LAUSR

Nowadays, using three dimensional fabric as a reinforcement part in the composite has been increased. Non-crimp three dimensional orthogonal woven fabric is a subgroup of 3D woven fabrics that in this study was used to fabricate composite preforms. The fabrics were produced by glass yarn in two different fiber volume fractions. All fabric preforms were utilized to produce composites with polyester and epoxy resins. To compare the torsional behavior of the composites, a torsion test was applied to all samples and torque-revolution curves from the experimental results were compared together. Results showed that composites that were fabricated by epoxy resin have more torsional strength in comparison with composites in that their matrix is polyester resin. Moreover, preforms with high fiber volume fractions showed high torsional strength in each type of matrix. The torsion strength of high volume fraction for polyester matrix was 47.34 KPa, however for the sample with epoxy matrix the torsion strength was determined 81.26 KPa. Furthermore, a multiscale finite element model was applied to calculate elastic constants and predict the torsional behavior of the composites. The numerical results were compared with experimental results that a good agreement between numerical and experimental results was observed. Therefore, the proposed model can predict the torsional behavior of the composite with different fiber volume fractions.