Comparison of simulated and measured grain volume changes during grain growth

TL;DR

This study compares experimental and simulated 3D grain growth in Ni, revealing size-dependent discrepancies likely due to simplified assumptions in the simulation model.

Contribution

It provides a detailed grain-by-grain comparison highlighting the limitations of current simulation methods in predicting grain growth, especially for small grains.

Findings

Smaller grains are predicted to shrink and vanish faster in simulations.

Errors in grain volume are linked to errors in neighbor counts.

Size dependence suggests need for improved modeling of grain boundary kinetics.

Abstract

The three-dimensional microstructure of Ni, observed after five annealing intervals, was compared to simulations of grain growth using the threshold dynamics method with the assumption of capillarity as the only driving force. A grain-by-grain comparison made it possible to identify the sources of differences between the simulation and experiment. The most significant difference was for grains of the smallest sizes, which the simulation predicted would lose volume and disappear at a greater rate than observed in the experiment. The loss of grains created errors in the numbers of neighbors of the remaining grains, and it was found that errors in the simulated grain volume were correlated to errors in the number of near neighbors. While anisotropic grain boundary properties likely play a role in the differences, the size dependence of the errors suggest that it might be necessary to include a size dependence in the model for grain boundary migration kinetics.