FLEXURAL BEHAVIOUR OF POLYURETHANE FOAM FILLED HIGH PERFORMANCE 3-D WOVEN I-BEAM COMPOSITES

Abstract

Sandwich composites have several industrial applications due to their lightweight and high specific strength. Strengthened polymeric foams by nano-reinforcement have high contact surface between core and face-sheets bring advantages including elimination of the face-sheet and core debonding and water accumulation in the structure. Furthermore, filling area between the web and the flanges of I-beams with polymeric foams can enhance strength and load bearing capacity while assisting structural integrity. In this work, polymeric foams and 3-D woven composites are combined to obtain high-performance I-beam composites. Foaming process of neat and 0.1 wt.% carbon nanotube (CNT) reinforced polyurethane foams was achieved in the area between the web and the flanges of 3-D woven glass fibers by a novel free-rise foaming method. Composites were fabricated by the vacuum infusion method, and three-point bending tests were performed to evaluate the increment in load bearing capacity, flexural strength and flexural modulus. © 2022 Küçükkalfa et al.