今日更新:Composite Structures 3 篇,Composites Part A: Applied Science and Manufacturing 2 篇,Composites Part B: Engineering 2 篇,Composites Science and Technology 1 篇
Rapid identification of fatigue degradation law of composite material based on IR thermography
Yan Yan, Marie-Laetitia Pastor, Emmanuelle Abisset-Chavanne, Xiaojing Gong
doi:10.1016/j.compstruct.2024.118787
基于红外热像仪的复合材料疲劳退化规律快速识别
The stiffness degradation law is a key part of the simulation model to predict the fatigue behaviors of CFRPs. Traditional approaches to determine this law are time-consuming while with infrared radiation (IR) thermography, the stiffness degradation can be characterized by applying a rapid fatigue test, which takes a fairly short period. However, the stiffness degradation measured during rapid fatigue tests by thermography is under multiple stress levels and limited cycles. In this work, a stiffness degradation law determined by classic fatigue test, originally proposed for unidirectional CFRP laminates, has been extended to multi-directional laminates. Then, a strategy to establish the normalized stiffness degradation law has been developed based on rapid fatigue tests by thermography. The non-linear cumulative damage rule has been considered to analyze the damage condition at the beginning of each stress level during rapid fatigue test by thermography. Thus, the test time can be greatly reduced for the determination of this law which is necessary for the prediction of the fatigue life by numerical simulation. The numerical results of the fatigue life prediction for two kinds of multi-directional laminates using stiffness degradation law based on thermographic measurement correlate very well with those obtained from the measurements during classic fatigue tests.
刚度退化规律是碳纤维复合材料疲劳性能预测模型的关键部分。传统的方法来确定这一规律是耗时的,而使用红外辐射(IR)热像仪,刚度退化可以通过应用快速疲劳试验来表征,这需要相当短的时间。然而,在快速疲劳试验中,热成像测量的刚度退化是在多个应力水平和有限循环下进行的。本文将原先针对CFRP单向板提出的经典疲劳试验确定的刚度退化规律推广到多向板。在此基础上,提出了一种基于热成像快速疲劳试验的归一化刚度退化规律建立策略。考虑非线性累积损伤规律,利用热像仪分析快速疲劳试验中各应力水平开始时的损伤情况。这一规律的确定大大缩短了试验时间,为数值模拟预测疲劳寿命提供了必要条件。采用基于热像仪测量的刚度退化规律对两种多向层合板进行疲劳寿命预测的数值结果与经典疲劳试验结果吻合较好。
Computational and experimental studies on lapped bistable composite booms
Chenchen Wu, Jiawei Fan, Kunpeng Guan, Zhongliang Chang, Pengyuan Zhao, Shuai Yue, Liang Li, Dingguo Zhang
doi:10.1016/j.compstruct.2024.118795
搭接双稳复合臂架的计算与实验研究
Lightweight plain-woven fabrics with improved inter-laminar shear properties are suitable candidates for manufacturing bistable reeled composite (BRC) booms that require multiple ultra-thin layers. BRCs are typically constructed with antisymmetrical laminate stacking sequences with certain fibre orientation angles, which introduce laps during the production of extremely long BRCs with plain-woven fabrics. This paper focuses on computational and experimental analyses of lapped plain-woven BRCs during snap through and coiling up. The effects of lap joints on the bistability and damage during snap-through and coiling-up processes for antisymmetrically laminated carbon/epoxy plain-woven BRCs with and without lap joints were investigated. The results indicate that a larger driving force is required for lapped BRCs than for those without lap joints to reach the critical load during snap through, and this requirement increases with increasing lap length. To investigate the damage behaviours of the BRCs during the coiling-up process, strain-gauge measurements and scanning electron microscopy (SEM) tests of the damaged area were conducted. The results show that tensile fracture of the resin is the primary failure mode during equal-sense coiling up, whereas both tensile fracture of the resin and fibre damage occur during opposite-sense coiling up.
具有改进的层间剪切性能的轻质平纹织物是制造需要多个超薄层的双稳态卷绕复合材料(BRC)臂架的合适候选材料。brc通常由具有一定纤维取向角的不对称层压堆叠序列构成,这在用平纹织物生产超长brc时引入了搭接。本文主要对搭接平纹织物BRCs的搭接贯通和卷取过程进行了计算和实验分析。研究了搭接对带搭接和不带搭接的不对称复合碳/环氧平纹编织BRCs的双稳性以及搭接和卷取过程中损伤的影响。结果表明,与未搭接的BRCs相比,搭接BRCs在搭接过程中需要更大的驱动力才能达到临界载荷,并且这一要求随着搭接长度的增加而增加。为了研究BRCs在卷取过程中的损伤行为,对损伤区域进行了应变测量和扫描电子显微镜(SEM)测试。结果表明,等感卷取过程中树脂的拉伸断裂是主要的破坏模式,相反感卷取过程中树脂的拉伸断裂和纤维的拉伸损伤同时发生。
Numerical analysis of particle reinforced composites with interphases by three-dimensional thermal-elasto-plastic Voronoi cell finite element method
Jiangbo Tao, Rui Zhang, Ran Guo
doi:10.1016/j.compstruct.2024.118774
含界面相颗粒增强复合材料三维热弹塑性Voronoi单元有限元数值分析
Research results on linear elasticity problems by the three-dimensional Voronoi cell finite element method (VCFEM) are available. This paper presents a three-dimensional thermo-elasto-plastic VCFEM for analyzing the nonlinear mechanical behavior of particle-reinforced composites containing interphase. The model includes a matrix phase, interphase phase, and inclusion phase, and the three phases satisfy the continuity condition of traction. This paper derives an incrementally modified complementary function and constructs a higher order stress function considering the ellipsoidal interface, which is used in the iterative analysis of the plasticity and thermal problems of three-dimensional Voronoi cells with interphase. Compared with the displacement finite element method, the comparison result pointed out that VCFEM has the advantages of simple mesh generation and fast speed under the same accuracy.
利用三维Voronoi单元法(VCFEM)对线弹性问题进行了研究。提出了一种三维热弹塑性VCFEM方法,用于分析含界面相颗粒增强复合材料的非线性力学行为。该模型包括基体相、间相和夹杂相,三者均满足牵引的连续性条件。本文推导了考虑椭球面界面的增量修正互补函数,构造了高阶应力函数,用于具有界面的三维Voronoi细胞的塑性和热问题的迭代分析。与位移有限元法进行对比,结果表明,在相同精度下,VCFEM具有网格生成简单、速度快的优点。
Chemical bridging of ammonium octamolybdate and silica for highly efficient smoke suppression of polyvinyl chloride-based composites
Ting-Ting Suo, Ze-Yong Zhao, Yu-Zhong Wang, Cong Deng
doi:10.1016/j.compositesa.2024.108650
八胺酸铵与二氧化硅的化学桥接用于聚氯乙烯基复合材料的高效抑烟
Smoke hazard is the most dangerous in a fire accident. Cheap inorganic materials such as silica may promote the smoke suppression property of polymer-based composites, but show low efficiency because of chemical inertia in burning scenario. In this work, ammonium octamolybdate (AOM) was chemically incorporated into hydrophobic nano silica (SiO2) with a silane coupling agent as a bridge, and the resulting MSiO2-AOM displayed significantly improved smoke suppression compared with the mixture of SiO2 and AOM. While applying typical polyvinyl chloride wood-plastic building composite (WPC), total smoke production (TSP) and the maximum smoke density (Dsmax) were respectively decreased by 37% and 42% at only 20 phr MSiO2-AOM (5.0 wt%). Herein, the essential reasons for the effect of MSiO2-AOM on overall performance of WPC were also discussed in detail. This work provides an effective method to upgrade the traditional SiO2 to efficient smoke suppressant by a simple bridging effect.
火灾事故中最危险的是烟雾。廉价的无机材料如二氧化硅可以提高聚合物基复合材料的抑烟性能,但由于燃烧时的化学惯性,其抑烟效率较低。本文以硅烷偶联剂为桥接剂,将八胺钼酸铵(AOM)化学掺入疏水性纳米二氧化硅(SiO2)中,得到的八胺钼酸铵(MSiO2-AOM)的抑烟性能明显优于二氧化硅-八胺钼(AOM)的混合物。当使用典型聚氯乙烯木塑建筑复合材料(WPC)时,总产烟量(TSP)和最大烟密度(Dsmax)分别降低37%和42% (MSiO2-AOM为5.0 wt%)。本文还详细讨论了MSiO2-AOM对木复合材料综合性能影响的根本原因。本研究为通过简单的桥接效应将传统SiO2提升为高效抑烟剂提供了一种有效方法。
Study on the parameters optimization of 3D printing continuous carbon fiber-reinforced composites based on CNN and NSGA-II
Jiale Yi, Ben Deng, Fangyu Peng, Aodi Yan, Zhijie Li, Jinguo Shen, Rong Yan, Xiaopeng Xie
doi:10.1016/j.compositesa.2024.108657
基于CNN和NSGA-II的3D打印连续碳纤维增强复合材料参数优化研究
In 3D printing of critical structural components made from continuous carbon fiber-reinforced composites (CCFRC), mechanical performance and manufacturing efficiency are mutually constrained. This paper introduces a novel closed-loop iterative optimization method that swiftly identifies the optimal balance between performance and efficiency for the best overall results. It combines the forecasting capability of Convolutional Neural Networks (CNN) with the optimization strength of Non-dominated Sorting Genetic Algorithm II (NSGA-II). The study found that the optimal parameters as a layup angle of 0°, nozzle temperature of 260 °C, fiber filling density of 80 %, layer thickness of 0.6 mm, and fiber printing speed of 10 mm/s. The results of the optimized process parameters show a 53 % increase in mechanical performance and a 27 % improvement in manufacturing efficiency compared to the sampling experiment results. Therefore, the proposed parameter optimization strategy can quickly determine the optimal process parameters for the given conditions without requiring additional guidance.
在连续碳纤维增强复合材料(CCFRC)关键结构部件的3D打印中,机械性能和制造效率是相互制约的。本文介绍了一种新的闭环迭代优化方法,该方法可以快速识别性能和效率之间的最佳平衡,以获得最佳的总体结果。它结合了卷积神经网络(CNN)的预测能力和非支配排序遗传算法II (NSGA-II)的优化强度。研究发现,最佳参数为铺层角0°,喷嘴温度260 ℃,纤维填充密度80 %,层厚0.6 mm,纤维打印速度10 mm/s。优化后的工艺参数与抽样实验结果相比,机械性能提高了53 %,制造效率提高了27 %。因此,所提出的参数优化策略可以在不需要额外指导的情况下快速确定给定条件下的最优工艺参数。
Composite Scaffolds Based on Egg Membrane and Eggshell-derived Inorganic Particles Promote Soft and Hard Tissue Repair
Zhengchao Yuan, Siyuan Wu, Liwen Fu, Muhammad Shafiq, Yuqing Liang, Peng Li, Xinyi Wang, Hao Feng, Rashida Hashim, Shuqi Lou, Mohamed EL-Newehy, Meera Moydeen Abdulhameed, Weifen Zhang, Xiumei Mo, Shichao Jiang
doi:10.1016/j.compositesb.2024.112071
基于卵膜和蛋壳无机颗粒的复合支架促进软硬组织修复
It is essential to exploit the eggshell membrane (EM) and eggshell (ES) for biomaterial science as a bioresource technology albeit that they are generally considered as waste products of the egg industry. The EM with Janus structural and compositional properties can be prepared into tissue-engineered constructs. The ES was prepared into the inorganic nanoparticles (NPs) namely PCa with an average diameter of 0.67 μm, which was comprised of various inorganic oxides, such as calcium oxide (CaO), and zinc oxide (ZnO). By harnessing the individual advantages of the EM and PCa, they were fabricated into composite scaffolds by a negative pressure inlay method. The composite scaffolds manifested a fibrous network-like structure manifesting large surface area, good mechanical strength (failure force of EM, ca. 1.68 N), biocompatibility and biodegradability in vitro and in vivo. The EM@Ca3 group enabled efficient hemostasis in the liver trauma injury model (hemostasis time, < 32 s), rapid wound healing (96% at day 14), and bone density similar to the normal bone at week 6 post-implantation. Taken together, our approach of leveraging egg-derived bioresource may be worthy for the future investigations of tissue-engineered constructs and potentially other bio-related disciplines.
尽管蛋壳膜(EM)和蛋壳(ES)通常被认为是鸡蛋工业的废物,但将它们作为一种生物资源技术用于生物材料科学是必不可少的。具有Janus结构和组成特性的EM可以制备成组织工程结构。制备了由氧化钙(CaO)、氧化锌(ZnO)等多种无机氧化物组成的平均直径为0.67 μm的无机纳米粒子PCa。利用EM和PCa各自的优势,采用负压镶嵌法制备了复合支架。复合支架呈纤维网状结构,比表面积大,机械强度好(EM破坏力约1.68 N),体外和体内生物相容性和生物降解性好。EM@Ca3组使肝外伤模型有效止血(止血时间< 32 s),伤口愈合迅速(第14天96%),植入后第6周骨密度与正常骨相近。综上所述,我们利用鸡蛋衍生生物资源的方法可能对未来组织工程构建和潜在的其他生物相关学科的研究有价值。
The Effect of Prepreg Ply Thickness in Carbon Fiber Reinforced Composites on Intralaminar Toughness and Shear Strength in Cryogenic Environments for Liquid Hydrogen Storage Tanks
Eduardo Szpoganicz, Fabian Hübner, Uwe Beier, Matthias Geistbeck, Holger Ruckdäschel
doi:10.1016/j.compositesb.2024.112077
碳纤维增强复合材料预浸料厚度对低温环境下液氢储罐层内韧性和剪切强度的影响
This study investigates the effect of prepreg ply thickness on the intralaminar toughness and shear strength of carbon-fiber reinforced polymer (CFRP) in room temperature and cryogenic environments. A toughened epoxy resin, optimized for ultra-low temperatures, was impregnated with unidirectional carbon-fibers at 45, 70, and 140 g/m2 areal weights. The intralaminar energy release rates in modes I and II, along with the interlaminar shear strength, were evaluated under liquid nitrogen (in-situ) testing conditions to assess the performance of these composites in cryogenics. Optical and scanning electron microscopy correlated fiber-matrix distribution and regularity with failure modes and performance. While GIC decreased from 296 K to 77 K, ILSS was notably higher in cryogenic environments. Both intralaminar toughness and interlaminar strength were improved by thinner plies, especially at 77 K. Thus, highlighting the importance of fiber-matrix uniformity in optimizing delamination and shear properties under cryogenic conditions, where sensitivity to irregularities increases.
研究了常温和低温环境下预浸料厚度对碳纤维增强聚合物(CFRP)层间韧性和剪切强度的影响。在一种针对超低温进行了优化的增韧环氧树脂中,分别以45、70和140 g/m2的面积重量浸渍单向碳纤维。在液氮(原位)测试条件下,评估了I和II模式下的层间能量释放率以及层间剪切强度,以评估这些复合材料在低温下的性能。光学和扫描电子显微镜将纤维基质的分布和规律性与失效模式和性能联系起来。当GIC从296 K下降到77 K时,ILSS在低温环境中显著升高。层间强度和层内韧性均随着层厚的增加而提高,尤其是在77 K时。因此,在对不规则性的敏感性增加的低温条件下,强调纤维基质均匀性在优化分层和剪切性能方面的重要性。
Polytetrafluoroethylene Composites for High-Frequency Microwave Applications: Balancing Thermal Conductivity, Adhesion and Dielectric Properties
Lu He, Pengfei Xu, Yongzheng Zhang, Songgang Chai, Zilong Xie, Zhengli Dou, Ziran Guo, Tianhao Yang, Qiang Fu, Kai Wu
doi:10.1016/j.compscitech.2024.111012
用于高频微波应用的聚四氟乙烯复合材料:平衡导热性、粘附性和介电性能
Polytetrafluoroethylene (PTFE) is widely used as a polymer substrate for high-frequency microwave copper cladding due to its low dielectric loss and high stability. However, its inherently low thermal conductivity requires the use of high-content fillers, which complicates efforts to balance thermal conductivity, adhesion strength, and dielectric loss of the composite materials. Herein, we introduce PTFE composites with a hybrid filler network, where the synergistic alignment and interaction of two-dimensional hexagonal boron nitride (h-BN) and granular β-silicon nitride (Si3N4) forms interconnected pathways in the vertical direction. The spatial arrangement of large-sized h-BN can bridge and shorten the thermal conduction path within the Si3N4 network, forming robust vertical thermal pathways, achieving an out-of-plane thermal conductivity of 1.6 W/m K. Additionally, the complementary properties of h-BN and Si3N4 enhance the overall performance. Si3N4 reduces stress concentration, improving adhesion strength, while h-BN’s wide bandgap and weak polarity help minimize dielectric loss. This combination results in a peeling strength of 1.3 N/mm with copper foil and a remarkably low dielectric loss (<0.0011) at 10 GHz. The ultimate PTFE composite ensures reliable, stable, and secure signal transmission in high-frequency communication devices, making it a highly promising material for the electronics sector.
聚四氟乙烯(PTFE)因其介质损耗低、稳定性高等特点,被广泛用作高频微波铜包覆的聚合物衬底。然而,其固有的低导热性要求使用高含量的填料,这使得平衡复合材料的导热性、粘附强度和介电损耗的努力变得复杂。本文中,我们引入了具有杂化填料网络的PTFE复合材料,其中二维六方氮化硼(h-BN)和颗粒状β-氮化硅(Si3N4)在垂直方向上形成相互连接的路径。大尺寸h-BN的空间布局可以桥接和缩短Si3N4网络内部的热传导路径,形成坚固的垂直热通道,实现1.6 W/m k的面外导热系数。此外,h-BN和Si3N4的互补特性增强了整体性能。Si3N4降低了应力集中,提高了粘附强度,而h-BN的宽带隙和弱极性有助于降低介电损耗。这种组合导致铜箔的剥离强度为1.3 N/mm,并且在10 GHz时具有非常低的介电损耗(<0.0011)。终极聚四氟乙烯复合材料可确保高频通信设备中可靠,稳定和安全的信号传输,使其成为电子行业非常有前途的材料。