Experimental and numerical characterization of E-glass/epoxy plain woven fabric composites containing void defects

The presence of voids in woven fabric composite (WFC) significantly affects the mechanical and thermomechanical properties. Void defects are introduced during the resin infiltration process due to various controlling parameters involved in the curing process, i.e., pressure, temperature, resin flow etc. In this study, the mechanical constants of 2D woven fabric composite were experimentally determined. A finite element (FE) based representative volume element (RVE) model has been validated against these experimental results. A multiscale-based FE model has been developed, and periodic boundary conditions are applied to the RVE model to evaluate the homogenized thermomechanical properties of WFC containing void defects. Present numerical model incorporates the geometrical microstructures of the post-cured woven composite and void contents obtained from X-ray microtomography. The influence of void defect and resin infiltration have been incorporated to evaluate the thermomechanical properties of plain WFC. A parametric study has been carried out with respect to the variation of void defects on thermoelastic properties of E-glass/epoxy plain WFC. The variation of void defects has been considered in micro and mesoscale models. Monte Carlo simulations further quantified the effects of void content on the thermomechanical constants of WFC. The presence of voids has been observed to have significant influences on the thermomechanical constants of yarn and woven fabric composites.