Effect of thickness variation on static behaviour of carbon fiber reinforced polymer multidirectional laminated composite

This paper illustrates the thickness effect on theoretical and experimental static strength of cross-ply [0, 90] Carbon fiber reinforced polymer (CFRP) composite. Three cross-ply carbon fiber/epoxy (IMA/M21) laminate with stacking sequence [0, 90]_3S, [0, 90]_2S, and [0, 90]_S were fabricated using vacuum assisted resin transfer molding technique. The fiber volume fraction of the laminates was 59%. The experimental tensile and compressive strength was evaluated using a servo-hydraulic universal testing machine with a constant crosshead speed 1 mm min⁻¹. The experimental result was compared with theoretical strength calculated using Classical Laminate Theory (CLT). The failure analysis of fractured specimens was carried out using scanning electron microscopy and optical microscopy. The fiber fracture, matrix cracking, delamination and debonding of the fiber-matrix interface were the most conquered mode of failure. The experimental and predicted tensile strength using the CLT approach showed slight variation. The tensile strength decreased with increase in laminate thickness whereas compressive strength increased with an increase in thickness. (paper)