A plane strain model for process-induced deformation of laminated composite structures

We present a plane strain finite element model for simulation of the develo pment of process-induced deformation during autoclave processing of complex -shaped composite structures. A "cure-hardening, instantaneously linear ela stic" constitutive model is employed to represent the mechanical behaviour of the composite matrix resin, and micromechanics models are used to determ ine composite ply mechanical properties and behaviour, including thermal ex pansion and cure-shrinkage. Structures with multiple composite and non-comp osite components can be simulated through the use of such strategies as ada ptive time-stepping and incorporation of multiple composite plies into each finite element. The effect of process tooling can also be directly modelle d through simulation of tool/part interfaces and post-processing tool remov al. Integration of the residual deformation model with models for heat tran sfer and resin cure and resin flow permits analysis of all major identified sources of process-induced deformation during the autoclave process. Model application is demonstrated through prediction of process-induced deformat ion of a number of variations of a simple L-shaped laminate. The model is s hown to provide accurate predictions of both spring-back angle and warped s hape of the final part.