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).