Thermo‐viscoplastic parameter identification formulated as an inverse finite element analysis of the hot torsion test

This paper deals with an inverse finite element approach applied to the analysis of the steel behaviour during a hot torsion test. The rheological test is simulated by a finite element model and the inverse analysis principle is to find the constitutive parameters which permit to compute the closest values of a set of experimental torques which are measured for different operating conditions. A least square deviation between computed and measured variables is minimized with respect to the Theological coefficients corresponding to an appropriate material constitutive equation. A numerical validation of the proposed method is illustrated in the case of a Norton‐Hoff thermo‐viscoplastic law. All the rheological parameters which defined the consistency and the strain rate sensitivity can be simultaneously determined for a chosen analytical expression.