Subgrain coarsen shares many features with grain growth.
2.
Subgrain rotation is also known as in-situ recrystallization without considerable grain growth.
3.
Sub-grain formation is followed by subgrain coarsening where the average size increases while the number of subgrains decreases.
4.
The process is called subgrain rotation ( SGR ) and can eventually lead to the formation of new grains when the dislocation wall becomes a new grain boundary.
5.
Wu " et al . " describe a process in which dislocation motion becomes restricted due to the small subgrain size and grain rotation becomes more energetically favorable.
6.
Optical microscope and transmission electron microscope ( TEM ) are usually utilized in observing the sequential occurrence of subgrain rotation and local grain boundary bulging, and measuring recrystallized grain size.
7.
Where ? is the dislocation density, G is the shear modulus, b is the Burgers vector of the dislocations, ? is the sub-grain boundary energy and d s is the subgrain size.
8.
Because of a contrasting assumption that subgrain rotation nucleation in continuous DRX ( CDRX ) should be considered for the nucleation rate, Shimizu has come up with another model, which has also been tested in laboratory:
9.
The bulges produced can separate from the original grain to form new grains by the formation of subgrain ( low-angle ) boundaries, which can evolve into grain boundaries, or by migration of the grain boundary.
10.
Rotation recrystallization ( subgrain rotation ) is the progressive misorientation of a subgrain as more dislocations move into the dislocation wall ( a zone of dislocations resulting from climb, cross-slip, and glide ), which increases the crystallographic mismatch across the boundary.
