孔隙率对复合材料单向板横向力学性能的影响

在考虑纤维和孔隙随机分布的情况下,通过随机算法生成包含孔隙的代表性体积单元Representative Volume Element(RVE)。对生成的RVE建立有限元模型,引入基体的塑性本构模型和界面的双线性本构模型,采用有限元方法研究了孔隙率对碳纤维/环氧树脂复合材料单向板横向力学性能的影响。研究显示,孔隙随机分布对横向力学性能的影响不是很大;当孔隙率不超过临界值时,孔隙对横向力学性能的影响相对较小;当孔隙率超过临界值后,材料横向弹性模量、横向拉伸强度和横向压缩强度都会有较大的下降。

THE INFLUENCE OF VOID CONTENTS ON TRANSVERSE MECHANICAL PROPERTIES OF UNIDIRECTIONAL COMPOSITES

Considering the random distribution of fibers and voids,the representative volume element (RVE) of the composites microstmcture with random voids is generated by random algorithm.Then,by creating finite element model of RVEs and considering the elasticity-plasticity of matrix and bilinear traction-separation law for interface,the effect of void contents on transverse behavior of unidirectional composites is simulated by the finite element analysis.It is found that the effect of random distribution of voids is small on transverse properties.When void content is less than critical value,the influence of voids on transverse properties is weak relatively.When void content is more than critical value,the reduction in transverse modulus,transverse tension strength and transverse compression strength becomes signiticant.