Monte Carlo simulation of grain boundary pinning in the weld heat-affected zone

A methodology for obtaining a one-to-one correlation between Monte Carlo (MC) and real parameters of grain size and time is described. Using the methodology, and the MC grain growth algorithm, the grain structure in the weld heat-affected zone (HAZ) of a 0.5 Mo-Cr-V steel has been simulated. The simulations clearly show that the kinetics of grain growth can be retarded by the presence of steep temperature gradients in the weld HAZ. Additional pinning due to the formation of grain boundary liquid near the solidus temperature has also been simulated. It is shown that in order to accurately predict the observed grain size in the weld HAZ of the 0.5Cr-Mo-V steel, the retardation in growth kinetics due to temperature gradients as well as liquid pinning should be considered.