Autoclave manufacturing of thick composites

The autoclave manufacturing of thick laminates is addressed by modeling the heat transport phenomena occurring through the composite, the bagging and the tooling system. A new methodology for the evaluation of the energy transfer regimes is proposed accounting for the heat fluxes from the bag and the tool side, the temperature through-the-thickness gradients and the heat generated by the resin cure reaction. The proposed approach enables the prediction of the temperature history of the autoclave assembly without knowledge of the effective thermal inertia of the two external layers, which could be difficult to evaluate owing to possible deformations of the bag during the manufacturing cycle and nonuniform shape of the metallic tool along the part. Experimental data from industrial autoclave runs have been collected and analyzed to validate the method.