Meso-macro approach for composites forming simulation

Abstract

The F.E. analysis of woven composite reinforcement forming is an alternative to geometrical draping computation. It permits to account for mechanical behaviours of the fabric and static boundary conditions of the process. In this paper, macroscopic forming simulations of woven composite reinforcements are performed using finite elements composed of woven cells, the mechanical behaviour of which are computed by F.E. analyses at mesoscale i.e. on the unit cell of the fabric. The objective is to only calculate the relevant quantities in the woven finite element. The in-plane biaxiale tensile behaviour and the in-plane shear behaviour are obtained by 3D analyses of the woven cell submitted respectively to tension and shear. They need to take the specificities of the mechanical behaviour of the yarn (made of thousand of fibres) into account. Especially an objective derivative based on the fibre rotation is used. These computations on the unit woven cell have proved to be consistent with experimental tests. An example of deep drawing of a square box using the proposed approach is presented. Angles between warp and weft directions are computed as well as wrinkles.