Abstract
Owing to remarkable properties, composite materials are generally used in varieties of industries especially for high value products. Laminated composites are commonly used which are composed of several prepreg plies. This kind of structure has an advantage of tailoring material properties easily by changing the way of lamination. But the trade-off is that delamination tends to occur between plies. There is a difference on degree of drilling-induced delamination between planar structure and tubular structure. In general, the magnitude of thrust force is the most determining factor on drilling-induced delamination. If one can obtain the critical thrust force beyond which fracture occurs, it is possible to predict the onset of delamination. In view of this, a finite element simulation is conducted to determine the value of critical thrust force for each structure. It is found that the critical thrust force of tubular structure is slightly lower than that of planar structure. After that, experiments are made to examine the accuracy and applicability of the simulations .The values obtained from simulation and experiment are very close. As a result, it is verified that critical thrust force determined by simulation is feasible.