1 INTRODUCTION The work is focused on development of the model, which allows connection between phenomena occurring in materials in various scales. Multiscale CAFE approach, which combines cellular automata (CA) and finite element (FE) methods, is used. In this approach FE method describes material in the macro scale, while CA method simulates micro and mezo scale phenomena. In consequence, the models operating at different scales contribute to the local evolution of microstructure. Earlier research proved qualitatively exceptional predictive capabilities of the CAFE method in modelling strain localization [1] and dynamic recrystallization (DRX) [2]. In this paper, the effort was made to improve the transition rules, which were developed in [2], and which describe the state of the material at the micro scale. The second aim of the study is to assess the capabilities of the model in qualitative prediction of microstructure development during DRX. It was done by comparison of the CAFE model predictions with the experimental data for hot rolling in the laboratory mill. 2 MODEL 2.1 Finite element solution The FE program developed by the authors and based on rigid-plastic thermomechanical solution is used. Details of the model are given in [3] and are not repeated here. Flow stress is the material parameter in this model and can be calculated by the CA model. 2.2 CAFE model The CA model accounts for the evolution of microstructure and dislocation density. The 2D CA lattice with neighbourhood described in [2] and with periodic boundary conditions is used. The lattice of cells represents the image of microstructure and reproduces topological relations between grains. The state of each cell is described by four state variables: 1) local dislocation density ρ, 2) orientation φ, 3) distance variable x that controls migration of GB, 4) assignment to a grain. The grains in the model are represented by instances of Distant Neighbourhoods ABSTRACT: The paper is focused on development of multi-scale CAFE approach, which combines cellular automata (CA) and finite element (FE) methods. The CA model of dynamic recrystallization (DRX) was implemented into the thermal-mechanical FE code, which simulates rolling process using steady state Eulerian approach. Several CA spaces were created at the cross section of the sample and their state was calculated using changes of the external variables along the flow lines. Current local values of temperature, strain, strain rate and stress are calculated by the macro-scale FE model and then passed to micro-scale CA simulations. Improvements in analysing of average grain size in CA simulation were introduced. The CAFE calculations were performed for hot rolling of the carbon-manganese steel. The resulting grain sizes after the process were compared with the experimental data, achieving satisfactory consistency. Key words: Dynamic recrystallization, Hot rolling, Multiscale model, Cellular automata, CAFE Multiscale model of dynamic recrystallization in hot rolling J. Gawad 1 , W. Madej 1 , R. Kuziak 2 , M. Pietrzyk 1 1 Akademia Gorniczo-Hutnicza, al. Mickiewicza 30, 30-059 Krakow, Poland URL: www.isim.agh.edu.pl e-mail: jgawad@metal.agh.edu.pl; madej@metal.agh.edu.pl; pietrzyk@metal.agh.edu.pl 2 Instytut Metalurgii Zelaza, ul. K. Miarki 12-14, 44-100 Gliwice, Poland URL: www.imz.gliwice.pl e-mail: Kuziak.R@imz.gliwice.pl