Impact and post-impact damage characterisation of hybrid composite laminates based on basalt fibres in combination with flax, hemp and glass fibres manufactured by vacuum infusion

Abstract

The impact and flexural post-impact behaviour of ternary hybrid composites based on epoxy resin reinforced with different types of fibres, basalt (B), flax (F), hemp (H) and glass (G) in textile form, namely FHB, GHB and GFB, has been investigated. The reinforcement volume employed was in the order of 21–23% throughout. Laminates based exclusively on basalt, hemp and flax fibres were also fabricated for comparison. Hybrid laminates showed an intermediate performance between basalt fibre reinforced laminates on the high side, and flax and hemp fibre reinforced laminates on the low side. As for impact performance, GHB appears to be the worst performing hybrid laminate and FHB slightly overperforms GFB. In general, an increased rigidity can be attributed to all hybrids with respect to flax and hemp fibre composites. The morphological study of fracture by SEM indicated the variability of mode of fracture of flax and hemp fibre laminates and of the hybrid configuration (FHB) containing both of them. Acoustic emission monitoring during post-impact flexural tests confirmed the proneness to delamination of FHB hybrids, whilst they were able to better withstand impact damage than the other hybrids.