Investigation of Micro-Scale Stress Distributions and Concentrations In Hybrid Fiber-Reinforced Composites

Abstract

Hybrid composite materials are a specialized version of composite materials that constitute at least two different fiber materials. Hybrid composites are promising materials for various engineering applications. These materials can be specialized by selecting fiber materials that suit best with application field. Hybrid composites are employed in many fields, such as aerospace, automotive, construction, etc. Due to their application areas and the high potential of enlargement of their application fields in the future, having sufficient knowledge of these materials is essential.

Due to their complex internal structure, the effect of different parameters on these materials has been subjected to studies intensively. In general, studies focus on axial direction, parameters, and impact on axial load-carrying capability. This thesis study focuses on effects of different structural parameters in transverse direction and their effect on structure. The main aim of this study is investigation of different characteristic structural parameters of composite materials on stress distribution and stress concentrations at micro scale on hybrid composite materials composed with carbon and glass fibers.

During this thesis study, representative volume elements-both hexagonal and random RVE- utilized to model the structure. FEA modeling is used and a FEA model prepared for each investigated case for finite element modeling. Abaqus[2] program utilized for FEM modeling. To parametrize the study, a set of code used to create FEA models, Python[3, 4] program used for this process. In postprocess stage FEA output data is used as an input for normalization and stress concentration calculations and post process viewing programs, Mathcad[5] and Hyperview [6] programs are utilized for postprocess. Results of this study is aimed to use in prediction of behavior of these materials under certain loading conditions.