共查询到18条相似文献,搜索用时 109 毫秒
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碳纤维三维编织复合材料的结构对拉伸和弯曲性能的影响 总被引:9,自引:0,他引:9
研究了碳纤维四步法三维四向、三维五向编织结构复合材料的拉伸和弯曲性能,以及结构参数-编织角的变化对其拉伸和弯曲性能的影响,并与层合复合材料作了对比性研究.结果表明,三维编织复合材料具有良好的力学性能,其拉伸强度可达810MPa、拉伸模量可达95.6GPa,弯曲强度可达829.03MPa、弯曲模量可达67.5GPa.同时,编织角和编织结构对复合材料性能有较大的影响.随着编织角的增大,复合材料的拉伸、弯曲强度和模量均减小;三维五向结构的拉伸、弯曲强度和模量均高于四向结构;在纤维体积含量相近的情况下,通过对编织角的设计,可以设计三维编织复合材料的性能. 相似文献
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对具有不同细观结构参数的二步法方型三维编织复合材料试件进行了轴向拉伸、三点弯曲及轴向压缩的力学性能测试,获得了这种结构材料的基本力学性能数据。针对其细观结构特点,从宏观角度分析了编织纱的种类、编织纱与轴纱的线密度之比以及编织节距长度等参数对力学性能的影响。实验和分析结果表明:二步法方型三维编织复合材料的轴纱对轴向拉伸和压缩性能起主导作用;节距长度增大,编织纱越粗,轴向拉伸强度、拉伸模量以及轴向压缩强度和模量均有增大的趋势。 相似文献
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为了研究三维四步法编织复合材料的力学性能,利用ANSYS有限元软件对材料的细观体胞模型进行数值模拟,计算三维编织复合材料的宏观弹性常数,讨论了纤维编织角和体积比对弹性常数的影响。采用不同的强度准则分别对纤维束和基体材料进行强度校核,从而得到材料发生破坏时失效单元的体积百分比。根据失效单元的分布情况分析材料的破坏机理,进而预报材料的拉伸强度。模拟计算结果与实验值吻合较好。 相似文献
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基于三维六向编织复合材料的细观结构,假设第六向纱线的截面形状为菱形,建立了三维六向编织复合材料的渐进损伤有限元模型。采用Linde等提出的失效准则,引入周期性位移边界条件,对三维六向编织复合材料的纵向拉伸应力-应变行为进行了渐进损伤数值模拟,讨论了单胞模型在纵向拉伸载荷作用下的细观损伤起始、扩展和最终失效的演化过程,并预测了材料的拉伸强度。在此基础上,进一步研究了编织角、纤维体积分数和编织纱水平取向角等参数对材料纵向拉伸力学性能的影响规律。研究结果表明,三维六向编织复合材料的轴向纱线拉伸断裂是导致其破坏的最主要因素。所得数值结果与现有试验值吻合较好,验证了该模型的有效性,为更深入研究此类材料的力学性能奠定了基础。 相似文献
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在三维全五向(Q5D)编织复合材料细观结构模型的基础上, 建立了其单胞参数化有限元模型。通过施加合理的边界条件, 计算得到了Q5D编织复合材料的弹性常数、 热传导系数和热膨胀系数, 所得结果与现有的实验数据吻合较好。在此基础上, 深入研究了纤维体积分数、 编织角等工艺参数对材料弹性性能和热物理性能的影响规律, 并将计算结果与三维四向(4D)和三维五向(5D)编织复合材料的相应结果进行了对比。结果表明, Q5D编织复合材料具有较好的力学性能和纵向导热性能, 其零膨胀结构的可设计性更强, 为进一步研究此种结构材料的强度问题和热力耦合问题奠定了基础。 相似文献
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三维全五向编织复合材料弹性性能及热物理性能的有限元分析 总被引:1,自引:0,他引:1
在三维全五向(Q5D)编织复合材料细观结构模型的基础上,建立了其单胞参数化有限元模型.通过施加合理的边界条件,计算得到了Q5D编织复合材料的弹性常数、热传导系数和热膨胀系数,所得结果与现有的实验数据吻合较好.在此基础上,深入研究了纤维体积分数、编织角等工艺参数对材料弹性性能和热物理性能的影响规律,并将计算结果与三维四向(4D)和三维五向(5D)编织复合材料的相应结果进行了对比.结果表明,Q5D编织复合材料具有较好的力学性能和纵向导热性能,其零膨胀结构的可设计性更强,为进一步研究此种结构材料的强度问题和热力耦合问题奠定了基础. 相似文献
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Composites based upon 3D textile preforms have found broad structural application. This paper presents an analytical methodology for functional composites using piezoceramic fibers in a 3D braided preform. The effective elastic, piezoelectric and dielectric properties of 2-step braided composites with a polymeric matrix have been investigated. In the analytical approach, the effective properties of the braider and axial yarns of the unit cells are determined first using a 3D connectivity model. Then, the effective properties of the 2-step braided composite are predicted using an averaging technique. Results of a numerical example illustrating the variation of elastic, piezoelectric and dielectric constants with the braider yarn angle are provided. Textile preforming technique in general offers the potential of near net shape forming and 3D fiber placement. The present work provides the analytical basis for 3D piezoceramic textile composites. 相似文献
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Dian-sen Li Jia-lu Li Li Chen Zi-xing Lu Dai-ning Fang 《Applied Composite Materials》2010,17(4):373-387
Based on the microstructure of three-dimensional (3D) four-directional rectangular braided composites, a new parameterized
3D finite element model (FEM) is established. This model precisely simulates the spatial configuration of the braiding yarns
and considers the cross-section deformation as well as the surface contact due to the mutual squeezing in the braiding process.
Moreover, it is oriented in the same reference frame as the composites, which coincides with the actual configuration of 3D
braided composites and facilitates the analysis of mechanical properties. In addition, the model investigates the relationships
among the structural parameters, particularly the braiding angle and the interior braiding angle, which were not taken into
account in the previous models. Based on the parameterized FEM, the structural geometry of the composites is analyzed and
some conclusions are drawn herein. Good agreement has been obtained between the calculated and measured values of the geometric
characteristics of braided composite samples. 相似文献
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三维五向编织复合材料纵向性能的实验研究 总被引:9,自引:2,他引:9
通过对具有不同编织结构参数的三维五向编织复合材料试件的纵向拉伸和压缩实验,分析了该类材料的纵向拉、压刚度和强度随编织工艺参数的变化规律以及材料的失效形式.三维五向编织复合材料在破坏前基本保持线弹性,纵向拉、压破坏具有脆性特征,拉伸模量和压缩模量比较接近,但拉伸强度远大于压缩强度.编织角和纤维体积含量对材料性能的影响显著,纱线粗细的影响不大.提高第五向纱线的比例,可提高材料的纵向性能.此外,研究中采用短标距薄板试件,以避免试件产生整体屈曲和端部纤维束开裂破坏. 相似文献
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Diantang Zhang Li Chen Ying Sun Yifan Zhang Kun Qian 《Applied Composite Materials》2017,24(5):1233-1250
A study is conducted with the aim of developing multi-scale analytical method for designing the composite helicopter arm with three-dimensional (3D) five-directional braided structure. Based on the analysis of 3D braided microstructure, the multi-scale finite element modeling is developed. Finite element analysis on the load capacity of 3D five-directional braided composites helicopter arm is carried out using the software ABAQUS/Standard. The influences of the braiding angle and loading condition on the stress and strain distribution of the helicopter arm are simulated. The results show that the proposed multi-scale method is capable of accurately predicting the mechanical properties of 3D braided composites, validated by the comparison the stress-strain curves of meso-scale RVCs. Furthermore, it is found that the braiding angle is an important factor affecting the mechanical properties of 3D five-directional braided composite helicopter arm. Based on the optimized structure parameters, the nearly net-shaped composite helicopter arm is fabricated using a novel resin transfer mould (RTM) process. 相似文献
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三维编织复合材料因其结构整体性好、综合性能优异,已成为航天、航空、国防领域部分主承力构件和高功能制件的首选材料。然而,三维编织复合材料结构件在服役过程中不可避免地处于高温、低温或温度急剧变化等恶劣环境,由于三维编织复合材料增强体和基体热物理性能的巨大差异将严重威胁结构尺寸的稳定性及结构使用寿命。本文主要从实验、理论和数值仿真研究三方面,综述了近年来国内外对三维多向编织复合材料热物理性能和温度效应影响下力学性能的研究成果及研究进展。首先分析了现有研究中编织工艺、编织参数、环境温度、界面、缺陷等因素对三维多向编织复合材料热传导性能和热膨胀性能的影响规律。其次以细观结构、全尺寸、多尺度模型为主分析了不同结构几何模型的区别与联系。最后探讨了高、低温环境温度和不同载荷形式对三维多向编织复合材料组分材料损伤、失效形态及热力耦合行为的影响机制,并同时总结了现有研究工作中的重点与发展方向。 相似文献
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Mechanical properties of three-dimensional braided composites 总被引:7,自引:0,他引:7
Recently developed digital element approach, which treats textile composite manufacturing process as a nonlinear solid mechanics problem, was successfully used to investigate the complicated microstructure of 3D braided rectangular preform. The yarns interaction and cross-sectional deformation, which were neglected in traditional topological model, could be analyzed exactly. Results showed that yarns inside 3D braided preform were curvy, which was opposite to the straight-yarns assumption of topological model and, yarns curvature inside the preform, which was very difficult to be explored before both experimentally and theoretically, was investigated numerically. After that, the mechanical properties of 3D rectangular braided composites, such as tensile stiffness, shear stiffness and Poisson ratio were calculated through the volume-average-compliance method. Comparison was conducted for those from the topological model and digital element approach, and topological model was found to underestimate greatly both the tensile stiffness and shear stiffness. 相似文献
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The meso-structure is important in predicting mechanical properties of the three-dimensional (3D) braided composite. In this paper, the internal structure and porosity of three-dimensional full five-directional (3DF5D) braided composite is characterized at mesoscopic scale (the scale of the yarns) using micro-computed tomography (micro-CT) non-destructively. Glass fiber yarns as tracer are added into the sample made of carbon fiber to enhance the contrast in the sectional images. The model of tracer yarns is established with 3D reconstruction method to analyze the cross-section and path of yarns. The porosities are reconstructed and characterized in the end. The results demonstrate that the cross sections of braiding yarns and axial yarns change with the regions and the heights in one pitch of 3DF5D braided composites. The path of braiding yarns are various in the different regions while the axial yarns are always straight. Helical indentations appear on the surfaces of the axial yarns because of the squeeze from braiding yarns. Moreover, the porosities in different shapes and sizes are almost located in the matrix and between the yarns. 相似文献