Abstract
The influence of test variables in fracture toughness test of glassfiber reinforced polycarbonate is studied by using DCB testpiece. The fracture toughness which shows the degree of difficulty of initial crack propagation, represents a constant value with a longer crack than a given length. The fracture toughness slightly increases with the increase of the tensile speed within the range of a Instron type testing machine and decreases with increase of the plate thickness. Moreover, the fracture toughness seems to be effected not by the plate width but by the restraint of rotation in the chucking systems.
