FEM Simulation of Multiple Pass Radial Forging of Pyromet 718

Radial forging of a small diameter Pyromet 718 billet was modeled under nonisothermal and axisymmetric conditions using a finite element approach. In this model, each stroke of the radial forging tools was modeled as a separate simulation. An implicit method was developed to account for the non-contact time of the forging tools between each deformation cycle in order to improve transient temperature predictions during each pass. An improved representation of the chuckhead constraint was also developed. A three pass forging sequence using Pyromet 718 billet was conducted to validate the finite element model. Results show that deformation was generally uniform and penetrated to the workpiece center though surface strains tended to be higher. Temperature distributions show that significant differences develop between the workpiece surface and the interior and are maintained during forging. Comparison of the finite element predictions and the experimental measurements for effective strain and temperatures showed acceptable correlation. Superalloys 718,625,706 and Various Derivatives Edited by E.A. Loria The Minerals, Metals & Materials Society, 1994