Lecturer, University of Sydney, Sydney, N.S.W.
The use of surface-crack specimens subjected to tension and bending loads for the fracture toughness evaluation of two typical polymers, polypropylene and polystyrene, is described. Experimental results are discussed with particular reference to various correction factors such as slow growth, finite width, back face, crazing, and yielding. Fracture toughness values are also given for two grades of polystyrene of different molecular weights in the temperature range −160 to +40°C.
Paper ID: JTE10578J