Elastic properties of unidirectional fiber-reinforced composites using asymptotic homogenization techniques

Abstract

The objective of this work is to use an asymptotic homogenization numerical model to obtain elastic properties of unidirectional fiber-reinforced composites. Square and perfect hexagonal unit cells are employed, and the influence of the fiber volume fraction over the homogenized elastic properties is studied. The effectiveness of the predictions is assessed by comparisons to experimental properties, and also another micromechanical model based on a representative volume element. The composites E-Glass 21xK43 Gevetex (glass fiber)/LY556/HT907/DY063 (epoxy matrix) and AS4 (carbon fiber)/3501-6 (epoxy matrix) were studied and good agreement between experimental and numerical predictions was found. Discrepancies between experimental and numerical data are explained in terms of simplifications considered in the homogenization model. An adjustment of properties here performed, based on varying fiber volume fractions, showed to be effective to physically represent the studied fiber composites in a micromechanical stress model based on asymptotic homogenization, developed to estimate failure envelopes of such materials.

The Elastic Properties of Unidirectional Bamboo Fibre Reinforced Epoxy Composites

“…The large difference in the Young's moduli values between bamboo fibre and epoxy-resin matrix ( Table 2) could be resultant for such considerable variation in the values of in-plane shear modulus for FEM and analytical methods. Closely similar results are also reported by de Macedo [38]. Fig.11 shows the short bamboo fibre composite modelled using the Halpin-Tsai, ROM and RVE model.…”

“…These factors may also contribute in poor interfacial bonding between fibre and matrix material, thereby generating a partially weak structure. The idealizations presented by mathematical model are influenced by many factors including [i] the perfect bonding interface between fibre and matrix, [ii] no fibre waviness [iii] all fibres are in perfect alignment and parallel to the periodicity and [iv] fibres are perfectly distributed inside the matrix resulting in a larger difference between analytical, FEA model and experimental work [38]. In addition, the interface properties between fibre and matrix as well as the deformities in the composites are not considered for the most natural fibre composite's FEA models [41].…”

Mechanical characterization and asymptotic homogenization of 3D-printed continuous carbon fiber-reinforced thermoplastic

“…Although these approaches can provide good results for the mechanical properties in the fiber direction, to properly estimate the matrix properties it is needed to evaluate the transverse properties which are very underestimated in these approaches. In this context, the present work has applied a consistent mathematical technique, viz., asymptotic homogenization, which provides very good results in predicting elastic mechanical properties of composite materials in both longitudinal and transverse directions [40].…”

Effect of TiO2 nano-filler in mechanical and free vibration damping behavior of hybrid natural fiber composites

“…Natural fiber reinforcements with various matrices are studied in researches, in that about 15-20% are used for the application of automobile field, and more than 50% for the construction applications. Other applications are in the field of tiles, furniture and industrial applications [3][4][5][6].…”