A finite element model for the prediction of porosity in autoclave cured composites

Porosity represents a critical issue in composite manufacturing often leading to parts rejection. The aim of this work was to develop a multiphysic model capable to predict the conditions leading to porosity generated by water in composite parts processed by autoclave lamination. The developed model does not aim to assess the void growth phenomenon, as other models in the literature, but it enables the prediction of the thermodynamic conditions for water-generated porosity, where they could occur and how to prevent their presence by suitably modifying the process parameters. The potential of this multiphysic model was proved on epoxy matrix carbon fiber reinforced laminates cured after their exposition to a moist environment. The model was also applied to modify the curing cycle suggested by the prepreg provider in order to avoid favorable conditions for porosity development.