Temperature effect on impact response of flax/epoxy laminates: Analytical, numerical and experimental results

Polymer composite materials are widespread in most industrial fields, such as automotive, civil engineering, marine, wind energy, packaging and sports, and their demand is increasing since they have the potential of combining high mechanical properties with the lightness of the components. However, due to their nonbiodegradable nature, they are not easy to dispose of at the end of the components' life cycle. To overcome this issue, vegetable fibers represent prospective substitutes to traditional reinforcements since they are able to provide good mechanical properties, together with low cost, renewability, and biodegradability. From the experimental point of view, the present work provides a complete characterization of the impact behavior of twill flax/epoxy composites in a wide range of temperatures and assesses the effect of the aforementioned impact temperatures on the residual flexural properties of these composites. Moreover, for the impact tests, analytical and numerical models are used to predict a threshold impact load for the damage onset and extent, and to draw an approximation of the load-displacement curve. Good agreement was found when comparing the derived analytical and numerical load curves with the experimental ones.

Automated summary

Polymer composite materials are widely used in various industrial fields, with vegetable fibers showing potential as substitutes for traditional reinforcements. The study provides a comprehensive characterization of the impact behavior of twill flax/epoxy composites and evaluates the effect of impact temperatures on residual flexural properties. Analytical and numerical models were able to accurately predict the impact load threshold and draw load-displacement curves that closely matched experimental results.