Numerical analysis of the crack paths produced by fibre–matrix interface failure in cross-ply LFRP laminates

Abstract

The so-called matrix failure, also named inter-fibre failure, is one of the main failure mechanisms in long fibre reinforced polymers (LFRPs). This mechanism is characterized by the debonding of some fibres when transverse loads are diving the failure process. In the present study, the prediction of cracks initiation and growth within fibre–matrix interfaces of the 90° layer in [0,90n]s laminates is aimed. To this end, the behaviour of the fibre–matrix interface is characterized using a Linear Elastic Brittle Interface Model (LEBIM) that has been implemented in the commercial FEA code Abaqus ® and applying a solution algorithm built in Python called the Sequentially Linear Analysis (SLA). The results point out the capability of the debonding process to represent the generation of transverse cracks, showing how the onset and growth of interface cracks within a laminate are influenced by different factors such as the local distribution of fibres, the value of the fibre–matrix interfacial fracture properties and the thickness of the 90° layer.