Demonstrating the temperature gradient impact on grain growth in UO₂ using the phase field method

Grain boundaries (GBs) are driven to migrate up a temperature gradient. In this work, we use a phase field model to investigate the impact of temperature gradients on isotropic grain growth. GB motion in 2D UO₂ polycrystals is predicted under increasing temperature gradients. We find that the temperature gradient does not significantly impact the average grain growth behavior because the curvature driving force is dominant. However, it does cause significant local migration of the individual grains. In addition, the temperature dependence of the GB mobility results in larger grains in the hot portion of the polycrystal.