Influence of Stacking Sequence and Nanoclay Content on Macroscopic Behaviour of Nanoclay/Epoxy Composites

A refined impact finite element approach in conjunction with the Reddy's higher-order shear deformation theory and Hertz's contact law is applied to study the influence of stacking sequence and nanoclay content on impact response of nanoclay/epoxy nanocomposite of 20 layers and 5 mm thickness. Combinations of four typical stacking sequences and six nanoclay contents inside epoxy, namely, the stacking sequences [020], [9020], [0/45/0/-45/0]2S, [90/45/90/-45/90]2S, and nanoclay contents 0, 1, 3, 5, 7, 9wt.% at [0/45/0/-45/0]2S are considered. The results of this analysis for four stacking sequences show that the unidirectional layup ([0/45/0/-45/0]2S and [90/45/90/-45/90]2S) and cross-ply layup ([020] and [9020]) in this nanocomposite plate indicate, the same impact response, respectively. In addition, from results of nanoclay contents 0, 1, 3, 5, 7 and 9 wt. % at [0/45/0/-45/0]2S, it can be seen that the greater the rigidity of between 0 to 7wt. %, the greater the contact force and the smaller the deflection, the smaller the COR becomes. However, at 9wt. %, the rigidity is reduced, causing the opposite effect of all impact responses.