模量、拉伸强度和断裂韧性方面表现出了显著的提高，同时获得了良好的拉伸性。此外，二氧化硅-环氧玻璃体纳米复合材料保持了优异的再加工性能，不逊于原始玻璃体。由此产生的纳米复合材料在键合，回收和形状变形方面具有潜在的应用前景。这项工作中提出的概念和方法将启发未来的玻璃材料设计。来源：复合材料力学仿真Composites FEM