Understanding the impact properties and damage phenomenon of ultra-lightweight all-thermoplastic composite structures

Abstract

The current research presents the details of the impact properties of novel all-thermoplastic composite structures with different thermoplastic fabrics like ultra‐high molecular weight polyethylene (PE), ultra‐high molecular weight polypropylene (PP), and Polyester (PES) with room temperature curable acrylic Elium® (EL) thermoplastic resin. The low-velocity impact performance is studied at five energy levels (10J-50J), and the performance is compared to baseline epoxy (EP) composites, and their failure mechanisms are deduced through optical and SEM examination. PP/ELC, PE/ELC and PES/ELC all-thermoplastic composites have shown up to 34.68%, 24.46%, 15.35 % higher load carrying capability and 27%, 11.21%, 8.43% lower absorbed energy compared to PP/EPC, PE/EPC, and PES/EPC composites respectively due to the lesser damage and high toughness of the matrix. The major damage energy was found to be 10.55% higher due to the more elastic and plastic deformation mechanisms before the onset of the damage. PP/ELC, PE/ELC, and PES/ELC have shown 32%, 66.7% and 51% improvement in structural integrity as opposed to epoxy counterparts. ELC composites have shown matrix cracks, and strong fibre matrix adhesion with thermoplastic fibres properly embedded in the acrylic resin, while clean fibre pull-out and bare fibres were observed for EPC composites.