Mode II Interlaminar Fracture Toughness of Woven Carbon/Epoxy Laminates Fabricated using VARTM

摘要

The present study investigates the influence of specimen width, thickness andrnmethod of crack initiation on Mode II Interlaminar Fracture Toughness (MII-IFT) ofrnwoven composite laminates. Three laminates with 16-ply, 20-ply, and 24-plyrnthicknesses were fabricated using a Vacuum Assisted Resin Transfer Moldingrn(VARTM) technique with a plain weave carbon fiber fabric and epoxy resin. Thernlaminates were manufactured with a crack at the center plane extending 44 mm alongrnthe length End Notch Flexure (ENF) testing was performed to characterize the MIIIFTrnof the prepared laminates. Samples with 13mm, 19mm, 25mm width and withrnthree types of pre-cracking such as No-Crack, Mode-I crack, Mode-II crack werernexamined. It was found that the effect of width on MII-IFT is minimal as compared tornthe thickness. It was also found Mode-II pre-cracking can have significant effect onrnthe MII-IFT. A 25 mm wide and 4.5 mm thick sample without any pre-crackingrnresulted in the maximum MII-IFT of 1.39 KJ/m^2.