3D contact modelling of large plastic deformation in powder forming processes

In this paper, the three-dimensional large frictional contact deformation of powder forming process is modeled using a node-to-surface contact algorithm based on the penalty and augmented-Lagrange approaches. The technique is applied by imposing the normal and tangential contact constraints and modifying the contact properties of frictional slip. The Coulomb friction law is employed to simulate the friction between the rigid punch and the work piece. It is shown that the augmented-Lagrange technique significantly improves imposing of the constraints on contact surfaces. In order to predict the non-uniform relative density and stress distributions during the large deformation of powder die-pressing, the nonlinear contact friction algorithm is employed within the framework of large finite element deformation, in which a double-surface cap plasticity model is used for highly nonlinear behavior of powder. Finally, the numerical schemes are examined for accuracy and efficiency in modeling of a set of powder components.