Application of the instrumented impact test to the toughness characterization of high impact thermoplastics

The toughness behaviour of some blends and a PA/CF composite under dynamical loading (1 m/s) based on the J-integral was studied. Different methods were used for the tests. It can be shown that the multiple specimen stop-block technique gives the most conservative results. Furthermore the influence of specimen thickness on crack resistance behaviour was studied. The instrumented Charpy impact test enables the determination of valid crack resistance curves on plastics with small specimen geometries. The advantages and disadvantages of using the known standards for metallic materials in comparison to the ESIS TC4 testing protocol were discussed and a physical concept is compared with the empirical description of R-curve behaviour with the standards.