In this study, flexural tests using both thermoset and thermoplastic carbon fiber reinforced plastics (CFRP) laminates with varied ply thicknesses were conducted in order to evaluate the effect of ply thickness and matrix resin on the flexural properties of thin ply composites. Results confirmed that the flexural properties were improved by decreasing the ply thickness in both thermoset and thermoplastic laminates. Furthermore, in-situ observation of specimens during the test revealed that short delamination occurred in the carbon fiber carbon fiber reinforced thermoplastics (CFRTP) thin ply laminate, while long delamination was observed in case of carbon fiber reinforced thermosets (CFRTS). This indicates that damage progressions of the laminates were influenced by the toughness of the matrix resin. On comparing the in-situ strength in the first ply failure calculated from the classical laminate theory in the thin and thick ply laminates, it was confirmed that high damage resistance was caused by higher in-situ strength in each layer in the thin ply laminate.
