A CONSISTENT PENALTY METHOD FOR CONTACT BETWEEN A DEFORMING VISCOPLASTIC WORKPIECE AND A RIGID TOOL

A methodology is presented for enforcing a contact constraint between a viscoplastic workpiece and the tooling which deforms it, The algorit hm is based on a consistent penalty approach wherein an elemental disc retization permits elimination of contact tractions prior to-solution for the velocity field. When written in rate form, the new algorithm a llows contact constraints to be embedded in a viscoplastic formulation without altering the structure of the global matrix equation. Example s are presented to illustrate its use in metal forming simulations.