Low-velocity impact behavior of intralayer hybrid composites based on carbon and glass non-crimp fabric

The low-velocity impact behavior of intralayer hybrid composite laminates made from warp-knitted fabrics with carbon (C) and glass (G) fibers was investigated. The impact testing at varying energy levels was performed using drop weight impact tests. The impact response was evaluated in terms of peak force and absorbed energy, and damage mechanism were characterized by visual observations and fluorescent dye penetration. Furthermore, the damage modes was assessed through quasi-static indentation (QSI) and acoustic emission (AE) techniques. The results from this study indicated that the hybrid structure exhibited a positive hybrid effect in peak force and the absorbed energy, and failure mechanism were significantly affected by the hybrid ratio and intralayer structure. The intralayer hybrid laminate of C:G = 1:1 revealed better impact resistance, and that of C:G = 1:4 exhibited less damage accompanied by the least carbon fiber content, however, more fiber damage appeared in C:G = 1:2 laminates.