Modeling tensile behavior of 3D orthogonal woven green composites considering variability of natural fibers

Abstract

Over the past few decades, ecological concerns resulted in an interest in using natural fibers such as flax and hemp as a reinforcement in composite materials. However, the inherent variability of their mechanical and physical properties complicates predicting the mechanical performance of their preforms and hence composites. This research introduces a novel approach in modeling natural fiber composites. To the best of the author's knowledge, this is the first model that considers the variability of natural fibers' properties used in 3D orthogonal woven composites. Measured properties of fibers, yarns and resin in addition to geometrical parameters were used as inputs while the entire Load-Elongation curve of the composite was the output of the model. This model is generalized for any weave design and can be applied for hybrid structures. The model was verified experimentally using preforms from flax and hemp fibers. The model verification showed that there is a better agreement between the predicted and experimental results when using the properties of yarns as input rather than fibers.