Accelerated cyclic plasticity models for FEM analysis of steelmaking components under thermal loads

摘要

Steelmaking components are often subjected to thermo-mechanical loads applied cyclically. In this case the choice of a suitable cyclic plastic model to be used in the numerical simulation is a crucial aspect in design. Combined (kinematic and isotropic) model permits the cyclic material behavior to be captured accurately. On the other hand, such model often requires unfeasible computational time to arrive at complete material stabilization. Simplified or accelerated models have then been proposed to make simulation faster. In this work, the thermo-mechanical analysis of a round mold for continuous casting is addressed as a case study. Due to axi-symmetry, a plane model can be adopted. This permits a finite element (FE) analysis with a combined model to be performed until complete stabilization. A comparison with other models able to speed up the simulation (accelerated models with increased values of saturation speed, Prager and stabilized models) was performed. It was found that only accelerated models give equivalent strain range values that do not significantly differ from the (reference) combined model, independently from the speed of saturation adopted.