THE EFFECT OF MATERIAL MODELS IN THE FEM SIMULATION ON THE SPRINGBACK PREDICTION OF THE TRIP STEEL

In this work, the influence of material models used in the FEM simulation on the springback prediction is investigated. The interest of this paper is to extend the knowledge base regarding springback predictions in numerical simulation. The springback effect of a V-shaped sheet metal part made of TRIP steel, with a thickness of 0.75 mm was investigated. The bending angle was set to 90°.  In the numerical simulation, Hill48 and Barlat yield criteria were used in combination with Ludwik's and Swift's hardening models. Achieved data from the numerical simulations were compared and evaluated with experimental test results. The experimental results showed the relation between springback and calibration force. The effect of specimen cut direction on the springback was smaller in comparison with the calibration force. The numerical results of the springback were not identical with the experimentally achieved springback values in most cases. Particularly, when a calibration force of 1 800 N was used in the simulation. The simulation results showed a good correlation between experimental and numerical results, when Hill48 and Barlat yield criteria were used in combination with Ludwik hardening law and calibration force F with the value 900 N was applied.