Effect of fiber orientation on Mode-I delamination resistance of glass/epoxy laminates incorporated with milled glass fiber fillers

The present work is focused on improving the Mode-I delamination resistance of glass/epoxy composite laminates with milled glass fiber fillers. The influence of the interface fiber orientation and also the effect of fillers on the Mode-I interlaminar fracture toughness was experimentally investigated and the results were correlated with the baseline glass/epoxy samples. It was observed that the dispersion of milled glass fiber fillers by weight of 5% of the epoxy matrix into the resin rich domain improved the fracture toughness efficiently, in all the cases of interface fiber orientation. This improvement in interlaminar fracture toughness was due to additional toughening mechanisms through crack deflection, filler debonding, filler interlocking/bridging and filler pullout. The results showed that incorporation of milled glass fiber filler enhanced the GIC Initiation and GIC Propagation fracture toughness by 102% and 50% in 0-0° interply orientations over the baseline glass/epoxy samples. Besides, fracture surface analysis of the samples using Scanning Electron Microscope (SEM) indicates that the different damage mechanisms correspond to the deviation in fracture toughness.