• Experimental friction test (Bushhausen /Altan -Ohio State University - 1992).
• Mean friction coefficient is deduced from the comparison of experimental and numerical (FEM) “cup height ratios” h1/h2 ( =1 if frictionless).
• Frictional conditions close to the forging process:
  • Interface pressure ~ 2500MPa.
  • Surface temperature ~600°C.
  • Surface enlargement ~3000%.
• Typical numerical simulation needs remeshing.

Comparison with FE results obtained using Deform2D (and remeshing).