Tensile Property of FRP Composites and Metallic Material through Tensile Coupon Test

Abstract

FRP and metallic materials have diverse tensile properties, requiring detailed material specifications and sample fabrication for accurate description. This study uses experimental methods to compare the tensile properties of GFRP, CFRP, Hybrid FRP, AFRP, BFRP, and MS. Mechanical testing was performed with a 50 kN UTM and flat coupon grip fixture according to EN ISO 527/ASTM D638. Results show that the average tensile strength of T-MS was highest, with 485.20 MPa, followed by T-HB (314.22 MPa). Mono FRP plate materials have shown that T-AF was the strongest among all 4 FRP plates, followed by T-CF, T-BF, and T-GF (279.43 MPa, 199.89 MPa, 198.25 MPa, and 169.51 MPa). All FRP material samples exhibit sudden fracture at different maximum strains, with GFRP providing the largest strain before fracture, while MS samples exhibit strain softening due to necking before fracture. Based on the stress-strain curves, all FRP materials behave like brittle materials, and metallic materials behave like ductile materials, which exhibit large strain before fracture. GFRP, generally, failed through breakage and fibers pulled out of resins, while CFRP failed with angled cracks, and fibers mostly remained within matrix resins. Hybrid FRP composed of GFRP and CFRP has provided failure by an inclined crack with fiber breakage and a sign of fibers pulling out of resin. AFRP material exhibits scattered cracking failure with fibers remaining within the matrix resins, while BFRP fails with shear fibers breakages with remaining matrix resin. The metallic material represented by the mild steel sample has fractured with necking, indicating clear signs of ductile failure. Mechanical testing on all FRP composites and metallic material samples has provided at least 6 mechanical property results that can be used for further study in this area.