Finite element model for the simulation of preimpregnated woven fabric by deep-drawing and laying-up processes

Abstract : In order to use composite materials most effectively, it is necessary to determine their mechanical properties and physical behaviors under different loads. Structural composites are of interest due to their high strength/weight performance as compared to structural metals. A numerical model describing heterogeneous preimpregnated composite fabric deformations during the shaping process is composed of an association of two components (fibers and resin matrix), each of them exhibiting a specific mechanical behaviour. The warp and weft yarns composing the fabric are assimilated as a truss whose connecting points are hinged. The resin, which is considered as a membrane, kinematically is coupled to the fabric at these connecting points. Weft and warp fibres are modeled by truss finite elements. The viscous resin is modeled by 3D linear membrane finite elements (T3 or Q4). The formulation accounts for the large displacements and finite strains involved in the shaping process as well as the mechanical behaviour. Tensile tests of composite woven fabric are presented to validate the mesostructural behavior. Some numerical simulations of shaping processes by deep-drawing and laying-up processes are proposed and compared with the experimental results.