A three-dimensional frontal cellular automaton model for simulation of microstructure evolution—initial microstructure module

Abstract

This paper presents a three-dimensional frontal cellular automaton (FCA)based model for modelling of microstructure evolution during technological processes. It is a hierarchical system. The first level is the FCAs, the second level contains modules of microstructural phenomena and the third level is presented by the models of technological processes. The module of the initial microstructure (IM) is one of the components of the second level. The IM allows one to obtain a digital material representation of given parameters, which can be used by other modules for further simulation. The parameters that must be assured by the IM module are the following: shape of the grains and distributions of the grain size, crystallographic orientation and boundary disorientation angles.To obtain the required parameters, the FCAs are first used as a tool for the creation of the basic microstructure characterized by the shape of the grains. The grain size distribution is obtained by the method, which changes nucleation and grain growth conditions. After the creation of the microstructure, crystallographic parameters are established. Distribution of the crystallographic orientation and boundary disorientation angles can be obtained independently or as associated parameters. Some examples of microstructures obtained by the IM module are presented in this paper.

Modeling with FCA-Based Model of Microstructure Evolution of MgCa08 Alloy During Drawing of Thin Wire in Heated Die / Modelowanie Za Pomocą FCA Rozwoju Mikrostruktury Stopu MgCa08 Podczas Ciągnienia Cienkiego Drutu W Podgrzewanym Ciagadle

“…Inside the grains, a creation of new dislocation cells is modeled. As it was demonstrated in [31,32], dislocation cells appear at the beginning stage of severe plastic deformation. Then the dislocation cells evolves in subgrains and new grains.…”

“…Initial microstructure for simulation was created according to conditions and principles described in [31]. …”

“…Description of some modules of the system can be found in previous publication: initial microstructure [31], crystallization [14], recrystallization [19,21], phase transformation [23] and grain refinement [27]. Results of modelling and simulation with this FCA-based system are presented elsewhere: solidification in continuous casting [14], hot flat and shape rolling [21,30], the roll-bonding process and MAXStrain technology [27,32], powder bed generation [33], etc.…”

Three-dimensional frontal cellular automata modeling of the grain refinement during severe plastic deformation of microalloyed steel

“…Then, the specimen after each cycle is back to its initial size, but the material accumulates strain. Some results of the computer simulation of two cycles MaxStrain deformation are presented in [33,39]. The first publication [33] considers an appearance of new boundaries only, without evolution of boundary disorientation.…”

“…The first publication [33] considers an appearance of new boundaries only, without evolution of boundary disorientation. The second publication [39] considers the module of the initial microstructure taking into account the grain refinement. The initial microstructure was obtained in three stages: modeling the initial coarse microstructure -(a), the grain refinement according to required grain (subgrain) size distribution -(b) and fitting the disorientation boundary angle to the required distribution -(c).…”