Composite Structures最新文献_第2页

Investigation on the recycling potential of additively manufactured carbon fiber reinforced PA 6.6 关于加成型碳纤维增强 PA 6.6 回收潜力的研究

IF 6.3 2区材料科学 Q1 MATERIALS SCIENCE, COMPOSITES

Composite Structures

Pub Date : 2024-11-08 DOI: 10.1016/j.compstruct.2024.118683

C. Lohr , A. Trauth , J. Schukraft , S. Leher , K.A. Weidenmann

Carbon fiber reinforced polymers (CFRP) are already used in a wide range of applications such as automotive, aerospace and renewable energy industries and demand on this material class is increasing steadily. As demand increases, the amount of CFRP waste, either from production or at the end of life of components, increases simultaneously and sustainable solutions such as disposal, reuse or recycling of fiber reinforced materials getting more and more important.

In this paper one possibility for recycling short carbon fiber reinforced polyamide 6.6 (CF/PA 6.6) is presented. The recycling process includes shredding of the material, drying and filament extrusion to enable a reuse of the material with an additive manufacturing process. The focus of this investigation is on the mechanical properties of the recycled filaments itself as well as on the 3D printed specimen considered recycled filaments. The properties at different stages of the short carbon fiber reinforced polyamide 6.6 recycling process were investigated, including the juvenile CF/PA 6.6 as well as specimens made from one- or two-times recycled material. Mechanical performance was evaluated by tensile, bending and impact testing. Experimental results pointed out that no significant difference in performance of juvenile and recycled materials was observed for tensile and flexural loads. The impact strength of the recycled specimen decreased to a small extent.

碳纤维增强聚合物（CFRP）已被广泛应用于汽车、航空航天和可再生能源等行业，对这一类材料的需求也在稳步增长。随着需求的增加，碳纤维增强塑料（CFRP）在生产过程中或部件报废时产生的废料量也随之增加，因此纤维增强材料的处置、再利用或回收等可持续解决方案变得越来越重要。回收过程包括材料粉碎、干燥和长丝挤压，以便通过增材制造工艺实现材料的再利用。本次研究的重点是再生长丝本身以及考虑了再生长丝的 3D 打印试样的机械性能。研究了短碳纤维增强聚酰胺 6.6 回收过程中不同阶段的性能，包括幼体 CF/PA 6.6 以及由一次或两次回收材料制成的试样。机械性能通过拉伸、弯曲和冲击测试进行评估。实验结果表明，在拉伸和弯曲载荷下，未加工材料和回收材料的性能没有明显差异。再生试样的冲击强度略有下降。

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引用次数: 0

Experimental and numerical investigations of interlaminar shear behaviors of CFRP composites at cryogenic and high temperatures 低温和高温条件下 CFRP 复合材料层间剪切行为的实验和数值研究

IF 6.3 2区材料科学 Q1 MATERIALS SCIENCE, COMPOSITES

Composite Structures

Pub Date : 2024-11-07 DOI: 10.1016/j.compstruct.2024.118681

W.J. Huang , Y.T. Li , Y.M. Zhang , Z.M. Xiao , W.G. Li

The interlaminar shear strength and failure modes of carbon fiber reinforced polymer composites at different temperatures ranged from 90 K to 353 K were thoroughly investigated by the short beam shear tests. Considering the three different lay-up configurations, i.e., unidirectional, cross-ply and angle-ply, the results showed that the interlaminar shear strength of the unidirectional laminates increased by 67.5 % with the decrease of temperature from room temperature down to 90 K, while they were insignificantly affected by cryogenic temperature for both the cross-ply and angle-ply laminates. A numerical model of short beam shear behavior was developed to calculate the interlaminar shear strength, and the results were found to be in a good agreement with the experimental data. Furthermore, the observations of fracture surfaces using a scanning electron microscope provided the insights into the failure modes of the laminates at the microscopic scale. At 90 K the delamination in the unidirectional laminates was obvious, extending toward to the edge of the specimen. In the cross-ply laminates, a few large penetrating cracks appeared in the mid-plane, several small matrix cracks and voids were obvious in the fracture surface of the specimen. Additionally, the multiple cracks formed by the delamination were observed in the angle-ply laminates.

通过短梁剪切试验，深入研究了碳纤维增强聚合物复合材料在 90 K 至 353 K 不同温度下的层间剪切强度和破坏模式。结果表明，单向层压板的层间剪切强度随着温度从室温降至 90 K 而增加了 67.5%，而交叉层压板和角层压板的层间剪切强度受低温影响不大。为了计算层间剪切强度，我们建立了一个短梁剪切行为数值模型，结果发现与实验数据非常吻合。此外，通过扫描电子显微镜对断裂表面的观察，可以深入了解层压板在微观尺度上的破坏模式。在 90 K 时，单向层压板的分层很明显，向试样边缘延伸。在交叉层压板中，中间平面出现了几条大的贯穿裂缝，试样断裂面上出现了几条小的基体裂缝和空洞。此外，在角材层压板中还观察到分层形成的多条裂缝。

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引用次数: 0

Mechanical properties of diamond-type triply periodic minimal surface structures fabricated by photo-curing 3D printing 通过光固化三维打印技术制造的金刚石型三重周期性最小表面结构的力学性能

IF 6.3 2区材料科学 Q1 MATERIALS SCIENCE, COMPOSITES

Composite Structures

Pub Date : 2024-11-07 DOI: 10.1016/j.compstruct.2024.118695

Chengjun Zeng , Junqi Hu , Liwu Liu , Wei Zhao , Xiaozhou Xin , Xuehao Song , Yanju Liu , Jinsong Leng

Triply periodic minimal surface (TPMS) structures have attracted significant attention owing to their smooth surface configuration and parametric modeling properties. In this study, photo-curing 3D printing was employed to generate diamond-type TPMS structures, and micro-CT scanning revealed the presence of internal defects within the 3D printed TPMS structures. Two key design variables were explored: volume fraction and unit cell size. Quasi-static compression experiments were conducted to delve into the compression properties and energy absorption capabilities of the 3D printed TPMS structures. The findings reveal that increasing the volume fraction significantly enhances the compressive modulus, ultimate strength, and energy absorption capacity of TPMS structures. Additionally, increasing the cell size improves compression properties and energy absorption per unit volume. To predict the coupling effect of volume fraction and unit cell size on the compression performance of TPMS structures, a bivariate quadratic regression model was established. In addition, TPMS structures were subjected to load-unload cyclic experiments, shedding light on the evolution patterns of residual strain and hysteresis energy during cyclic loading. It provides insights into the design of reusable and fatigue-resistant diamond-type TPMS structures for various engineering applications.

三周期最小表面（TPMS）结构因其光滑的表面构造和参数建模特性而备受关注。本研究采用光固化三维打印技术生成金刚石型 TPMS 结构，并通过显微 CT 扫描发现三维打印 TPMS 结构内部存在缺陷。研究探讨了两个关键的设计变量：体积分数和单元尺寸。为了深入研究三维打印 TPMS 结构的压缩特性和能量吸收能力，还进行了准静态压缩实验。研究结果表明，增加体积分数可显著提高 TPMS 结构的压缩模量、极限强度和能量吸收能力。此外，增大单元尺寸还能改善单位体积的压缩性能和能量吸收能力。为了预测体积分数和单元尺寸对 TPMS 结构压缩性能的耦合效应，建立了一个二元二次回归模型。此外，还对 TPMS 结构进行了加载-卸载循环实验，揭示了循环加载过程中残余应变和滞后能的演变规律。该研究为各种工程应用中可重复使用且抗疲劳的金刚石型 TPMS 结构的设计提供了启示。

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引用次数: 0

Tomographic modeling and internal structure analysis of engineering textiles: A parametric approach 工程纺织品的断层建模和内部结构分析：参数方法

IF 6.3 2区材料科学 Q1 MATERIALS SCIENCE, COMPOSITES

Composite Structures

Pub Date : 2024-11-06 DOI: 10.1016/j.compstruct.2024.118679

Bin Yang , Cédric Béguin , Philippe Causse , Yuwei Feng , Jihui Wang

Tomographic modeling of textiles is attractive for numerical investigation of composites due to its ability to reveal the internal architecture. However, reliability is notably dependent on geometrical modeling accuracy, which is still challenging. This paper addresses existing issues using a parametric approach that relies on statistical resampling and spatial autocorrelated prediction. The proposed strategy involves three stages: first, an explicit representation of each fiber tow is derived from the segmented images through statistical resampling in the parametric domain, which is subsequently mapped back to the physical domain according to known spatial autocorrelation. It allows depicting tow surfaces with varying levels of detail. Second, the tow trajectory is parameterized and subjected to a smoothing process, thereby identifying the local fiber orientation as its tangent vector. Finally, the normal cross-sections of tows are solved as intersecting implicit planes with a parametric tubular surface thanks to the parametric representation. This allows evaluating the spatial architectural variability in tows with notable waviness. Examinations were performed by contrasting the proposed approach with existing techniques. This new approach demonstrated better consistency with the ground truth while bringing additional benefits to the geometry reconstruction.

纺织品的层析成像建模能够揭示内部结构，因此对复合材料的数值研究很有吸引力。然而，其可靠性主要取决于几何建模的准确性，而这仍然具有挑战性。本文采用一种依赖于统计重采样和空间自相关预测的参数方法来解决现有问题。所提出的策略包括三个阶段：首先，通过参数域中的统计重采样，从分割图像中得出每个纤维束的明确表示，然后根据已知的空间自相关性将其映射回物理域。这样就能以不同的详细程度描绘纤维束表面。其次，对纤维束轨迹进行参数化和平滑处理，从而将局部纤维方向识别为其切线向量。最后，由于采用了参数化表示方法，纤维束的法线横截面可以作为与参数化管状表面相交的隐含平面来求解。这样就可以评估具有明显波纹的纤维束的空间结构变化。通过将提出的方法与现有技术进行对比，进行了检验。这种新方法与地面实况的一致性更好，同时为几何重建带来了额外的好处。

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引用次数: 0

The role of impact energy and silica concentration on dynamic impact and quasi-static puncture resistance of fabrics treated with shear-thickening fluids 冲击能和二氧化硅浓度对剪切增稠液处理织物的动态冲击和准静态抗穿刺性能的作用

IF 6.3 2区材料科学 Q1 MATERIALS SCIENCE, COMPOSITES

Composite Structures

Pub Date : 2024-11-06 DOI: 10.1016/j.compstruct.2024.118689

Abdulhalim Aşkan , Murat Aydın

The primary objective of this study is to reveal the role of shear-thickening fluids on the low-speed impact behavior and quasi-static puncture resistance conditions of impregnated p-aramid fabric. This was achieved by progressively increasing the silica ratio methodically. Rheological experiments indicated that 60% represents a crucial threshold for silica content, over which the rheological performance of fluids markedly improves. The impregnated targets exhibited a substantial increase in both dynamic impact and quasi-static puncture resistance in comparison to the neat fabric. Results from tests using the same amount of impact energy showed that impregnated targets had much better impact resistance (ranging from 30.5% to 119.2%) and better energy absorption (ranging from 22.9% to 61.3%) than the untreated targets. In quasi-static tests, impregnated targets exhibited significantly higher puncture resistance, ranging from 42.3% to 90.46%, compared to the neat fabric. The enhanced performance of impregnated targets was ascribed to the presence of interfiber friction, the thickening mechanism of the fluid, and the hardness of the particles. Compared to the neat fabric, the performance enhancement achieved in dynamic impact tests is greater than that observed in quasistatic tests. The variation in performance was associated with the contact area of the threat with the target. Due to the intense force exerted by the knife tip, its contact area with the target is smaller in comparison to that of the impactor. This caused the particle hardness and thickening mechanism to play a lesser role in quasi-static tests compared to impact tests. In addition, to reveal the effect of impact energy, tests were carried out at three different impact energy levels: 20J, 40J, and 60J. The impact resistance of both neat and impregnated textiles improved as the impact energy went up. Nevertheless, the neat fabric exhibited a greater augmentation in resistance in contrast to the impregnated one.

本研究的主要目的是揭示剪切增稠流体对浸渍对位芳纶织物的低速冲击行为和准静态抗穿刺条件的影响。这是通过逐步提高二氧化硅的比例来实现的。流变学实验表明，60% 是二氧化硅含量的一个关键临界值，超过这个临界值，流体的流变性能就会明显改善。与纯织物相比，浸渍靶材的动态抗冲击性和准静态抗穿刺性都有大幅提高。使用相同冲击能量进行的测试结果表明，浸渍靶材的抗冲击性能（从 30.5% 到 119.2% 不等）和能量吸收性能（从 22.9% 到 61.3% 不等）均大大优于未处理的靶材。在准静态测试中，浸渍靶材的抗穿刺性能明显高于未处理的织物，从 42.3% 到 90.46%。浸渍靶材性能的提高归因于纤维间摩擦的存在、流体的增稠机制以及颗粒的硬度。与纯织物相比，在动态冲击试验中获得的性能提升大于在准静态试验中观察到的性能提升。性能的变化与威胁与目标的接触面积有关。由于刀尖施加了强大的力，与撞击器相比，刀尖与目标的接触面积较小。这导致准静态试验中颗粒硬度和增厚机制的作用小于冲击试验。此外，为了揭示冲击能量的影响，还在 20J、40J 和 60J 三种不同的冲击能量水平下进行了试验。随着冲击能量的增加，纯纺织品和浸渍纺织品的抗冲击性都有所提高。不过，与浸渍织物相比，纯织物的抗冲击性增强得更多。

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引用次数: 0

Reliability-based multi-objective optimization design of composite patch repair structure using artificial neural networks 利用人工神经网络对复合材料修补结构进行基于可靠性的多目标优化设计

IF 6.3 2区材料科学 Q1 MATERIALS SCIENCE, COMPOSITES

Composite Structures

Pub Date : 2024-11-05 DOI: 10.1016/j.compstruct.2024.118692

Yubo Zhao , Shanyong Xuan , Yuan Wang , Yongbin Li , Xuefeng Yao

Due to the parameter differences and the existence of random factors, the performance of composite repair structure shows a large dispersion. In order to obtain stronger, lighter and more reliable repair structure, multi-objective optimization design of carbon fiber reinforced polymers (CFRP) laminate repair structure is investigated by combining the reliability theory, artificial neural networks and the genetic algorithm. First, a 3D simulation model of the composite laminate patch repair structures is established using the 3D Hashin criterion and the cohesive region model. Then, the Latin Hypercube sampling (LHS) method is used to realize the random sampling, and the strength proxy model of the repair structure is established by using Back-propagation artificial neural network, further a multi-objective optimization model with tensile strength, reliability and weight as objective functions is built considering the design parameters and the random parameters. Finally, NSGAⅡalgorithm is used to solve the multi-objective optimization problem, and a set of solutions on the Pareto front surface are obtained, also the optimal design parameters of the composite repair structure meets the requirements is obtained.

由于参数差异和随机因素的存在，复合材料修复结构的性能表现出较大的离散性。为了获得更强、更轻、更可靠的修复结构，结合可靠性理论、人工神经网络和遗传算法，研究了碳纤维增强聚合物（CFRP）层状修复结构的多目标优化设计。首先，利用三维哈欣准则和内聚区域模型建立了复合材料层压板修补结构的三维仿真模型。然后，利用拉丁超立方采样（LHS）方法实现随机抽样，并利用反向传播人工神经网络建立修复结构的强度代理模型，进一步考虑设计参数和随机参数，建立以抗拉强度、可靠性和重量为目标函数的多目标优化模型。最后，利用 NSGAⅡ算法求解多目标优化问题，得到帕累托前沿面上的一组解，并得到复合材料修复结构的最优设计参数。

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引用次数: 0

A multi-linear constitutive relation considering the temperature effect on quasi-static mode I delamination in UD/MD laminates 考虑温度对 UD/MD 层板准静态 I 模式分层影响的多线性组合关系

IF 6.3 2区材料科学 Q1 MATERIALS SCIENCE, COMPOSITES

Composite Structures

Pub Date : 2024-11-05 DOI: 10.1016/j.compstruct.2024.118691

Luohuan Zou , Yu Gong , Dingli Tian , Yuting Gao , Jianyu Zhang , Libin Zhao , Ning Hu

In this study, a multi-linear constitutive relation taking into account temperature and fiber bridging is proposed for characterizing delamination behavior in composite laminates under various temperature conditions. An approach combining analytical solution and J-integral is also established for determining the cohesive parameters in the multi-linear constitutive relation. To validate the proposed constitutive relation, mode I quasi-static delamination experiments of unidirectional (UD) and multidirectional (MD) carbon/bismaleimide laminates are carried out at 25 ℃ (room temperature), 80 °C and 130 ℃. The experimental results show that the increasing temperature resulted in a monotonic increase in the fracture toughness of the UD laminates while affect the fracture toughness of MD laminates slightly. A FE model is established with the implementation of the proposed multi-linear constitutive relation using UMAT subroutine. Good agreements between the experimental and simulated results demonstrate the validity of the proposed constitutive relation, with the relative difference of peak load between predicted and experimental values less than 8.2 % and the relative difference of initial and steady-state fracture toughness between predicted and tested results less than 15 %. This study provides the possibility to numerically study the temperature effect on the delamination behavior of laminates and has promising applications in the damage tolerance design of composite structures.

本研究提出了一种考虑温度和纤维桥接的多线性构成关系，用于描述各种温度条件下复合材料层压板的分层行为。此外，还建立了一种结合分析求解和 J 积分的方法，用于确定多线性构成关系中的内聚参数。为了验证所提出的构成关系，在 25 ℃（室温）、80 ℃ 和 130 ℃ 下对单向（UD）和多向（MD）碳/双马来酰亚胺层压板进行了模式 I 准静态分层实验。实验结果表明，温度升高导致 UD 层压板的断裂韧性单调上升，而对 MD 层压板的断裂韧性影响较小。通过使用 UMAT 子程序实现所提出的多线性构成关系，建立了一个有限元模型。实验结果和模拟结果之间的良好一致性证明了所提出的构成关系的有效性，预测值和实验值之间的峰值载荷相对差异小于 8.2%，预测值和测试结果之间的初始和稳态断裂韧性相对差异小于 15%。这项研究为数值研究温度对层压板分层行为的影响提供了可能，在复合材料结构的损伤容限设计中具有广阔的应用前景。

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引用次数: 0

Hybrid composite-metal structure response to post-impact compression – Experimental and numerical study 混合复合金属结构对冲击后压缩的响应--实验和数值研究

IF 6.3 2区材料科学 Q1 MATERIALS SCIENCE, COMPOSITES

Composite Structures

Pub Date : 2024-11-02 DOI: 10.1016/j.compstruct.2024.118685

Piotr Podolak, Patryk Jakubczak, Jarosław Bieniaś

Numerical analysis of the post-impact damage propagation process during CAI tests on titanium-based fibre metal laminates was conducted, and the model was validated by collation of mechanical parameters predicted by it with experimental results. Delaminations induced by the impact were claimed as the hotspot for other modes propagation in most of studied cases and intensively propagated shortly before reaching peak compressive force. Metal – composite interfaces away from impact surface were locations of most intensive delamination propagation during CAI, constituting 63.5 % of overall damage area for titanium-carbon laminate and 81.6 % for titanium-glass laminate. Similarly to delaminations, damage due to fibre and matrix compression propagated from impact point and lead to significant load-carrying ability loss even in low volumes. Propagation of fibre and matrix tension was connected more to buckling progression, than post-impact damage and had the highest volumetric share in composite layers damage modes (max 13.5 % for titanium-carbon laminate and 8.3 % for titanium-glass laminate).

对钛基纤维金属层压板进行 CAI 试验期间的冲击后损伤扩展过程进行了数值分析，并通过将其预测的机械参数与实验结果进行核对验证了该模型。在大多数研究案例中，冲击引起的分层被认为是其他模式传播的热点，并在达到峰值压缩力前不久集中传播。在 CAI 期间，远离撞击表面的金属-复合材料界面是分层传播最密集的位置，占钛-碳层压板总损伤面积的 63.5%，占钛-玻璃层压板总损伤面积的 81.6%。与分层类似，纤维和基体压缩造成的损坏也从撞击点开始扩展，即使在低体积情况下也会导致承载能力的显著下降。纤维和基体张力的传播与屈曲进展的关系比冲击后损伤更大，在复合材料层损伤模式中所占的体积比例也最高（钛-碳复合材料的最大比例为 13.5%，钛-玻璃复合材料的最大比例为 8.3%）。

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引用次数: 0

A rotating triangular auxetic perforated plate: Structural design and characteristic analysis 旋转三角形辅助穿孔板：结构设计和特性分析

IF 6.3 2区材料科学 Q1 MATERIALS SCIENCE, COMPOSITES

Composite Structures

Pub Date : 2024-11-02 DOI: 10.1016/j.compstruct.2024.118684

Tao Xue, Wei Zhong Jiang, Yi Zhang, Nian Ci Du, Jun Wen Shi, Yi Chao Qu, Xin Ren

Auxetic metamaterials have garnered extensive attention over the past few decades due to their exceptional and superior mechanical properties. However, owing to their unique porous structure, it is challenging to ensure that structures possess strong energy absorption capabilities while exhibiting excellent auxetic characteristics. This study introduces a rotating triangular auxetic metamaterial (RTAM) by perforating traditional rigid rotating triangles. Quasi-static compression tests and numerical simulations are conducted on the new structure to investigate the effects of wall thickness and re-entrant angle of the triangular perforated plate on mechanical properties and Poisson’s ratio. The plateau stress and specific energy absorption (SEA) of RTAM are 4 and 10 times higher than that of traditional trichiral auxetic metamaterials (TCAM), respectively. With an increase in wall thickness, both plateau stress and SEA of the structure are improved significantly. As the re-entrant angle increases, the SEA of the structure initially decreases and then increases. RTAM achieves both lightweight structure and ideal mechanical performance, providing an approach for manufacturing lightweight and high-strength auxetic metamaterials, with significant potential applications in the field of energy absorption.

在过去的几十年里，助磁超材料因其卓越的机械性能而受到广泛关注。然而，由于其独特的多孔结构，要确保其结构在表现出优异的辅助特性的同时还具有强大的能量吸收能力是一项挑战。本研究通过在传统的刚性旋转三角形上穿孔，引入了旋转三角形辅助超材料（RTAM）。通过对新结构进行准静态压缩试验和数值模拟，研究了穿孔三角形板的壁厚和重入角对力学性能和泊松比的影响。RTAM 的高原应力和比能量吸收（SEA）分别是传统三螺旋辅助超材料（TCAM）的 4 倍和 10 倍。随着壁厚的增加，结构的高原应力和比能量吸收都有显著改善。随着再入角的增大，结构的 SEA 先减小后增大。RTAM 实现了轻质结构和理想的机械性能，为制造轻质高强度的辅助超材料提供了一种方法，在能量吸收领域具有巨大的应用潜力。

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引用次数: 0

Extension of the crack equivalent method applied to mode II fracture of thermoplastic composites bonded joints using the ENF test 利用 ENF 试验扩展应用于热塑性复合材料粘接接头模式 II 断裂的裂缝等效方法

IF 6.3 2区材料科学 Q1 MATERIALS SCIENCE, COMPOSITES

Composite Structures

Pub Date : 2024-11-02 DOI: 10.1016/j.compstruct.2024.118687

J.P. Reis , M.F.S.F. de Moura , R.D.F. Moreira

Thermoplastic based composites (TPC) have emerged as a new generation of eco-friendly materials with tougher matrices capable of overcoming the major weaknesses of the thermoset counterparts related with poor resistance to delamination and recycling difficulties. Although TPC materials present low surface energy, adhesive bonding is still effective when the requirements for fusion bonding procedures are not met. Recent advances in adhesive technology have unveiled two-part acrylic adhesive specifically designed for low energy surfaces, characteristic of TPC materials. In this work, unidirectional carbon-reinforced polyamide 6 (CF/PA6) bonded joint was characterized under pure mode II loading using end-notched flexure (ENF) test. The experimental fracture tests revealed unstable crack propagation and a data reduction scheme based on the equivalent crack concept was developed to obtain the strain energy release rate distribution along the crack front for the specimen’s length beyond the actuator central loading point. The proposed procedure was successfully validated using a finite element analysis including a cohesive zone modelling and applied to the experimental results. The obtained Resistance-curves showed that this adhesive is capable to provide a significant bonding resistance in pure mode II loading even in low energy surfaces characteristic of TPC materials.

热塑性复合材料（TPC）是新一代的环保材料，其基体更加坚韧，能够克服热固性材料的主要弱点，即抗分层能力差和回收困难。虽然 TPC 材料的表面能较低，但在不符合熔融粘合程序要求的情况下，粘合剂粘合仍然有效。粘合剂技术的最新进展揭示了双组分丙烯酸粘合剂专为 TPC 材料所特有的低能表面而设计。在这项工作中，采用端部缺口挠曲（ENF）试验对单向碳增强聚酰胺 6（CF/PA6）粘接接头在纯模式 II 负载下的性能进行了表征。实验性断裂测试显示了不稳定的裂纹扩展，基于等效裂纹概念开发了一种数据还原方案，以获得沿裂纹前沿试样长度超出致动器中心加载点的应变能释放率分布。利用包括内聚区建模在内的有限元分析成功验证了所提出的程序，并将其应用于实验结果。所获得的阻力曲线表明，即使在 TPC 材料特有的低能量表面，这种粘合剂也能在纯模式 II 加载中提供显著的粘合阻力。

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引用次数: 0