Micromechanical analysis of fiber spatial distribution influence in unidirectional composite cross-section on overall response in terms of tensile curves

Abstract

One important part of the design process of composite structures is the investigation of quality of the elementary material. There are a number of characteristics which may have the influence on the quality of the final composite material. Widely used fiber volume fraction has direct influence on mechanical properties of the resulting composite. Nevertheless, it is not the only quantity which can directly influence mechanical properties of the whole composite. It depends also on the spatial distribution of the fibers especially within the cross-section perpendicular to the fibers. This study is a continuation of a previous work which focused on the influence of the fiber spatial distribution on effective elastic constants of unidirectional lamina. This study uses the same description of the irregularity of the fiber spatial distribution (the parameter called the degree of irregularity), but focuses on the influence of this parameter on stress–strain dependencies obtained from tensile tests. Non-linear anisotropic elastic material model for fibers and elastic-plastic isotropic model with isotropic hardening for matrix are considered for finite element analyses.