Stress Characteristics of Nanocomposite Laminates with Effect of Nanoclay Content

Numerical stress analysis is performed by changing the nanoclay content of nanoclay/epoxy composite laminates from 0 to 9wt.% to 6 levels. The nanoclay effect on stress analysis of nanocomposite laminates, a finite element fomulation based on the higher-order theory and the classical contact law is investigated. Nano clay/epoxy composites consist of [0/45/0/-45/- 45/-45/0] 2S laminated sequences of 20 layers thick. Analysis results show that the elastic modulus of nano composite increases as the nano clay content increases from 0 to 7wt.%, so that the contact force between nano composite laminates and impactor increases, and the deflection of nano composite and contact duration decrease. And also, at the nano clay content9wt.%, the elastic modulus becomes rather smaller, resulting in the opposite phenomenon, which results in less the contact force and greater the deflection and the contact duration. The stress characteristics show that the principal stress σ1, σ2 and shear stress σ12 are the largest on the third, second, and first layers, respectively, from the top and bottom surfaces of nano composite laminates. Thus, it should be fully reflected in the initial design considering the largest principal stress σ1 among these.