Three dimensional Monte Carlo simulation of grain growth during GTA welding of titanium

The work reported here represents significant advancement in the modeling o f grain structure evolution in metallic systems. Utilizing computed tempera ture fields from a well tested heat transfer and fluid flow model, the evol ution of grain structure was simulated for the first time using a three dim ensional (3D) Monte Carlo model of grain growth in the heat affected zone o f commercially pure titanium welds. The computed weld geometry and the simu lated mean prior beta grain size for different heat inputs;agreed well with the corresponding experimental results when turbulence in the weld pool wa s considered. The grain sizes at Various locations equidistant from the fus ion line were different, indicating that the results of previous 2D calcula tions need to be reexamined. The computed grain size distribution agreed we ll with the corresponding experimental data. The agreement indicates signif icant promise for understanding grain growth in the entire heat-affected zo ne using a comprehensive phenomenological model. (C) 2000 Acta Metallurgica Inc. Published by Elsevier Science Ltd. AII rights reserved.