Energy absorption capacity of pre-homologated polyamides against fire for 3D-printing

Abstract

Recent advances in developing new concepts for railway structures demand newlightweight structure concepts not only to reduce their energy consumption but also toreduce the load transmitted to the rail track. Fibre-reinforced polymers (FRP) have gainedattention in the railway industry due to their lightweight properties, specific strength andstiffness, and corrosion resistance. Most published studies on the design of lightweightstructures, for body and rolling stock, focus on continuous fibre-reinforced thermosetpolymers (cFRP). However, derailment risk and fire safety must never be compromised dueto this weight-reduction process.Therefore, new structure designs must be impact resistant and the materials must complywith EN-45545-2. A wide variety of fire protection, self-extinguishing or flame retardantsystems for composite components and structures are available in the literature. Theinfluence of flame retardant loading on the impact properties of a continuous carbon fibrereinforced polyamide 6 manufactured by 3D printing of continuous carbon fibre prepregs(FFF) has been analysed in the present work. The impact characterisation of a sandwichpanel with a bio-inspired cellular core was carried out in this study. From the results, it hasbeen concluded that the pre-homologated materials (Onyx-FR and cCF/PA-FR) have a similarenergy absorption capacity (EAS) to that of the reference reinforced polyamide 6 used in 3Dprinting processes - FFF.