The Thermomechanical Behaviour of Carbon Fibre Reinforced Polymer in a Fire
conference contributionposted on 2020-12-07, 16:29 authored by Timothy Aspinall
The effect of fire on military aircraft is a large factor in assessing their survivability and understanding this is a complex and challenging task, which requires specialist research. Quantifying the thermomechanical behaviour of Carbon Fibre Reinforced Polymers (CFRP) used in aircraft structural components is an essential required step to determine their structural integrity when exposed to fire. The thermomechanical response leading to the loss of mechanical properties is governed by the glass transition, thermal decomposition (pyrolysis) of the resin matrix and oxidation of the carbon fibre reinforcement. These phenomena are strongly coupled and their effect on the mechanical response of CFRP are poorly documented in the literature.
This work presents the development of a low-cost method for investigating the thermomechanical properties of such materials in terms of displacement and failure time under constant load. The work has centred on, an experimental study which is designed to quantify the thermomechanical behaviour of CFRP during three-point bending under different thermal exposures. Of particular interest was the contribution to the failure mechanism of the propagation of the glass transition isotherm through the sample and fibre oxidation on the exposed surface of the samples. Consequently, the results can be used to assess the understanding of failure modes of CFRP in loadbearing structural components of military aircraft.