High-velocity impact behavior of nonwoven mats and unidirectional prepreg hemp and flax fibers reinforced hybrid biocomposites

Abstract

High specific impact strength and stiffness are demanded in various applications, leading to the widespread utilization of fiber-reinforced polymers. Synthetic fiber-reinforced polymers have been used to meet these engineering requirements. However, the current popularity of biocomposites arises from their environmental friendliness, ease of availability, and affordability, making them a favored alternative to synthetic-based fiber-reinforced polymers. An assessment must be conducted to determine whether biocomposites can replace their synthetic fiber counterparts, necessitating a thorough investigation into their impact behavior. This study aims to unveil the impact performance of hybrid biocomposites made from unidirectional prepregs comprising flax/polypropylene fibers and nonwoven mats composed of hemp/polypropylene fibers. The impact performance of hybrid biocomposites has also been studied concerning the number of layers and stacking sequence. Eight different designs of biocomposite plates are manufactured through compression molding and subsequently subjected to high-velocity impact tests. Additionally, numerical simulation using the FEM is utilized to model and analyze the impact behavior of one specimen. The test results indicate that each design possesses unique characteristics and impact behaviors differ.

Highlights Adding prepreg significantly improved mechanical performance in the biocomposites. Performance enhancement varies depending on the stacking sequence. Adding multiple layers of UD prepregs enhances mat impact performance. Numerical simulations validate the Tsai-Wu criterion for impact testing.