Three-dimensional monte carlo simulation of grain growth in the heat-affected zone of a 2.25Cr-1Mo steel weld

Abstract

We report here the first three-dimensional (3-D) Monte Carlo (MC) modeling of grain growth in the heat-affected zone (HAZ) of a weldment. Computed grain-size distributions in the HAZ of a 2.25Cr-1Mo steel, for different heat inputs in the range from 1.1 to 4.8 MJ/m, were compared to independent experimental results. The simulated mean grain size for different heat inputs agreed well with the corresponding independent experimental data. The mean grain size at various locations equidistant from the fusion line were different. The predicted grain size from the 3-D model matched the experimental results more closely than that from a two-dimensional (2-D) model. When the whole calculation domain was subjected to a single thermal cycle experienced by a monitoring location within the HAZ, the computed grain size was larger than that calculated at the monitoring location by taking into account the prevailing temperature gradient due to thermal pinning. The good agreement between the simulated grain structure and the corresponding experimental results indicates significant promise for understanding grain-growth phenomena in the entire HAZ by using the MC technique.

Existence or nonexistence of thermal pinning effect in grain growth under temperature gradient

“…Some Monte Carlo simulations on the grain growth in the HAZ demonstrated the existence of the thermal pinning [6][7][8]. However, the effects of temperature gradient on the grain growth were not systematically scrutinized and the detail of the thermal pinning remains to be clarified.…”

“…It should be noted that this system has not been subjected to the detailed investigation, since the earlier Monte Carlo studies [6][7][8][9] focused on the grain growth where the growth exponent characterizing the temporal change of the average grain size deviates from 0.5 of the ideal case.…”

Predicting Mesoscale Microstructural Evolution in Electron Beam Welding

“…Significant advances were made by Debroy et al with a three-dimensional (3D) weld simulation. [12][13][14][15] Their studies demonstrated good agreement with experimental grain size distributions at various distances from the centerline of the FZ. Debroy and co-workers focused their analysis on the heat-affected zone (HAZ) surrounding the FZ and excluded the FZ from their simulation domain.…”

Three-dimensional monte carlo simulation of grain growth in zone-refined iron

“…Among the computational models, Monte GRAIN-SIZE changes during processing of metals and Carlo (MC) simulation [7,8,[10][11][12][13][14][15][16][17][18][19][20][21][22] has been widely used to simalloys may affect their strength, toughness, ductility, and ulate grain growth under both isothermal and nonisothermal corrosion resistance. [1] As a result, the prediction and control conditions.…”

“…Analytical models have been developed to undernotable exceptions include some recent works, where calcustand the effects of time and temperature on the grain-size lations were done in three dimensions. [8,14,15,[20][21][22] changes. These models often describe grain growth by the There are considerable computational challenges in confollowing parabolic equation, derived by considering growth ducting meaningful MC calculations.…”