碳纤维的形状效应和界面效应对复合材料等效热弹性性能的影响  

Carbon Fiber Shape and Interphase Effects on the Equivalent Thermoelastic Properties of Composites

作　　者：孙洋 范振杰 刘马宝[2] SUN Yang;FAN Zhenjie;LIU Mabao(Department of Engineering Mechanics,School of Civil Engineering and Architecture,Xi’an University of Technology,Xi’an 710048,P.R.China;State Key Laboratory for Strength and Vibration of Mechanical Structures,School of Aerospace Engineering,Xi’an Jiaotong University,Xi’an 710049,P.R.China)

机构地区：[1]西安理工大学土木建筑工程学院工程力学系,西安710048 [2]西安交通大学航天航空学院复杂服役环境重大装备结构强度与寿命全国重点实验室,西安710049

出　　处：《应用数学和力学》2025年第4期495-504,共10页Applied Mathematics and Mechanics

基　　金：国家自然科学基金(12302266);陕西省自然科学基金(2021JQ-466)。

摘　　要：碳纤维增强聚合物基复合材料是一种应用广泛的工程材料,其性能优异与否直接影响着工程应用的安全和可靠性.碳纤维的形状效应和界面效应被认为是影响碳纤维复合材料力学性能的重要因素.因此,开展碳纤维形状效应和界面效应的深入研究,对于碳纤维增强聚合物基复合材料的优化设计和工程应用具有重要意义.为了揭示碳纤维形状效应和界面效应对碳纤维复合材料热弹性性能的影响,该文采用细观力学有限元方法建立了一个代表性体积单元(RVE)模型,通过模拟材料内部微观结构,研究了不同碳纤维形状和含量、界面相含量和界面相性能对碳纤维复合材料等效热弹性性能的影响.结果表明,碳纤维形状效应对复合材料宏观纵向弹性模量和纵向热膨胀系数几乎没有影响,而对横向弹性模量、横向剪切模量、纵向剪切模量和横向热膨胀系数影响较大,尤其是随着碳纤维含量的增加影响更为明显.随着界面相含量的增加,当界面效应表现为硬界面效应时,复合材料的纵向与横向弹性模量均会随之增加,而当界面效应表现为软界面效应时,复合材料的纵向与横向弹性模量均会随之减小.当界面相热膨胀系数小于基体热膨胀系数时,复合材料的纵向与横向热膨胀系数均会随界面相含量的增加而减少,而当界面相热膨胀系数大于基体热膨胀系数时,复合材料的纵向与横向热膨胀系数均会随界面相含量的增加而增加.Carbon fiber reinforced polymer matrix composites are widely used engineering materials,and their performances directly affects the safety and reliability of engineering applications.The carbon fiber shape and interphase are considered as important factors affecting the properties of composites.Therefore,conducting in-depth research on the carbon fiber shape and interphase effects on the thermoelastic properties of composites is of significance for the optimization design and engineering application of carbon fiber composites.A representative volume element(RVE)model was established with the finite element method.The internal microstructure of the composite was simulated,and the influences of different fiber volume fractions and shapes,interphase volume fractions and behaviors on the equivalent properties of fiber composites,were investigated.The results show that,the fiber shape has little effect on macroscopic longitudinal Young’s modulus and the longitudinal thermal expansion coefficient of the composite,but has a great influence on transverse Young’s modulus,the transverse shear modulus,the longitudinal shear modulus and the transverse thermal expansion coefficient,especially with the increase of the fiber volume fraction.Longitudinal and transverse Young’s moduli of the composite will increase with the interfacial volume fraction,while the interphase effect is manifested as a hard one,but will decrease while the interphase effect is manifested as a soft one.When the interfacial thermal expansion coefficient is less than that of the matrix,both the longitudinal and the transverse thermo-parameters of the composite will decrease with the interfacial volume fraction;but when the interfacial thermal expansion coefficient is greater than that of the matrix,both the longitudinal and the transverse thermo-parameters of the composite will increase with the interfacial volume fraction.

关 键 词：碳纤维复合材料 细观力学 形状效应 界面效应 热弹性性能 

分 类 号：O343[理学—固体力学]