Final work : Impact Damage Modelling on Composite Structures

Abstract

The advanced properties of carbon fiber reinforced composite materials, such as their low strength and stiffness-weight ratios, make them a very attractive alternative for aerospace applications, particularly for fan-blade design. However, their integration is truncated due to its susceptibility to impact phenomena, and the lack of reliable numerical models that capable to predict their damage response. Aircraft components, particularly fan blades, are known to experience harmful foreign impact events e.g. tool-drop, ice ingestion, bird strike, etc. The aim of this project is to provide the necessary theoretical background on the failure mechanisms experienced by a composite during an impact, and to build Foreign Object Impact (FOI) model on a rectangular composite plate for the cases of low and high velocity. The focus of the high velocity model is to validate the ballistic response of a composite rectangular plate by means of experimental and numerical results found in the literature [1, 4], and to analyze the main sources of damage present and the influence of relevant physical properties i.e. thickness, stackup sequence, etc. On the other hand, the low velocity model is focused in delamination modelling. Two different sub-models are developed in this case: (1) ”Elastic Model”, in which only interlaminar damage between the plies is modelled and, (2) ”Failure Model”, where both intra and interlaminar failure are considered. The final goal is to provide an organized numerical methodology to model an impact on a composite structure and to analyze the effect of the projectile velocity on the damage mechanism developed by the composite target.