Toshio Araki

Modeling of Steel Weld Microstructure Using Monte Carlo and Finite Difference Hybrid Method

Monte Carlo (MC) and finite difference (FD) hybrid method is applied to numerically model the growth of austenite grains caused by welding thermal cycle in the heat affected zone (HAZ) of steel welds. The grain growth behaviors and pinning effects by dispersed particles are modeled by MC method while steep changes in temperatures with time and over space are by FD method. The connection of the two methods is made possible by correlating MC step to the real time through the grain growth theory. The model results are in a good agreement with experiments as well as previous experimental results published, and it is indicated that the developed model can be used to obtain a better understanding of the austenite grain structure development in HAZ and even to improve the grain refinement technology using dispersed particles.