Abstract
Fracture energy and crack length of AS composites with plane oriented planar reinforcements (glass flake, mica) were investigated by falling ball impact test. The results were compared with those of glass fiber and glass bead filled AS. The main results obtained are as follows : 1) The fracture energy of glass flake composites is higher than that of glass fiber and glass bead composites with equal diameter of the reinforcements. The higher fracture energy of the flake composite is considered to be due to the two dimensional reinforcing effect of flakes. 2) The energy required to increase the length of cracks was measured and the results were compared with the Kelly's equation (fiber composite) and the modified Kelly's equation (flake composite) assuming the falling ball energy is absorbed by the pull out of reinforcements from the matrix. Good agreements were obtained between the experimental data and the theoretical predictions.
