A fast calibration approach of modified Chaboche hardening rule for low yield point steel, mild steel and high strength steels

Abstract

Chaboche model has gained prominent utilization in numerical simulation on cyclic behaviors of metal structure. However, the calibration of its material parameter may produce considerable cost. A simplified calibration way is of great importance to ease its application. To this end, a re-evaluation on chaboche model material parameters and simulated elastic-plastic laws was conducted regarding various steel grades. Futhermore, the characterisitcs of isotropic softening was coupled with the present model hardening rule. The kinematic rule was correlated with cumulative plastic strain. The modified model was then calibrated and validated base upon the coupon test result on 41 batches of steels, whose yield stress ranges from 100 MPa to 890 MPa. The calibrated material parameter were then correlated with corresponding monotonic mechanical properties. Accordingly, a simplified calibration procedure, based upon which the material parameters of modifed Chaboche model can be fastly estimated by yield strength and yield ratio, was constructed. As for low yield point steels, mild steels and high strength steels, this calibration method can ease the calibration of modified Chaboche model considerably.