A mesoscopic model for deep drawing of carbon fibre prepregs at large strains

The simulation of prepregs must regard highly anisotropic, viscoelastic and thermal-chemical properties. In this work we split the constitutive equations for the two component material into an anisotropic elastic material part and an isotropic, viscoelastic behaviour part, where the former represents the fibres and the latter represents the matrix. The second part also takes account of curing, which is dependent on time and temperature. During real deep-drawing processes large deformations up to 50% are occurring, which is accounted for in a large strain theory. For the elastic fibres we use a Neo-Hooke law enhanced by an anisotropic part. For the viscoelastic matrix we use Hencky-strains (or logarithmic strains) and the work-conjugate Hill-stresses. Moreover the identified parameters for the model are presented. These are validated by simulation of a simple block and a real deep drawing process forming a spherical part.