In a close collaboration with the Institute of Computational Physics at the Zurich University of applied Sciences, the possibilitys to simulate anisotropic materials in NMSeses where enhanced. NMSeses provides now fast simulation of anisotropic models with 3D shell elements and complex contact boundary conditions.

Anisotropic plastic deep-drawing of blisters

Modern laminates for the production of pharmaceutical blisters have a complex inner structure. Several layers of different plastic and aluminium sheets of thickness between 5 and100 µm are packed, stacked and glued together. When forming the blisters by deep-drawing, the overall functional role of the layers in the original laminate must be preserved: no holes, cracks or layer delamination is allowed after deformation.

From the numerical point of view, the major concern is the correct description of the anisotropic elasto-plastic behavior at large strains of the different materials. In general, it is non trivial task to fit these material parameters
due to these large number and strong interrelations.

The second figure right shows uniaxial stress-strain relations for an OPA specimen. Several strips have been cut at increasing angles of 45 degrees. One clearly observes a sharp transitions between elastic and plastic behavior, the orthotropic behavior and good fitting characteristics.