Hot extrusion process modeling using a coupled upper bound-finite element method

• A new stream function-upper bound solution is proposed.
• The model can be used under isothermal and non-isothermal conditions.
• Comparison between predictions and experiments verifies the model results.

A thermo-mechanical model has been developed for modeling of hot extrusion processes. Accordingly, an admissible velocity field was first proposed by means of stream function method and then, extrusion pressure as well as temperature variations within the metal and the die were predicted employing a combined upper bound and Petrov–Galerkin finite element analysis. In order to evaluate the model predictions, hot extrusion of AA6061-10%SiCp was considered under both isothermal and non-isothermal conditions and the predicted force–displacement diagrams under various extrusion conditions were compared with the experimental ones and reasonable consistency was found between the two sets of results.