Mechanical behavior of unidirectional composites with hexagonal and uneven distribution of fibers in the transverse cross-section

Abstract

Uneven distribution of fibers can adversely affect the mechanical behavior of unidirectional composites. A micromechanical model based on finite element analysis is presented to evaluate elastic and strength properties of such composites under normal loading. Analysis starts with identification of micro unit cells/micro repetitive unit cells and/or representative volume elements. Because of uneven distribution/random distribution of the fibers, fiber volume fraction can be different for different micro unit cells present at different locations in the transverse cross-section of the unidirectional composite. Configuration of the micro unit cell is worked out at the outset considering the fiber distribution having the hexagonal arrangement, but with different volume fraction at different locations. For such micro unit cells, elastic and strength properties are obtained based on finite element analysis starting with the elastic and strength properties of fiber and matrix. With the properties obtained for different micro unit cells, elastic and strength properties of the unidirectional composite with micro unit cells having hexagonal arrangement of fibers with different volume fraction at different locations in the transverse cross-section are determined. Further, elastic and strength properties are evaluated for micro unit cells with uneven distribution of fibers in the transverse cross-section.

Numerical simulation for strain rate and temperature dependence of transverse tensile failure of unidirectional carbon fiber-reinforced plastics

“…The study of transverse failure of unidirectional FRP has been conducted by many researchers. [3][4][5][6][7][8][9][10][11][12][13][14][15][16] Fiedler et al 3 investigated the transverse failure of unidirectional CFRP using mechanical and thermomechanical test methods and finite-element analysis and described the failure dependence of the matrix on the actual stress state. Naderi et al 4 conducted a micromechanical analysis of the influence of fiber-matrix interface fracture properties on the transverse tensile behavior of FRP using representative volume element (RVE).…”

A micromechanical study on shear performance of unidirectional composites with randomly distributed fibers in the transverse cross‐section

“…In real-world situations, it is common for the fiber distribution in the cross-section of UD composites to be random. In this context, several research articles [29][30][31][32][33][34][35][36] has explored the strength characteristics under normal loading conditions of such composites when the fibers are randomly distributed across the cross-section. These studies have proposed different techniques to create random fiber distributions in the crosssection and have analyzed their influence on the UD composites mechanical behavior.…”