Numerical modelling of thermomechanical processes related to bulk forming operations

Abstract

A thermomechanically sound, decoupled model, numerically unified for cold and hot bulk metal forming is cast into a finite element formulations. The mechanical module is based on elasto(visco)plastic material costitutive laws and general interface frictional contact conditions with the assumption of rigid tools. Introduction of a logarithmic strain based finite strain model in the contex of a geometrically nonlinear assumed strain method characterizes the numerical treatment of incompressibility at large deformations. A non-associated slip rule is employed in the contex of the plasticity theory of friction, with nonlinear master segment geometry describing the contact kinematics. Consistent linearisation in all aspects of algorithmic development provides robust and quadratically convergent soltutions. This is shown in 2-D plane strain and axisymmetric numerical examples, where simulations of both cold and hot bulk metal forming processes are performed