On the calibration of the Chaboche hardening model and a modified hardening rule for uniaxial ratcheting prediction

A systematic mathematical approach is developed in the context of uniaxial cyclic ratcheting for the parameter determination of the decomposed Chaboche hardening rule. This is achieved by deriving the relation between the evolution of the backstress and the plastic strain accumulation. Unlike current calibration techniques where a trial-error approach is employed to fit the simulation results to experimental data, the proposed method determines the parameters directly from uniaxial ratcheting experiments. Numerical results indicate that Chaboche's hardening model is much more efficient than what has been demonstrated before. Finally, as an improvement to the decomposed model, a modification is made to one of the backstress components. This improved component enables the model to predict uniaxial ratcheting with more accuracy. (C) 2009 Elsevier Ltd. All rights reserved.