Thermoviscoelastic anisotropic analysis of process induced residual stresses and dimensional stability in real polymer matrix composite components

A design tool able to predict the residual stress state and dimensional stability of large complex shaped composite parts has been developed. It is based on a finite element model, using a three-dimensional anisotropic thermo-viscoelastic formulation. Asymmetric cross-ply laminates were manufactured in a ‘V-shape’ from non-crimp carbon fibre fabric reinforced epoxy for validation. A hybrid finite element mesh, containing both shell and solid elements was proposed as the solution to minimising the computational resources required. Results demonstrate that the approach is valid, that the effect of cooling rate on the predicted dimensional stability is significant but that the model over-predicts the experimentally observed part deformation.