Microstructure grain growth

Figure 9.41 For an idealized initial stage microstructure, grain growth increases the total grain boundary area between two spheres. The dihedral angle constraint at the surface of the sphere creates a boundary curvature that opposes grain growth.

Grain growth and other microstructural changes. When a deformed metal is heated, it will recrysiallise, that is to say, a new population of crystal grains will... 

The phase-field simulations reproduce a wide range of microstructural phenomena such as dendrite formation in supercooled fixed-stoichiometry systems [10], dendrite formation and segregation patterns in constitutionally supercooled alloy systems [11], elastic interactions between precipitates [12], and polycrystalline solidification, impingement, and grain growth [6]. 

The ratio of additive combinations also influences the microstructural evolution. For instance, with decreasing ratio of Y203/Al203 the microstructure becomes finer and the aspect ratio lower [301, 302]. MgO as well as CaO additives accelerate the grain growth and increase the aspect ratio [303, 304]. 

Painter, G.S., Becher, P.F., Shelton, W.A., Satet, R.L. and Hoffmann, M.J., (2004), First-principles study of rare-earth effects on grain growth and microstructure in P-Si3N4 ceramics , Phys. Rev. B, 70, article 144108. 

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