Cellular automata full-field numerical simulation of static recrystallization based on 3D EBSD data of highly deformed two-phase microstructure

The concept of the Digital Material Representation (DMR) was proposed a few years ago and is constantly evolving as it is often used in the Integrated Computational Materials Engineering (ICME) approach both in 2D and 3D analysis of materials processing. However, when DMR models of complex microstructures are considered, limitation to 2D computational space may influence the quality of numerical predictions, far more than in the case of simple mean-field models. Such 2D DMR models, by definition, cannot predict the influence of geometrical heterogeneities in the third dimension, which are of importance when microstructure evolution of highly deformed heterogeneous microstructures are investigated. Therefore, the main goal of this research is to prepare a reliable 3D DMR model for further Cellular Automata (CA) full-field calculations of static recrystallization based on a series of 2D images from SEM/EBSD serial sectioning data. Application of a serial sectioning procedure for imaging large 3D microstructure volume is not often used, as it is usually based on time-consuming and very precise manual labour. However, at the same time, such an approach provides a significant amount of information about microstructure morphology and texture that could be used as input data for microscale discrete modelling approaches. Within the work series of 2D SEM/SE2, images of a two-phase microstructure were accompanied by an EBSD investigation to clearly identify the morphology of both constituents. Then, a dedicated 3D reconstruction algorithm supported by machine learning solutions was developed and used to recreate complete volumetric information about investigated highly deformed microstructure. Eventually, such 3D input data are used to simulate 3D grain growth during static recrystallization with respect to the heterogeneities in the stored energy, crystallographic orientation and grain boundary curvature.