Impact damage resistance of carbon fibre/epoxy composite laminates containing short Kevlar fibres

The impact damage resistance of carbon fibre/epoxy matrix composites containing short Kevlar® fibres as the interlayer material was studied. Instrumented low-velocity impact tests were conducted at several temperatures to study the impact fracture and damage mechanisms. The experimental results indicate that short Kevlar fibres improved the impact damage performance. Distinct damage patterns were observed on the front and back faces of the specimens tested at two extreme temperatures; -60°C and 130°C. Cross-sectional microscopy was performed to evaluate sub-surface damage; optical and scanning electron microscopy were used to study the fracture mechanisms of the laminates impacted at different temperatures. The main contribution of the interlayer material to the improvement in impact resistance was the enhanced fibre-bridging with the short Kevlar fibres at the interlaminar regions.