CRACK TIP DEFORMATION OF PP-MATERIALS

摘要

To get information about the deformation processes at the crack tip, in situ measurements were done using a miniaturized bending device and a stereomicroscope. The influence of ethylene content and elastomer content on the crack opening displacement at crack initiation point is demonstrated on different poly-propylene (PP) materials: random copolymers, blends and heterophasic copolymers. Crack resistance curves can be achieved from results of the in situ measurements. This shows, that the used experiments are suitable as a single specimen method.