FINITE-ELEMENT SIMULATIONS OF TEXTILE COMPOSITE FORMING INCLUDING THEBIAXIAL FABRIC BEHAVIOR

A finite element simulation of fibre fabric shaping process is propose d. The behaviour of fabrics is experimentally studied from biaxial ten sile tests. on cross shaped specimens. These experiments permit to inv estigate the influence on the fabric behaviour of the undulation varia tions of the weaving and of the interactions between warp and weft yar ns. A constitutive model including these aspects is proposed, validate d and identified from the biaxial tests. Finite elements made of woven yarns are built in the field of non-linear kinematics. The deformatio n energy is calculated as the sum of the energy of each elementary cel l for which the biaxial behaviour previously identified is considered. A drawing simulation with square punch and die is presented. It allow s to distinguish the geometries of the tools which are possible or not for the shaping process. The influence of the undulation Variations a re studied in a second example. (C) 1997 Elsevier Science Limited.