Grain growth
![Computer Simulation of Grain Growth in 3D using phase field model. Click to see the animation.](/Images/godic/202501/16/Grgr3d_small3456.gif")
![Distinction between continuous (normal) grain growth, where all grains grow at roughly the same rate, and discontinuous (abnormal) grain growth, where one grain grows at a much greater rate than its neighbours.](/Images/godic/202501/16/ContinuousDiscontinuousAnnealing3456.png")
Grain growth is the increase in size of grains (crystallites) in a material at high temperature. This occurs when recovery and recrystallisation are complete and further reduction in the internal energy can only be achieved by reducing the total area of grain boundary. The term is commonly used in metallurgy but is also used in reference to ceramics and minerals.