3D inverse analysis model using semi-analytical differentiation for mechanical parameter estimation
Résumé
An inverse method is developed in order to estimate constitutive parameters of a material from compression tests. The direct model used to simulate mechanical tests is FORGE3®. It solves a transient thermo-mechanical problem using a finite element method. From velocity, pressure and temperature fields, any output of a mechanical test can be computed and compared with experimental data. A Gauss-Newton algorithm is implemented to solve the least-square problem associated with the inverse problem. The optimisation module is coupled with a semi-analytical sensitivity analysis method. This method is fast and stable when using a remeshing algorithm. A confidence interval estimator is proposed. The stability of the optimisation module and the confidence interval estimation are tested for numerical test cases. Finally, constitutive parameters of a steel grade are estimated for two elastic-viscoplastic constitutive laws.