INFLUENCE OF THE BILLET GEOMETRIC SHAPE ON THE PROCESS OF HOT BACKWARD EXTRUSION OF HOLLOW PRODUCTS FROM HIGH-CARBON STEEL

Abstract

Mathematical models were developed using the finite element method to investigate the hot reverse extrusion of high-carbon steel hollow products from round and square billets. A plastic metal model was employed. The deformation rates were determined to maintain the required thermal conditions for hot deformation throughout the forming process. For both billet shapes, the relationships between extrusion force and punch displacement were established, along with the distribution of specific forces on the contact surfaces between the deformed billets and the tooling. The distribution of temperature, stress components, and strains for the final stages of extrusion are presented. The refinement of the metal structure through plastic deformation was evaluated based on train intensity distributions. The final shapes and dimensions of the products were identified. A comparative analysis of the simulation results for the extrusion processes was performed.