Abstract
The solidification microstructure of the weld metal greatly affects the material properties. The process of solidification microstructure formation is closely related to the occurrence of solidification cracking. Therefore, it is important to predict the solidification microstructure of the weld metal. Since the solidification microstructure of the weld metal is affected not only by the microstructure formation associated with melting and solidification but also by the grain growth in the heat-affected zone, this study uses a Monte Carlo method to predict the formation of microstructure not only in the weld metal but also in the weld zone.
The aim of this study is to reproduce the microstructure of the weld zone, especially the solidification microstructure of the weld metal, for broad range of welding conditions that have not been investigated. The calculated weld bead shapes under each welding condition were in good agreement with the experimental results. The relationship between Monte Carlo step (MCS) and real time was clarified from the results of the experimental investigation of grain growth of SUS310S and the grain growth calculation by the Monte Carlo method. The microstructure morphology of the weld zone was reproduced by the Monte Carlo method. The calculated solidification microstructure of the weld metal was compared with the experimental results by EBSD analysis, and the calculated and experimental results were in good agreement. In conclusion, it was shown that the coupled prediction method developed in this study can predict the weld bead shape and the microstructure morphology of the weld zone, especially the solidification microstructure of the weld metal.
