Multiscale approach dedicated to the relationship between tape laying singularities, thermomechanical damage and permeability of thermoplastic composites up to cryogenic temperatures – AMESDEP

AMESDEP proposes a multi-scale approach aimed at studying the impact of manufacturing-induced defects and draping singularities on the thermomechanical behaviour and permeability of thermoplastic composites used for liquid hydrogen storage. With the energy transition, these tanks are essential for vehicles requiring dense energy storage. However, the suppression of the liner in these tanks to reduce the mass makes controlling the permeability properties of the composites crucial. The project focuses on specific defects related to the Automated Fiber Placement (AFP) process, notably "gaps" and "overlaps," which can influence the mechanical properties and the formation of cracks in these materials. To the best of our knowledge, so far, few studies have explored the effect of these defects on permeability in cryogenic environments.
The project is structured into three work packages (WPs). The first WP focuses on analysing the defects induced by AFP process and their effect on the thermomechanical behaviour of thin and thick laminates. The second WP aims to evaluate the link between these defects and the permeability of the composites through experimental tests on flat and tubular samples containing calibrated singularities. The last WP seeks to improve the prediction of cracking scenarios through multi-scale modelling of the link between defects and damage mechanisms.
The innovative aspect of the project lies in considering the real defects introduced during the manufacturing process and studying their effects on permeability in cryogenic environments. The project will contribute to advancing knowledge on the relationship between the implementation of thermoplastic composites and their behaviour under extreme conditions, while providing recommendations for the manufacturing of cryogenic tanks with a challenging permeability requirement.