【新文速递】2024年6月12日固体力学SCI期刊最新文章

今日更新：Composite Structures 2 篇，Composites Part A: Applied Science and Manufacturing 1 篇，Composites Part B: Engineering 4 篇，Composites Science and Technology 2 篇Composite StructuresFretting fatigue crack initiation and propagation behaviours of Ti6Al4V alloy coated by functionally graded materialCan Wang, Qi Zhao, Yunlai Zhou, Dagang Wang, Lihua Wang, Magd Abdel Wahabdoi:10.1016/j.compstruct.2024.118285功能分级材料涂层 Ti6Al4V 合金的摩擦疲劳裂纹萌发和扩展行为Fretting fatigue pertains to the behaviour of engineering components undergoing cyclic loading while in contact with each other. This intricate contact-related phenomenon often results in premature failure compared to conventional fatigue issues. Moreover, when these components operate in high-temperature atmospheres and experience high wear conditions, such as the heat transfer tubes in the nuclear reactor, the application of Functionally Graded Material (FGM) coatings becomes essential. Consequently, it is imperative to investigate how FGM coatings influence the initiation and propagation behaviour of fretting fatigue cracks. This paper employs the Critical Plane (CP) Method to calculate the damage parameter. Additionally, Linear Elastic Fracture Mechanics (LEFM) criteria, specifically the Extended Maximum Tangential Stress (E-MTS) criterion, are utilized to examine how FGM coatings affect the paths of crack propagation in the presence of fretting conditions. Meanwhile, due to the unavailability of material properties for FGM coatings, the damage parameter and stress intensity factors are utilized to indirectly assess the effect of FGM coatings on crack initiation and propagation lifetime. The FGM coating significantly influences tangential stress, thereby affecting the length of the stick zone, while having minimal impact on the distribution of normal stress along the contact surface. Furthermore, it is observed that adjusting the descent ratio of FGM coatings and the elastic modulus of the first FGM coating layer provides a potential avenue for enhancing both crack initiation and propagation lifetimes.摩擦疲劳是指工程部件在相互接触时承受循环载荷的行为。与传统的疲劳问题相比，这种错综复杂的接触相关现象往往会导致过早失效。此外，当这些部件在高温环境中工作并经历高磨损条件时，如核反应堆中的传热管，功能分级材料（FGM）涂层的应用就变得至关重要。因此，研究 FGM 涂层如何影响摩擦疲劳裂纹的起始和扩展行为势在必行。本文采用临界平面 (CP) 法计算损伤参数。此外，本文还利用线性弹性断裂力学（LEFM）准则，特别是扩展最大切向应力（E-MTS）准则，来研究 FGM 涂层如何影响存在微裂纹条件下的裂纹扩展路径。同时，由于无法获得 FGM 涂层的材料属性，因此利用损伤参数和应力强度因子来间接评估 FGM 涂层对裂纹起始和扩展寿命的影响。FGM 涂层对切向应力的影响很大，因此会影响粘滞区的长度，而对沿接触面的法向应力分布的影响却很小。此外，通过观察还发现，调整 FGM 涂层的下降率和第一层 FGM 涂层的弹性模量为提高裂纹萌生和扩展寿命提供了潜在的途径。Three-dimensional aggregate modelling method and damage analysis of recycled aggregate concreteJingwei Ying, Yujun Jian, Xiaojie Gan, Baixi Chen, Jianzhuang Xiaodoi:10.1016/j.compstruct.2024.118286再生骨料混凝土的三维骨料建模方法和损伤分析A new aggregate placement algorithm has been developed that can automatically identify the remaining space after the aggregate is placed, and only new aggregates are placed in these spaces. This results in a reduction in the number of overlaps with existing aggregates, and the more aggregates placed, the higher the efficiency. This method is suitable for various types of concrete, such as ordinary aggregate concrete, recycled aggregate concrete (RAC), and fiber-reinforced concrete. Finite element analysis is applied to simulate stress and damage evolution in mesoscale models of concrete, taking into account the effects of actual aggregate slenderness ratio, concavity, flatness, asymmetry ratio, and compaction degree. The study reveals that tensile damage is the primary factor in concrete damage evolution up to peak stress, with both tensile and compressive damages influencing the post-peak behavior. In RAC, older Interfacial Transition Zones (ITZs) are found to be more susceptible to early damage than newer ones. Moreover, the model effectively illustrates the influence of recycled aggregate content and concavity on concrete’s mechanical properties. This mesoscale concrete modeling method, as developed in this study, holds potential for future research on various types of concrete.我们开发了一种新的集料放置算法，可以自动识别集料放置后的剩余空间，并只在这些空间中放置新的集料。这样就减少了与现有骨料重叠的数量，而且骨料放得越多，效率就越高。这种方法适用于各种类型的混凝土，如普通骨料混凝土、再生骨料混凝土（RAC）和纤维增强混凝土。考虑到实际骨料细长比、凹度、平整度、不对称比和压实度的影响，应用有限元分析模拟混凝土中尺度模型的应力和损伤演变。研究结果表明，拉伸损伤是峰值应力前混凝土损伤演变的主要因素，拉伸和压缩损伤都会影响峰值后的行为。在 RAC 中，发现老的界面过渡区（ITZ）比新的界面过渡区更容易受到早期破坏的影响。此外，该模型还有效说明了再生骨料含量和凹度对混凝土力学性能的影响。本研究中开发的这种中尺度混凝土建模方法，为未来各类混凝土的研究提供了可能。Composites Part A: Applied Science and ManufacturingFabrication and mechanical properties of a high-performance PEEK-PEI hybrid multilayered thermoplastic matrix composite reinforced with carbon fiberSebastian Andrés Toro, Carlos González, Juan P. Fernández-Blázquez, Alvaro Ridruejodoi:10.1016/j.compositesa.2024.108308用碳纤维增强的高性能 PEEK-PEI 混合多层热塑性基复合材料的制造和力学性能This paper presents a method for manufacturing a hybrid matrix composite material reinforced with a woven carbon fiber that combines the properties of two thermoplastic polymers: PEEK (polyether-ether-ketone) and PEI (polyether-imide). The manufacturing process involves a multilayer architecture and a single hot-pressing consolidation step. Experimental tests—including uniaxial tensile tests, delamination tests in Mode I and impact tests at low velocities—were conducted to compare the resulting laminate with single matrix materials (PEEK/CF and PEI/CF).The improvements in strain to failure by 48 % in tensile tests with fiber orientation at ± 4 5 ∘ and in delamination force by 13 % in low velocity impact tests with respect to PEI/CF show that the heterogeneous matrix blend maintains the crystalline content and excellent elastoplastic response of PEEK while taking advantage of the affordability, lower processing temperature and toughness of PEI.本文介绍了一种用编织碳纤维增强的混合基复合材料的制造方法，该材料结合了两种热塑性聚合物的特性：PEEK（聚醚醚酮）和 PEI（聚醚酰亚胺）。制造工艺包括多层结构和单一的热压固结步骤。实验测试包括单轴拉伸测试、模式 I 分层测试和低速冲击测试，以比较由此产生的层压材料与单基体材料（PEEK/CF 和 PEI/CF）。与 PEI/CF 相比，纤维取向为 ± 4 5 ∘ 的拉伸试验中的破坏应变提高了 48%，低速冲击试验中的分层力提高了 13%，这表明异质基质混合物保持了 PEEK 的结晶含量和优异的弹塑性响应，同时利用了 PEI 的经济性、较低的加工温度和韧性。Composites Part B: EngineeringStructural fuses in composite structures:Engineered crack paths in carbon fibre-reinforced polymersM.Erfan Kazemi, Victor Medeau, Lorenzo Mencattelli, Emile Greenhalgh, Soraia Pimenta, James Finlayson, Silvestre T. Pinhodoi:10.1016/j.compositesb.2024.111604复合材料结构中的结构熔丝：碳纤维增强聚合物中的工程裂纹路径We designed engineered carbon fibre-reinforced polymer (CFRP) solutions for realising structural fuses in real CFRP composite components. We developed various concepts of engineered crack paths containing micro-cut patterns (MCPs) aiming to investigate how we can engage and trigger various damage propagation mechanisms both in-plane and through-the-thickness. To this end, we chose ultra-thin CFRP prepregs and engraved various designed MCPs / crack path combinations on them during layup with the help of a laser micro-machining system. Then, we manufactured CFRP specimens containing engineered crack paths and characterised them under a 3-point bending (3PB) test to evaluate their response in an out-of-plane loading scenario. We investigated various design parameters of the developed MCPs through 9 studies to understand how various parameters determine the damage propagation mechanisms and what effect they have on fracture properties. Following this, we performed fractography analysis to observe the failure mechanisms triggered by the implemented MCPs / crack path combinations in the tested specimens. The results demonstrate that carefully designed MCPs can tailor the failure load and energy dissipation, and moreover, provide significant control over the fracture locus and path.我们设计了工程碳纤维增强聚合物（CFRP）解决方案，以实现实际 CFRP 复合材料部件的结构融合。我们开发了各种包含微切割图案（MCP）的工程裂纹路径概念，旨在研究如何在平面内和厚度内参与和触发各种损伤传播机制。为此，我们选择了超薄 CFRP 预浸料，并在铺层过程中借助激光微加工系统在上面雕刻出各种设计的 MCP/裂纹路径组合。然后，我们制造了包含工程裂纹路径的 CFRP 试样，并在三点弯曲 (3PB) 试验中对其进行了表征，以评估它们在平面外加载情况下的响应。我们通过 9 项研究调查了所开发 MCP 的各种设计参数，以了解各种参数如何决定损坏传播机制以及它们对断裂性能的影响。随后，我们进行了断口成像分析，以观察在测试试样中实施的 MCP/裂纹路径组合所引发的破坏机制。结果表明，精心设计的 MCP 可以调整破坏载荷和能量耗散，而且还能对断裂位置和路径进行有效控制。Predicting Rapid Growth Behavior in Solidified Eutectic Ceramic Composites Using Infrared Thermal Imaging and Thermal Field Simulation During Laser Directed Energy DepositionZhonglin Shen, Haijun Su, Hao Jiang, Yuan Liu, Di Zhao, Yinuo Guo, Yang Cao, Minghui Yu, Peixin Yang, Xiang Li, Dong Dong, Min Guo, Zhuo Zhangdoi:10.1016/j.compositesb.2024.111619利用红外热成像和热场模拟预测激光定向能沉积过程中凝固共晶陶瓷复合材料的快速生长行为Cylindrical Al2O3/GdAlO3 binary in situ oxide eutectic ceramic composite, with a glossy surface and high relative density, has been fabricated using the laser directed energy deposition method (LDED) with optimized process parameters. In a novel and innovative approach, infrared thermal imaging and the finite element method (FEM) have been combined for the first time to capture the temperature field distribution across different regions of the molten pool during the LDED processing of the binary oxide eutectic ceramic composite, thereby synergistically obtaining the solidification characteristics. With an increase in the scanning rate, the temperature gradient within the molten pool decreases from 3.38 × 105 K/m to 1.62 × 105 K/m, while it shows minimal variation with fluctuations of the laser power. Under the conditions of high temperature gradients and rapid non-equilibrium solidification characteristic of LDED, the Al2O3/GdAlO3 (GAP) binary eutectic ceramic composites, which exhibit typical high melting entropy and faceted/non-faceted growth modes, exhibit complex and variable microstructure morphology. A combination of regular/irregular models, including JH (Jackson-Hunt), MK (Magnin-Kurz), GK (Guzik-Kopyciński) and TMK (Trivedi-Magnin-Kurz), is employed to investigate and predict the growth and transformation of microstructures. The JH and TMK models fairly predict the rod-like regular eutectic microstructure inside the colony and lamellar regular eutectic within adjacent layers, respectively. The "Chinese-script" irregular microstructure at the interface between the colony and the layers is consistent with the MK and GK models. The as-deposited eutectic ceramic composite presents ultra-fine microstructures, clear and strongly bonded phase interfaces with low strain energy, contributing to its microstructure stability after high temperature heat treatment at 1773 K for 200 hours, ans achieving a minimum microstructure coarsening rate of 0.0005 μm/h.利用激光定向能沉积法（LDED）和优化的工艺参数，制造出了表面光亮、相对密度高的圆柱形 Al2O3/GdAlO3 二元原位氧化共晶陶瓷复合材料。在二元氧化物共晶陶瓷复合材料的 LDED 加工过程中，红外热成像和有限元法（FEM）首次结合起来捕捉熔池不同区域的温度场分布，从而协同获得凝固特性。随着扫描速率的增加，熔池内的温度梯度从 3.38 × 105 K/m 减小到 1.62 × 105 K/m，而其随激光功率波动的变化极小。在 LDED 特有的高温梯度和快速非平衡凝固条件下，Al2O3/GdAlO3（GAP）二元共晶陶瓷复合材料表现出典型的高熔熵和面状/非面状生长模式，并呈现出复杂多变的微观结构形态。我们采用了规则/不规则模型组合，包括 JH（Jackson-Hunt）、MK（Magnin-Kurz）、GK（Guzik-Kopyciński）和 TMK（Trivedi-Magnin-Kurz），来研究和预测微结构的生长和转变。JH 和 TMK 模型分别较好地预测了菌落内部的棒状规则共晶微观结构和相邻层内的片状规则共晶微观结构。菌落和层之间界面的 "中国式 "不规则微观结构与 MK 和 GK 模型一致。沉积后的共晶陶瓷复合材料呈现出超精细的微观结构，相界面清晰且结合牢固，应变能较低，这有助于其在 1773 K 高温热处理 200 小时后的微观结构稳定性，并实现了 0.0005 μm/h 的最小微观结构粗化率。Selective localization of carbonized polymer dots in amorphous phase towards high breakdown strength and energy density of PVDF-based dielectric compositesZhen-jie Lu, Wen-jin Hu, Xiao-dong Qi, De-xiang Sun, Yong Wang, Jing-hui Yangdoi:10.1016/j.compositesb.2024.111627 非晶相中碳化聚合物点的选择性定位，实现基于 PVDF 的电介质复合材料的高击穿强度和能量密度In a general way, there is a contradictory between dielectric constant () and breakdown strength () in dielectric materials, and improving the discharge energy density () of dielectric polymers has become a great challenge. The semicrystalline ferroelectric polymer polyvinylidene fluoride (PVDF) is favored for its high , but its relatively weak in amorphous regions makes it still difficult to obtain appreciable . In response to the fact that the current method of introducing rigid chain amorphous polymers into the amorphous regions of PVDF has limited capability to enhance its , in this work, due to the crystallization induced phase separation, carbonated polymer dots (CPDs) as well as PMMA were introduced into the amorphous region of PVDF, and CPDs/PVDF/PMMA composites were prepared towards high and . It is confirmed that, CPDs significantly increase the entanglement density of molecular chains in amorphous regions of PVDF; in addition, CPDs rely on their inorganic carbon cores with unique electrical properties to resist carrier migration in amorphous regions of PVDF under high electric fields. In brief, CPDs are used as a reinforcing agent for the amorphous region of PVDF to further enhance its and . The composite loaded with 0.1 wt% CPDs exhibits the superior of 12.4 J/cm3 at the of 652.0 MV/m. This work provides new understanding on the dielectric response of ultrasmall-sized CPDs on polymer dielectrics, which could help us design new dielectric polymer composites with suppressed segmental motions for high breakdown strength and high energy density applications.一般来说，介电材料的介电常数（）和击穿强度（）之间存在矛盾，提高介电聚合物的放电能量密度（）已成为一个巨大的挑战。半结晶铁电聚合物聚偏二氟乙烯（PVDF）因其较高的介电常数（）和击穿强度（）而备受青睐，但由于其在无定形区的击穿强度相对较弱，因此仍难以获得可观的介电常数（）和击穿强度（）。针对目前在 PVDF 非晶区引入刚性链非晶态聚合物的方法对提高其Ⅴ-Ⅴ性能的作用有限这一事实，在这项工作中，由于结晶引起的相分离，在 PVDF 非晶区引入了碳化聚合物点（CPDs）和 PMMA，并制备出了具有高Ⅴ-Ⅴ性能的 CPDs/PVDF/PMMA 复合材料。研究证实，CPDs 能显著提高 PVDF 非晶区分子链的缠结密度；此外，CPDs 还能依靠其无机碳核的独特电学特性，在高电场下抵抗 PVDF 非晶区的载流子迁移。简而言之，CPD 可用作 PVDF 无定形区的增强剂，以进一步增强其性能。负载了 0.1 wt% CPDs 的复合材料在 652.0 MV/m 的电场中表现出 12.4 J/cm3 的优异性能。这项研究对超小尺寸 CPD 在聚合物电介质上的介电响应有了新的认识，有助于我们设计出具有抑制分段运动的新型聚合物电介质复合材料，以实现高击穿强度和高能量密度应用。Composites Science and TechnologyLayer-by-layer reconstruction of fatigue damages in composites from thermal images by a Residual U-NetBenedict von Houwald, Ali Sarhadi, Christian Eitzinger, Martin A. Ederdoi:10.1016/j.compscitech.2024.110712 利用残余 U-Net 通过热图像逐层重建复合材料中的疲劳损伤In this paper a deep learning model is used to fully reconstruct the 3D distribution of arbitrarily shaped subsurface fatigue damages in a fiber/epoxy composite from synthetic thermal surface images. Synthetic thermal surface images (TIs) of self-heating damage hotspots are produced by thermal finite element analysis which are consequently used to train a Residual U-Net based on recent architectures designed for image segmentation. Different augmentation techniques are employed to mitigate the computational cost of generating training data through thermal finite element analysis. The Residual U-Net model accurately reconstructed – layer by layer – the ground truths and thereby enabling the quantitative assessment of location, size, shape, depth and gradient of an internal fatigue damage distribution. Moreover, the Residual U-Net achieved good predictions for a comparatively small training set sizes.本文采用深度学习模型，从合成热表面图像中全面重建纤维/环氧树脂复合材料中任意形状的次表面疲劳损伤的三维分布。自加热损伤热点的合成热表面图像（TI）是通过热有限元分析生成的，因此可用于训练基于最新图像分割架构设计的残差 U-网络。我们采用了不同的增强技术，以降低通过热有限元分析生成训练数据的计算成本。残差 U-Net 模型逐层准确地重建了地面真相，从而能够对内部疲劳损伤分布的位置、大小、形状、深度和梯度进行定量评估。此外，残余 U-Net 还能在相对较小的训练集中实现良好的预测。Multiscale analysis of the compressive behaviour of polymer-based composites reinforced by hybrid Al2O3/Al fibresHao Tang, Jiaqi Xu, Aleksey B. Rogov, Constantinos Soutis, Aleksey Yerokhindoi:10.1016/j.compscitech.2024.110718 用 Al2O3/Al 混合纤维增强聚合物基复合材料抗压性能的多尺度分析Metal fibre reinforcements to polymer matrix composites (PMCs) bolster architectural flexibility and functionality affordably but feature a relatively weak interfacial bonding if not surface treated. This work demonstrates that Plasma Electrolytic Oxidation is promising to prepare woven hybrid Al2O3/Al reinforcements for PMCs. The compressive behaviour (a critical design parameter in structural design) of PMCs reinforced by ∼9 to 13 vol% γ-Al2O3/Al fibres with different oxide-to-metal ratios (∼20-50 vol%) is evaluated. The majority of fibres with the oxide ratio of 20% failed in micro-buckling mode at interlacing points. Compared to Al reinforcements, the hybrid Al2O3/Al fibres increased the specific compressive strength (σc/ρ) and modulus (Ec/ρ) of the composite by ∼15% and ∼58%, respectively. Oxide shells thicker than 15-20 μm limited further enhancement due to fibre failure by shear-induced rupture. Thinner shells on Al reinforcements are recommended for PMCs used to manufacture structural components in mechanical engineering applications.在聚合物基复合材料（PMC）中加入金属纤维增强材料可提高结构的灵活性和功能性，但如果不进行表面处理，界面结合力会相对较弱。这项研究表明，等离子电解氧化法有望为 PMC 制备出 Al2O3/Al 混合编织增强材料。研究评估了由不同氧化物金属比（20-50%）的 9 至 13 Vol% γ-Al2O3/Al 纤维增强的 PMC 的抗压性能（结构设计中的关键设计参数）。大多数氧化物比率为 20% 的纤维在交错点处以微屈曲模式失效。与铝增强材料相比，Al2O3/铝混合纤维使复合材料的抗压强度（σc/ρ）和模量（Ec/ρ）分别提高了 15% 和 58%。厚度超过 15-20 μm 的氧化壳限制了进一步的增强，因为纤维会因剪切力而断裂。建议在机械工程应用中用于制造结构部件的聚甲基丙烯酸甲酯上使用更薄的铝加固壳。来源：复合材料力学仿真Composites FEM