Development and verification of a finite element model for double diaphragm preforming of unidirectional carbon fiber prepreg

A finite element (FE) model for double diaphragm preforming of a unidirectional (UD) carbon fiber prepreg was developed. In the model, a hyperelastic constitutive model considering the effect of temperature was used to describe the nonlinear large deformation behavior of the diaphragm in the preforming process. The prepreg lamina was characterized by a transverse isotropy elastic model. The interfacial behavior between prepreg laminate was characterized by a previously developed analytical three-stage inter-ply slipping model which considers the effects of preforming temperature and pressure. Double diaphragm preforming experiments of the UD carbon fiber prepreg laminates over a C-type mold were implemented and then simulated by using the proposed FE model. Comparisons between experimental results and simulation data verified the numerical model. The proposed FE model provides a numerical tool for processing simulation and optimization for double diaphragm preforming of prepregs.