Akademik Veri Yönetim Sistemi
INDIAN JOURNAL OF ENGINEERING AND MATERIALS SCIENCES, cilt.17, sa.3, ss.186-198, 2010 (SCI-Expanded)
In this paper, the impact behaviour of glass/epoxy laminated composite plates with [0/+/-theta/90]s fiber orientation is investigated numerically at equal energy (40 J), equal velocity (2 m/s) and equal impactor mass (5 kg). In order to examine the stacking sequence effect, five different +/-theta fiber directions are chosen as 15 degrees, 30 degrees, 45 degrees, 60 degrees and 75 degrees. Three different plate thicknesses as 2.9 mm, 5.8 mm, and 8.7 mm are also selected to survey the thickness effect on impact behaviour of glass/epoxy composite plates. The overlapped delamination area is obtained for composite plates with different stacking sequences and different thicknesses. A transient finite element code 3DIMPACT is used for numerical analyses. In this code an eight-point brick element and the direct Gauss quadrature integration scheme are used through the clement thickness to account for the change in material properties from layer to layer. The Newmark scheme is also adopted to perform time integration step by step. In addition, a contact law incorporated with the Newton-Raphson method is applied to calculate the contact force during impact. Numerical results are compared with the experimental study and it has been seen that they are in good agreement with the experimental results.