A new method for identification of cyclic plasticity model parameters

Abstract

In this study, a new method for determining the material parameters of cyclic plasticity is presented. The method can be applied to evaluate the model parameters from any loading histories measured experimentally. The experimental data require basic processing only to be utilized. The method can be applied to calibrate the parameters of different elastoplastic models such as the Chaboche–Rousselier (Ch–R) constitutive equation or other model formulations which use different rules of isotropic hardening. The developed method was utilized to evaluate the material parameters of copper for a selected group of constitutive models. It is shown that among the considered model formulations a very good description of the mechanical properties of copper is achieved for the Ch–R model with two Voce terms used for simulating the isotropic hardening and two backstress variables utilized for capturing the kinematic hardening behavior. Furthermore, it is demonstrated that a model calibrated using the cyclic tension/compression data is able to properly capture the material response in torsion. Similarly, when the constitutive parameters are determined using the cyclic torsion data the model is able to properly reproduce the material behavior in tension/compression. It is concluded that for the considered type of constitutive equations the material parameters can be identified from a single mechanical test. The proposed methodology was validated using the relations derived analytically

Computational Methods of the Identification of Chaboche Isotropic-Kinematic Hardening Model Parameters Derived from the Cyclic Loading Tests

“…However, the numerical simulations of cyclic loading tests require the proper selection of material model which gives a multipurpose description of the material response. Over years, different models have been used in order to predict the cyclic response of materials, for example: bilinear [2], multilinear [3], Frederick-Armstrong (F-A) [4], Chaboche [5], Ohno-Wang [6], Abdel-Karim Ohno [7], Norton-Bailey [8] and Prager [9] models. The Chaboche model is often used in order to model the plasticity of different materials.…”

Estimation of cyclic hardening/softening and ratcheting response of materials through an algorithm to optimize parameters in Chaboche's hardening rule

“…The well‐known Chaboche's isotropic‐kinematic hardening (CIKH) model and its various modified versions to capture the non‐proportionality effects, large strain effects, temperature effects, and the loading rate dependency has been extensively used to examine the cyclic‐plastic response of different materials 46–57 . The calibration procedure associated with the determination of the parameters of the Chaboche's isotropic‐kinematic hardening (CIKH) model is typically based on trial and error approaches.…”

“…44,45 The well-known Chaboche's isotropic-kinematic hardening (CIKH) model and its various modified versions to capture the non-proportionality effects, large strain effects, temperature effects, and the loading rate dependency has been extensively used to examine the cyclic-plastic response of different materials. [46][47][48][49][50][51][52][53][54][55][56][57] The calibration procedure associated with the determination of the parameters of the Chaboche's isotropic-kinematic hardening (CIKH) model is typically based on trial and error approaches. The parameters of the CIKH model are initially estimated from the nature of the experimental cyclic stress-strain response, and are subsequently finetuned to have simulations which are in good agreement with the experimental observations on various material.…”