The Laminar Effect of FRP-FRTP or CFRP-FRTP Composites on Flexure Behavior

Abstract

The effect of lamination on flexure behavior of Fiber-Reinforced Plastic Composites was described emphasizing flat laminate and the FRP-FRTP or CFRP-FRTP composites. Examined flexure test variables were layup sequences, span to depth ratio, number of plies and loading speed. At the bending rate of 0.1cm/min. to 1.8×10⁴cm/min., a correlation of statical flexure with Charpy impact was studied. Furthermore, remarkable improvements in properties of Plastic Composites were obtained. The results are as follows.
(1) The reinforced polyester laminated composites demonstrated an increase in ultimate flexural strength with increasing rate of bending. The Charpy impact strength per unit cross section area has remarkably increased with increasing laminate depth or number of plies. The effect of notch on flatwise Charpy impact strength was negligible.
(2) FRP-FRTP composite, fabricated with PVC-GF and Epoxy-GF layers, has shown great improvements in flexural and impact strengths. Flexural strength increases two times of that of FRTP only, and flexural modulus of elasticity increases to almost 1.5 times. Charpy impact strength also increases to two times.
(3) CFRP-FRTP composite, fabricated with Nylon 6-GF and Epoxy-Carbonfiber layers, shows higher distortion energy than FRP-FRTP composites. The flexural and impact strength and the flexural modulus are markedly improved by laminating with CFRP. Charpy impact strength increases more than 4 times, and flexural modulus increases almost 3.5 times of that of FRTP.