Open Die Forging of Large Shafts with Defects – Physical and Numerical Modelling

Abstract:

The aim and scope of this paper is centered to analyze the influence of the geometry of V-shaped dies on the closure of internal centerline porosity defects in ingots during multistep open-die forging. The investigation is performed with small scale physical models made from lead using V-shaped dies with 90º and 120º and a reference pair of flat parallel platens. Holes drilled through the center of these preforms are produced to mimic centerline porosity in full scale cast ingots and intermediate rotation of the preforms replicate a multi-stage forging sequence under laboratory testing conditions. The presentation is supported by finite element modelling using an in-house developed computer program and the overall investigation shows that better results in closure of centerline defects are obtained with a V-shaped die with 120º die angle.

• Periodical: Key Engineering Materials (Volumes 554-557)
• Pages: 2145-2155
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.554-557.2145
• Online since: June 2013
• Authors: Peter Christiansen, Jesper Hattel, Nils Bay, Luis Alves, Paulo A.F. Martins
• Keywords: Centerline Porosity, Experimentation, Finite Element Modeling (FEM), Open Die Forging, V-Shaped Dies

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