Damage and failure modelling of composite materials for the automotive industry

Abstract

Fibre-reinforced polymer-based composite materials fail due to a wide variety of interacting damage mechanisms, which require complex constitutive models in order to develop Finite Element (FE) predictive analysis. In the design of automotive components, the whole body of the vehicle is needed to be modelled for certain simulations. This makes necessary a computationally-efficient constitutive model in order to get a proper definition of its behaviour. In this master thesis, the model published by Mart´ın-Santos et al. in 2013 is taken as a reference, in order to take advantadge of the simplified loading functions and the reduced mesh influence in the results due to the implementation of the Crack Band Methodology. In this work, the model is upgraded to be able to reproduce the behaviour of a wider range of materials than the original model, and to become more stable in simulations regarding extreme loading conditions, as the crushing of the composite due to an axial impact event. The proposed constitutive model is implemented in Pam-Crash FE code, in order to take advantage of its well-proved experience in explicit analysis of specimens under dynamic loads in the automotive industry. The implementation is validated by comparing the results of FE predictions with experimental data from delamination and low-velocity impact tests. A good correlation between the numerical and experimental results is achieved when using a bilinear cohesive law, for the different models.