Determination and analysis of the constitutive parameters of temperature-dependent dislocation-density-based crystal plasticity models

Determination and analysis of the constitutive parameters of temperature-dependent dislocation-density-based crystal plasticity models

Sedighiani, K. (TU Delft Team Jilt Sietsma; Max-Planck-Institut für Eisenforschung)
Traka, K. (TU Delft Team Maria Santofimia Navarro; Max-Planck-Institut für Eisenforschung)
Roters, Franz (Max-Planck-Institut für Eisenforschung)
Raabe, Dierk (Max-Planck-Institut für Eisenforschung)
Sietsma, J. (TU Delft Team Jilt Sietsma)
Diehl, Martin (Max-Planck-Institut für Eisenforschung; Katholieke Universiteit Leuven)

2022

Physics-based crystal plasticity models rely on certain statistical assumptions about the collective behavior of dislocation populations on one slip system and their interactions with the dislocations on the other slip systems. One main advantage of using such physics-based constitutive dislocation models in crystal plasticity kinematic frameworks is their suitability for predicting the mechanical behavior of polycrystals over a wide range of deformation temperatures and strain rates with the same physics-based parameter set. In this study, the ability of a widely used temperature-dependent dislocation-density-based crystal plasticity formulation to reproduce experimental results, with a main focus on the yield stress behavior, is investigated. First, the material parameters are identified from experimental macroscopic stress–strain curves using a computationally efficient optimization methodology that uses a genetic algorithm along with the response surface methodology. For this purpose, a systematic set of compression tests on interstitial free (IF) steel samples is performed at various temperatures and strain rates. Next, the influence of the individual parameters on the observed behavior is analyzed. Based on mutual interactions between various parameters, the ability to find a unique parameter set is discussed. This allows identifying shortcomings of the constitutive law and sketch ideas for possible improvements. Particular attention is directed toward identifying possibly redundant material parameters, narrowing the acceptable range of material parameters based on physical criteria, and modifying the crystal plasticity formulation numerically for high-temperature use.

Compression test
Crystal plasticity
Dislocation density
IF Steel
Parameter identification

http://resolver.tudelft.nl/uuid:c6ecdab4-da25-4dc8-9ad8-9e33445f7dbe

https://doi.org/10.1016/j.mechmat.2021.104117

0167-6636

Mechanics of Materials, 164

Institutional Repository

journal article

© 2022 K. Sedighiani, K. Traka, Franz Roters, Dierk Raabe, J. Sietsma, Martin Diehl