Micro-mechanistic analysis of in situ crack growth in toughened carbon/epoxy laminates to develop micro-mechanical fracture models

Abstract

Mode I and Mode II crack growth through particle-toughened CFRPs (Carbon Fibre Reinforced Plastics) have been captured using in situ and ex situ Synchrotron Radiation Computed Tomography (SRCT) and Synchrotron Radiation Computed Laminography (SRCL). These experiments were used to provide non-destructive identification of fracture mechanisms at representative stress states for two different material geometries. The local micro-structure prior to crack propagation, the location of particle/matrix de-bonding events, the formation of bridging ligaments, and the evolution of the resultant crack path was identified and related to the local micro-structure. Such data is invaluable to the development and validation of physically representative micro-mechanical models for these material systems that are increasingly being used in primary aerospace structures