今日更新:Composite Structures 4 篇,Composites Part A: Applied Science and Manufacturing 3 篇,Composites Part B: Engineering 1 篇,Composites Science and Technology 1 篇
Towards detailed oxidation depth and weight loss: A computational and kinetic modeling study of Carbon/Carbon composites oxidation
Fan Zhang, Hongjian Zhang, Shuai Liu, Haitao Cui, Zheyuan Lai
doi:10.1016/j.compstruct.2025.119118
走向详细的氧化深度和重量损失:碳/碳复合材料氧化的计算和动力学建模研究
Carbon/Carbon(C/C) composites are increasingly applied in hot-end components of aero-engines due to superior high-temperature mechanical properties. However, C/C composites are susceptible to oxidation under high-temperature conditions, restricting the application of C/C composites. In this research, a three-dimensional diffusion oxidation kinetic model in the diffusion-controlled oxidation stage was established for C/C composites with an anti-oxidation coating based on mass transfer and diffusion theory. Subsequently, the relationship between oxidation amount and crack oxidation propagation depth with oxidation time was calculated. The oxidation damage of C/C composites in the atmosphere at 700 ℃ ∼900 ℃ was evaluated by weight loss analysis and scanning electron microscopy (SEM) experimentally. Compared with the oxidation kinetic model, the measured values of oxidation weight loss and oxidation depth were in good agreement with the prediction of the model with the maximal error of 7.55 % and 10.87 % respectively, verifying the reliability of the model. Additionally, the sensitivity of oxidation depth to oxidation duration, oxygen partial pressure (OPP) and coating thickness at different temperature are analyzed, aiming to provide a model to predict the oxidation degree and provide reliable recommendations for thermal protection and antioxidant design of C/C composites.
碳/碳(C/C)复合材料由于具有优异的高温力学性能,在航空发动机热端部件中得到越来越多的应用。然而,C/C复合材料在高温条件下容易氧化,限制了C/C复合材料的应用。本研究基于传质扩散理论,建立了含抗氧化涂层的C/C复合材料扩散控制氧化阶段的三维扩散氧化动力学模型。随后,计算了氧化量和裂纹氧化扩展深度随氧化时间的关系。通过失重分析和扫描电镜(SEM)实验评价了C/C复合材料在700 ℃~ 900 ℃大气中的氧化损伤。与氧化动力学模型比较,氧化失重和氧化深度的实测值与模型预测吻合较好,最大误差分别为7.55 %和10.87 %,验证了模型的可靠性。分析了不同温度下氧化深度对氧化持续时间、氧分压(OPP)和涂层厚度的敏感性,旨在建立预测氧化程度的模型,为C/C复合材料的热防护和抗氧化设计提供可靠的建议。
Experimental and numerical study on draping behavior of recycled textile composite reinforcement with different weave patterns
Bo Chen, Bowen Xu, Yang Zhang, Xiaoling Liu
doi:10.1016/j.compstruct.2025.119123
不同织型再生纺织复合材料增强材料悬垂性能的实验与数值研究
This study experimentally and numerically analyzes the draping of recycled fabric with different weave patterns. The recycled fabric was obtained from waste prepregs using a designed microwave thermal process. It is shown that the yarn width and density remain unchanged in the recycling process, but the fiber surface properties are changed, including a decrease in diameter and an increase in roughness. Due to the removal of sizing agents and the fiber diameter decrease, the recycling process also leads to a reduction in fabric thickness and areal density by about 9%. This change significantly modified the mechanical behavior of recycled fabrics compared to virgin fabrics, especially the bending stiffness of recycled fabrics is greatly reduced. Hemisphere and square box forming tests indicated that recycled fabrics tend to wrinkle more than virgin fabrics, and fabrics with a loose structure and less crimp lead to good drapability. A stress resultant shell approach gives simulation results that are in agreement with experiments, particularly the onset of wrinkling. This numerical approach takes into account tensile, in-plane shear, bending and friction behavior of textile reinforcement to reflect the change in fiber properties and weave structures, which proved to have a notable influence on fabric drapability.
本文对不同织型再生织物的悬垂性能进行了实验和数值分析。采用设计的微波加热工艺,从废预浸料中获得再生织物。结果表明,在回收过程中,纱线的宽度和密度保持不变,但纤维的表面性能发生变化,包括直径减小和粗糙度增加。由于施胶剂的去除和纤维直径的减小,回收过程还导致织物厚度和面密度减少约9%。这一变化明显改变了再生织物的力学性能,特别是再生织物的抗弯刚度大大降低。半球和方盒成型试验表明,回收织物比原始织物更容易起皱,结构松散、卷曲少的织物具有良好的垂性。应力产生壳方法给出了与实验一致的模拟结果,特别是起皱的开始。该数值方法考虑了织物增强物的拉伸、面内剪切、弯曲和摩擦行为,以反映纤维性能和组织结构的变化,这些变化对织物的垂降性有显著影响。
Investigation of temperature and structural configuration effects on the mechanical properties of CFRP bolted joints
Xiaodong Liu, Kai Huang, Xiaojian Han, Jindi Zhou, Li Zhang, Licheng Guo
doi:10.1016/j.compstruct.2025.119128
温度和结构形式对CFRP螺栓连接力学性能影响的研究
Composite bolted joints are extensively employed in structural applications and have garnered notable interest in composite component design. This research examined how temperature, hole size, and washer configuration influence the composite bolted joint’s tensile properties, using 3D digital image correlation (DIC) and acoustic emission (AE) methods. The study analyzed load–displacement response, surface strain evolution, damage mode characterization, and damage initiation of joint throughout the tensile testing. The strain and displacement fields of the joint surfaces effectively revealed the competing evolution mechanisms between axial tensile effect and secondary bending effect. The k-means++ clustering algorithm and sentry function were employed to accurately identify damage modes and initiation in the joints. The results indicate that temperature, hole diameter, and washer configuration significantly influence joint strength, with the dominance of axial tensile effects and secondary bending effects varying depending on the load level. Double-sided washers delay damage initiation, while an increase in hole diameter causes damage to initiate earlier. High temperatures significantly delay the initiation of various damage modes.
复合材料螺栓连接广泛应用于结构应用,并引起了复合材料构件设计的关注。本研究采用三维数字图像相关(DIC)和声发射(AE)方法,研究了温度、孔尺寸和垫圈配置对复合螺栓连接拉伸性能的影响。在整个拉伸试验过程中,研究分析了节点的载荷-位移响应、表面应变演化、损伤模式表征和损伤起始。接头表面的应变场和位移场有效地揭示了轴向拉伸效应和二次弯曲效应之间的竞争演化机制。采用k-means++聚类算法和哨兵函数准确识别接头损伤模式和起裂。结果表明,温度、孔直径和垫圈配置对接头强度有显著影响,轴向拉伸效应占主导地位,二次弯曲效应随载荷水平而变化。双面垫圈可以延缓损伤的发生,而增大孔径则会使损伤发生得更早。高温显著延缓了各种损伤模式的发生。
Optimization of preloading process combining elastic interaction and creep relaxation for multi-constraint composite structures
Chang Gao, Yujin Lin, Chenxuan Hu, Haidong Yu
doi:10.1016/j.compstruct.2025.119130
多约束复合材料结构弹性相互作用与蠕变松弛相结合的预压过程优化
The preloading process of composite structure constrained by multiple bolted joints is difficult to be controlled because the elastic interaction between bolts and the creep relaxation of multi-layer viscoelastic structures exist simultaneously. In this paper, an optimization method of preload for multi-constraint composite structure is proposed by combining elastic interaction and long-term load relaxation. The composite structure is equivalent to the viscoelastic multi-layer structure and the load caused by creep relaxation for the multiple bolts is derived based on the viscoelastic constitutive model. The elastic interaction of bolts in relaxation process is considered and the interactive stiffness of multiple bolts is constructed. The iterative algorithm for the preload coupled with creep relaxation and elastic interaction is established. The attenuation behavior of the preload with different initial preloads and sequences for multi-constraint composite structure can be predicted. A data-driven surrogate model for the prediction of preload evolution is established, by which the variation of preload with different preloading processes can be calculated rapidly. Then, the magnitude and uniformity of preload are taken as the optimized objective and the optimal initial preloading parameters are solved, which is useful for the manufacturing of multi-constraint composite structures with long-term storage.
由于螺栓之间的弹性相互作用和多层粘弹性结构的蠕变松弛同时存在,复合结构在多个螺栓连接约束下的预压过程难以控制。本文提出了一种结合弹性相互作用和长期载荷松弛的多约束复合材料结构预紧力优化方法。将复合结构等效为粘弹性多层结构,并基于粘弹性本构模型推导了多螺栓蠕变松弛引起的荷载。考虑锚杆松弛过程中的弹性相互作用,构造了多锚杆的相互作用刚度。建立了考虑蠕变松弛和弹性相互作用的预紧力迭代算法。可以预测多约束复合材料结构在不同初始预紧力和预紧力顺序下的预紧力衰减行为。建立了数据驱动的预紧力演化预测代理模型,可快速计算预紧力随不同预紧过程的变化。然后,以预紧力的大小和均匀性为优化目标,求解了最优初始预紧力参数,为制造具有长期存储能力的多约束复合材料结构提供了理论依据。
Stochastic multi-scale modeling for estimating the Mode-I dynamic fracture toughness of CNT-reinforced polymers
Reza Yazdanparast, Roham Rafiee
doi:10.1016/j.compositesa.2025.108882
估计碳纳米管增强聚合物i型动态断裂韧性的随机多尺度模型
A stochastic hierarchical multiscale model is developed to estimate the Mode-I dynamic fracture toughness of CNT-reinforced polymers, capturing both processing-induced inconsistencies and strain rate effects. At the nanoscale, molecular dynamic simulations of CNT pull-out from the matrix are performed to analyze the CNT-polymer interfacial properties at various pull-out speeds. At the microscale, a rate-dependent finite element model is established to characterize the pull-out profiles for different CNT lengths, orientations, and waviness at various pull-out speeds. Then, the CNT bridging phenomenon along the crack growth path is modeled considering viscoelastic-viscoplastic behavior for the matrix. The influence of CNT lengths, waviness patterns, orientations, and volume fractions at the microscale, as well as CNT agglomeration effects at the mesoscale, on critical fracture energy (GID) are determined. At the macroscale, stochastic simulation is performed to estimate GID treating involved uncertainties as random variables. Predicted results are in very good agreement with experimental observations.
建立了一个随机分层多尺度模型来估计碳纳米管增强聚合物的i型动态断裂韧性,同时捕获了加工引起的不一致性和应变率效应。在纳米尺度上,进行了碳纳米管从基体中拔出的分子动力学模拟,分析了碳纳米管聚合物在不同拔出速度下的界面特性。在微观尺度上,建立了一个速率相关的有限元模型来表征不同碳纳米管长度、方向和波浪度在不同拉出速度下的拉出曲线。然后,考虑基体的粘弹-粘塑性行为,建立了碳纳米管沿裂纹扩展路径的桥接现象模型。研究了碳纳米管的长度、波浪形状、取向和体积分数在微观尺度上以及碳纳米管在中尺度上的团聚效应对临界断裂能(GID)的影响。在宏观尺度上,将涉及的不确定性作为随机变量,进行随机模拟来估计GID。预测结果与实验结果非常吻合。
Biaxial bending failure behavior of laminated composite plates under ring-on-ring loading: Effect of layups and interactive terms in failure criteria
Junru Li, Weiyi Kong, Weijie Zhang, Yiding Li, Xuan Zhang, Shibo Yan
doi:10.1016/j.compositesa.2025.108883
环对环加载下层合复合材料板的双轴弯曲破坏行为:层合层的影响和破坏准则中的交互项
This study investigates the biaxial bending failure behavior of laminated composites, through ring-on-ring loading as described by the ASTM C1499 standard, originally developed for isotropic materials. Cross-ply and quasi-isotropic layups of two thicknesses were tested to assess failure mechanism under layup effect. Thin plates exhibited pronounced nonlinear stiffness across different layups while differences diminished in thick laminates. A numerical model employing the recently formulated Fully Rationalized Tsai-Wu failure criterion and further extending the criterion to identify failure modes to facilitate property degradation is developed for failure prediction under multiaxial stress states, aligning well with experimental results without requiring fitting model parameters. The inclusion of interactive terms in the criterion successfully captured multiaxial failure compared to non-interactive ones. Further stress analysis indicates the ASTM C1499 standard is not entirely applicable to laminates regarding equibiaxial flexural strength but highlights its potential for biaxial tensile testing of unidirectional laminates under non-equal stress ratios.
本研究通过ASTM C1499标准所描述的环对环加载来研究层合复合材料的双向弯曲破坏行为,该标准最初是为各向同性材料开发的。对两种厚度的交叉铺层和准各向同性铺层进行了试验,以评估铺层效应下的破坏机制。薄板表现出明显的非线性刚度跨越不同的层压板,而差异减少在厚层压板。采用新近提出的完全合理化的Tsai-Wu破坏准则,并进一步扩展该准则以识别破坏模式以促进性能退化,建立了多轴应力状态下的破坏预测的数值模型,该模型无需拟合模型参数即可与实验结果很好地吻合。与非交互项相比,在准则中包含交互项成功地捕获了多轴破坏。进一步的应力分析表明,ASTM C1499标准并不完全适用于层压板的等双轴弯曲强度,但强调了其在非等应力比下单向层压板的双轴拉伸测试的潜力。
Orthotropic elastic constants and tensile strength of extrusion-based additively manufactured Carbon/Carbon composites after polymer infiltration and pyrolysis
Edwin S. Romero, Bryant Burton, Ashley Hilmas, Eduardo Barocio, Rodney W. Trice
doi:10.1016/j.compositesa.2025.108884
聚合物浸润和热解后增材制造碳/碳复合材料的正交各向异性弹性常数和拉伸强度
This study was aimed at obtaining orthotropic elastic constants and tensile strengths of extrusion-based additively manufactured (EDAM) carbon/carbon (C/C) composites. Micro-computed tomography (µCT) data was coupled with impulse excitation data and Mori-Tanaka homogenization- based microstructural modeling to analyze 50 wt% short carbon fiber-loaded polyphenylene sulfide (PPS)-based C/C composites. After five polymer infiltration and pyrolysis cycles, the elastic constants and average tensile strength were found to be E1 = 30.48 GPa, E2 = 17.85 GPa, E3 = 12.34 GPa, G23 = 5.57 GPa, G13 = 6.65 GPa, G12 = 9.19 GPa, ν23 = 0.28, ν13 = 0.25, ν12 = 0.26, and σT = 12.71 MPa, respectively. The results were unique to the fiber orientation induced during 3D printing and pore volume fraction achieved with densification and highlights the Mori-Tanaka- based microstructural modeling as a beneficial tool for capturing the fiber architecture- and process- dependent behavior of C/C composites.
研究了挤压增材制造(EDAM)碳/碳(C/C)复合材料的正交异性弹性常数和拉伸强度。微计算机断层扫描(µCT)数据与脉冲激励数据和基于Mori-Tanaka均质化的微观结构建模相结合,分析了50 wt%短碳纤维负载聚苯硫醚(PPS)基C/C复合材料。5聚合物渗透和裂解周期后,弹性常数和平均抗拉强度被发现E1 = 30.48的绩点,E2 = 17.85的绩点,E3 = 12.34的绩点,G23 = 5.57的绩点,G13 = 6.65的绩点,G12 = 9.19的绩点,ν23 = 0.28,ν13 = 0.25,ν12 = 0.26,分别和σT = 12.71 MPa。该结果是3D打印过程中诱导的纤维取向和致密化过程中获得的孔隙体积分数的独特结果,并突出了基于Mori-Tanaka的微结构建模是捕获纤维结构和工艺相关行为的有益工具。
Enhanced tensile properties of 3D printed soft-hard composites due to Poisson’s ratio mismatch: Experimental and numerical study
Peijie Sun, Weizhu Yang, Yu Zhang, Baiyu Zhang, Zheming Fan, Lei Li
doi:10.1016/j.compositesb.2025.112413
泊松比失配对3D打印软硬复合材料拉伸性能的影响:实验与数值研究
A novel design of soft-hard integrated composite is proposed by embedding hard lattices with controllable Poisson’s ratio (PR) at large deformation into the soft matrix. Extensive numerical simulations of the hard lattices with controllable PR (HLCPR) and the designed hard lattice reinforced soft matrix (HLRSM) are conducted based on constitutive parameters of the soft and hard materials obtained from standard material tests. PolyJet 3D printing technique is employed to fabricate the studied HLCPR and HLRSM samples with lattice of PR from -0.8 to 0.8, and tensile tests were conducted with the help of DIC method to obtain their mechanical properties and capture the fracture behaviors. Numerical results agree well with the test results in terms of effective Young’s modulus, strength and fracture behaviors. Results show that coupling between the soft matrix and the HLCPR due to deformation mismatch leads to significant enhancement of mechanical properties, and such coupling effect varies with the PR of the HLCPR. The HLCPR of PR -0.8 leads to the strongest coupling effect, while that of PR 0.4 exhibits the weakest. The soft matrix delays fracture initiation in the HLCPR and transforms the fracture mode from sudden rupture to a progressive failure. Results also demonstrate that HLRSM with HLCPR of -0.8 exhibits superior performance compared to that with an uncontrollable PR or breaking hard lattices. A theoretical model was also carried out to further interpret the deformation mismatch induced coupling effect. This study offers helpful guidance for developing high-performance composite materials and structures.
提出了一种将大变形时泊松比可控的硬晶格嵌入软基体的新型软硬集成复合材料设计方法。基于标准材料试验获得的软硬材料本构参数,对具有可控PR的硬晶格(HLCPR)和设计的硬晶格增强软基体(HLRSM)进行了广泛的数值模拟。采用PolyJet 3D打印技术制备了PR为-0.8 ~ 0.8晶格的HLCPR和HLRSM样品,并利用DIC方法进行拉伸试验,获得了其力学性能和断裂行为。数值计算结果与试验结果在有效杨氏模量、强度和断裂行为等方面吻合较好。结果表明:软基体与HLCPR由于变形失配而产生的耦合作用显著增强了HLCPR的力学性能,且这种耦合效应随HLCPR的PR而变化。PR -0.8的HLCPR耦合效果最强,PR 0.4的HLCPR耦合效果最弱。软基质延缓了HLCPR中断裂的发生,将断裂模式从突然断裂转变为渐进式断裂。结果还表明,当HLCPR为-0.8时,HLRSM的性能优于不可控PR或破硬晶格的HLRSM。建立了理论模型,进一步解释了变形失配引起的耦合效应。该研究为高性能复合材料和结构的开发提供了有益的指导。
Multiscale enhancements in Z-pin reinforcement performance through curing parameters
Jisiyuan Cheng, Yingjie Xu, Weihong Zhang, Weiwei Liu
doi:10.1016/j.compscitech.2025.111157
固化参数对z针增强性能的多尺度影响
Z-pinning is employed by composite laminates to enhance interlaminar performances. Z-pinned composites are then cured to obtain a vastly enhanced interlaminar fracture toughness. However, rare research has focused on the curing effects on the mechanical performances of Z-pinned laminates. This paper presents a multiscale experimental and simulation investigation of the curing effects on the individual Z-pin bridging behaviors and the mode Ⅰ interlaminar fracture of multi-pinned laminates by changing holding temperatures and times of cure. The results reveal that a low holding temperature for a long time decreases the cure-induced Z-pin/composite interfacial cracks, thus generating larger Z-pin energy dissipation and a better specimen’s load-carrying capacity. Compared with 403 K for 150 minutes, the Z-pin energy dissipation and interlaminar fracture toughness increased by 32.22 % and 38.82 % by holding at 383 K for 200 minutes. Mesoscale and macroscale models were developed to predict the cure-induced Z-pin interfacial conditions, Z-pin bridging behaviors, and reinforcement efficiency. Combining the experiments and numerical illustration, this paper presents the possibility of optimizing the Z-pinning performances through the curing profiles.
复合材料层合板采用z形钉钉技术来提高层间性能。然后对z -钉接复合材料进行固化,以获得大大增强的层间断裂韧性。然而,关于固化对z -钉合板力学性能影响的研究很少。本文通过多尺度实验和模拟研究了不同保温温度和固化次数对多钉层合板的Z-pin桥接行为和Ⅰ层间断裂模式的影响。结果表明,长时间低温保温可以降低Z-pin/复合材料界面的固化裂纹,从而产生更大的Z-pin能量耗散和更好的试样承载能力。与403 K保温150 min相比,383 K保温200 min后z销的耗能和层间断裂韧性分别提高了32.22%和38.82%。建立了中尺度和宏观模型来预测固化诱导的Z-pin界面条件、Z-pin桥接行为和增强效率。结合实验和数值说明,提出了通过固化型态优化z形钉钉性能的可能性。