三维编织复合材料力学性能研究现状

对三维编织复合材料的力学性能研究现状进行了综述,研究内容大致归纳为细观结构特征研究、有限元仿真研究及实验研究。细观结构研究主要是研究单胞几何模型的建立和编织工艺与单胞结构模型的关系。有限元研究主要集中在利用有限元软件对细观结构模型进行力学分析、刚度强度性能预测。实验研究是运用实验的方法对材料的拉伸性能、弯曲性能及疲劳性能进行研究,并分析编织工艺参数和温度对其力学性能的影响。最后,对目前研究中存在的问题和今后的发展趋势进行了展望。     

三维五向编织复合材料工字梁弯曲性能研究

对四步法三维五向编织工字梁结构的弯曲性能进行了数值分析和实验研究。首先根据三维五向编织复合材料细观结构模型对材料进行刚度预测,讨论编织参数对材料性能的影响;在此基础上,将预测得到的单胞力学性能应用到宏观结构上,建立三维五向工字梁有限元模型,对其弯曲性能进行数值分析;最后采用RTM工艺制作工字梁试件进行四点弯曲试验,将结果与有限元计算结果进行对比。结果显示,编织参数的变化对三维五向编织复合材料的性能有着较大影响,有限元分析结果与试验结果基本一致。     

三维编织复合材料的细观结构与力学性能

归纳、梳理了三维编织复合材料细观结构表征方面较有代表性的单胞模型,分析、比较各结构模型的优缺点,从理论分析与试验测试两方面总结三维编织复合材料刚度和强度性能的研究成果与进展,探讨了细观结构表征与力学性能预报中存在的主要问题,并展望今后的研究重点与发展方向。     

编织结构复合材料力学性能的测试与分析

对四步法三维编织复合材料的拉伸、压缩和弯曲等性能进行了实验研究,得到了该材料的主要力学性能参数及破坏规律.实验结果表明:三维编织复合材料具有良好的力学性能,而编织工艺和编织结构对复合材料的性能有较大的影响.这些结果为进一步研究复合材料的强度失效问题奠定了实验基础.     

三维四步法纱线不同运动式样编织复合材料力学性能分析

通过对三维四步法1×3式样、1×5式样编织复合材料几何细观结构的研究,采用六边形纤维束截面假设,建立了一种三维四步法1×3式样、1×5式样编织复合材料有限元3D模型,对其拉伸、压缩和剪切力学性能进行了理论分析,并与试验结果进行了对比,验证了有限元3D模型的准确性。     

二维编织复合材料管件力学性能研究进展

综述了近年来国内外对二维编织复合材料管件力学性能的研究成果及研究进展,主要包括力学性能实验研究、结构几何模型和数值仿真研究。在实验研究中介绍了二维编织复合材料管件的能量吸收性能及弹性性能,同时重点介绍了编织角及编织结构的变化对复合材料各种性能的影响的最新研究进展;在结构几何模型研究中,以细观结构、宏-细观结构模型研究为主,详细介绍了当前流行的建模方法;在数值仿真研究方面,介绍了研究人员根据二维编织成型原理以及纤维在复合材料中的取向建立的实体模型仿真分析。最后,总结当下研究中存在的问题,并对未来研究趋势进行展望。     

动力有限元在三维编织复合材料弹道冲击性能研究中的应用

三维编织复合材料具有高的层间剪切强度,高的损伤容限和显著的抵抗裂纹扩展的能力。三维编织复合材料弹道性能的研究一般局限于实验观察阶段。本文运用数值计算方法对三维编织复合材料细观结构有限元模型进行弹道冲击性能研究,得出了合理的结果,说明了这种方法的有效性。     

三维编织压电陶瓷基复合材料有效电弹性性能有限元分析

基于三维编织预制件的细观结构,建立了三维编织压电陶瓷基复合材料位移-电耦合场有限元模型,利用电弹性场体积平均思想和有限元方法研究了周期分布三维编织压电陶瓷基复合材料的有效电弹性性能。通过对代表性体积单元施加位移载荷和电载荷边界条件,预测了不同纤维体积分数下三维编织压电陶瓷基复合材料的有效弹性常数、压电常数和介电常数。计算结果表明,三维编织压电陶瓷基复合材料可显著改善压电陶瓷的整体力学性能,且保持了较好的电学性能。     

超声评价碳/环氧三维编织复合材料的实验分析

 本文采用超声回波法对碳/环氧三维编织复合材料进行超声A 扫描,结合对超声定位的缺陷区域进行细观形 貌解剖分析,研究了超声回波波形和三维编织复合材料细观形貌特征的对应关系。在考虑碳纤维单丝分布及纤维束 和树脂界面状态的基础上,利用经验的波形分析法讨论了超声波在三维编织复合材料中的衰减。实验研究结果表明 ,超声回波特征和三维编织复合材料缺陷有对应关系,超声A 扫描波形特征分析可用于碳/环氧三维编织复合材料 的无损检测及其缺陷的初步评价。     

三维机织复合材料力学性能分析与研究

通过对三维机织复合材料几何细观结构的研究,分析了三维机织复合材料的力学性能,采用椭圆形纤维束截面假设并结合实际的纱线形态建立了一种新的三维机织复合材料力学模型,对三维机织复合材料的拉伸、压缩和层间剪切强度进行了理论分析,并与实验结果进行了对比,验证了力学模型的正确性。     

Effect of interfacial properties on the thermophysical properties of 3D braided composites: 3D multiscale finite element study

In this article, a new three‐dimensional (3D) finite element modeling is developed to investigate the effect of interfacial properties on the thermophysical properties of 3D braided composites. The yarn is considered as uniaxial fiber‐reinforced composites, and its effective thermophysical properties are obtained by a representative volume cell constructed using the collision algorithm. In addition, based on the periodic nonadiabatic temperature boundary conditions and displacement boundary conditions, the thermophysical properties of 3D braided composites are predicted and compared with the experimental results, in which a good agreement is achieved. A comparison is conducted between the effect of interfacial properties on the thermophysical properties of 3D four‐directional (4D) braided composites and that of 3D5D braided composites. The results acquired show that the interfacial properties are significant factors that affect the thermophysical properties of 3D4D braided composites, but they have no obvious effects on the thermophysical properties of 3D5D braided composites. POLYM. COMPOS., 35:1690–1700, 2014. © 2013 Society of Plastics Engineers     

三维编织复合材料的力学性能

三维编织复合材料是一种新型结构材料，具有优异的力学性能。本文综述了三维编织复合材料力学性能的部分研究进展，并对发展趋势进行了简要的评价与展望。     

Experiments and progressive damage analyses of three‐dimensional full five‐directional braided composites under three‐point bending

Experimental and numerical studies on the bending properties of three‐dimensional full five‐directional (3DF5D) braided composites are presented in this article. Three‐point bending tests of the braided specimens with different braiding angles were first preformed. Then, the full‐scale specimen model was constructed and a strength analysis method based on repeated unit‐cell (RUC) model was established to describe the strength characteristics of the 3DF5D braided composites. The differences between yarn configurations in corner, surface and interior RUCs were considered and continuum damage models were introduced into the components such as yarns and matrix of the RUCs in the method. This linked the macroscopic nonlinear response with the damages in the microstructures. Good agreements were achieved in the load‐deflection curves and damage morphology between experimental and numerical results. POLYM. COMPOS., 37:2478–2493, 2016. © 2015 Society of Plastics Engineers     

纤维编织增强酚醛树脂基热防护材料研究进展

介绍了二维织物、2.5维织物、三维织物等纤维预制件的结构特性,分析总结了各种纤维预制件的发展及研究状况,综述了三维编织增强酚醛树脂基热防护材料及其树脂传递模塑成型工艺研究进展。总结了目前研究中存在的问题,并对未来的研究趋势进行了展望。指出三维编织复合材料是不分层的整体结构,其比强度、比模量高,力学性能和功能性优异,开展编织复合材料力学性能有限元分析、结构与功能一体化设计、低成本制造工艺等研究是十分迫切的。在此基础上,开展多种编织工艺、多种纤维混合编织也是新的研究方向,特殊形状的一次性编织复合材料的力学性能研究有待进一步深入。     

三维编织碳纤维尼龙复合材料的探索性研究

本文论述了根据碱催化阴离子聚合原理、用液态原位聚合方法制备三维编织碳纤维尼龙复合材料的成型工艺过程,测试并分析了其力学性能及其成型过程中的主要影响因素.结果表明,该复合材料的性能明显优于长碳纤维尼龙复合材料.     

Three‐dimensionally braided carbon fiber–epoxy composites,a new type of material for osteosynthesis devices. I. Mechanical properties and moisture absorption behavior

In recent years, three‐dimensionally (3D) braided composites have attracted a great deal of attention because of their high‐impact damage tolerance and fatigue life, superior fracture toughness, and so forth, and have been used in aeronautics, military, and transportation. These advantages make them strong candidates for osteosynthesis devices. In this study, 3D braided carbon fiber–epoxy (C_3D/EP) composites were produced via a simple vacuum impregnation technique. The load‐deflection curve, mechanical properties, and influence of fiber volume fraction, braiding angle, and axial reinforcing fibers were examined to determine their suitability for internal fixation devices. It is found that the C_3D/EP composites have excellent toughness and do not show brittleness when fractured because of their relatively high void content. The flexural, shear, and impact strengths of the C_3D/EP composites are excellent. It was shown that a C_3D/EP composite with a stiffness similar to load‐bearing bones can be made while maintaining enough strength. It is concluded that a relatively higher void content and braiding angle is more suitable for the C_3D/EP composites from the viewpoint of requirements of fracture fixation materials. The moisture absorption behavior and changes in mechanical properties caused by moisture uptake were evaluated. Results show that absorbed moisture slightly decreases mechanical properties of the C_3D/EP composites. Contrary to the unreinforced epoxy, the moisture absorption behavior of the C_3D/EP composites cannot be described with Fick's law of diffusion, probably because of the presence of voids and/or 3D fiber structure. The exact mechanisms should be proposed in further investigations. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 85: 1031–1039, 2002