Simulaition and analysis of process-induced distortions for composite structures

Process-induced distortions (PID) of fiber-reinforced polymer matrix composites bring many problems to parts assembly. A multi-level simulation method for cure process of composite integrated structure was developed to simplify calculation and improve accuracy of prediction. Panels and stiffened panels were manufactured by autoclave process to verify the simulation method. It is found that numerical predictions compared quite well with experimental measurements. Furthermore, PID investigations were carried out for thermoplastic composites produced by thermoforming process. Both process features and material characters were incorporated in simulation. Concerning hemispheres with symmetric lay-ups, stamping induced stresses play a dominant role in PID and determine the deformation trend; fiber reorientations have an important effect on the thermally induced deformations.