Influence of Ply Stacking Sequences on the Impact Response of Carbon Fibre Reinforced Polymer Composite Laminates

In recent years, there has been a growing demand for high strength-to-weight ratio and lightweight structures in several applications, such as wind energy, automotive, aerospace, telecommunication and construction industries. Carbon fibre reinforced polymeric (CFRP) composite is one of the promising materials with aforementioned inherent properties and applications. These properties vary with different techniques of their manufacturing, such as stacking sequence. Hence, it is germane and important to conduct an extensive study to investigate the effect of stacking sequences on the properties of CFRP composites. Consequently, this paper experimentally investigated the influence of different ply stacking sequences on quasi-static low-velocity impact behaviour of approximately 150 x 130 x 2 mm CFR epoxy composite laminates, manufactured by hand lay-up technique. Five different stacking sequences, denoted as samples A, B, C, E and F were tested under impact loads of 2.00, 2.25 and 2.50 kN. The results showed that the Sample A with stacking sequence of [90/±45/0]s exhibited the highest impact resistance under a maximum load of 2.50 kN before it finally fractured at a maximum displacement of nearly 10.20 mm, prior to an inter-ply delamination occurrence at displacement of approximately 5.50 mm. Similarly stacked sample B recorded the lowest inter-ply delamination damage, while sample C exhibited highest delamination damage. Both samples E and F exhibited similar impact properties. Moreover, samples A, B and C absorbed impact energies of 17.50, 6.25 and 14.13 J, respectively. Conclusively, sample A with highest impact resistance and absorbed energy is hereby recommended, been a promising material for engineering application within the test conditions and parameters, especially under a low-velocity impact load.