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The mechanisms of recrystallization nucleation in fcc bicrystals have been the subject of a number of previous studies [1-8], but usually without the advantages of modern EBSD techniques for detailed microtexture analysis.
The orientations of the grains composing the bicrystals are chosen to represent grains of unstable or stable deformation behaviour.
recrystallized grain and the deformed neighbourhood, taken globally for the regions around both grains is not very clear.
In Fig. 3a one of the recrystallized grains, R1, can be seen to grow into the deformed grains of both 'shear' and 'Goss' orientations.
As can be seen on the {111} pole figure (grain R2), this grain's inability to cross the grain boundary may result from the absence of a common {111} plane with a crystallite of 'Goss' orientation.

At final stage, the twins are saturated by filling in most part of the grains.
These recrystallized grains grow further with the increase of annealing temperature.
For the homogenized Mg alloy ingots, the orientation of their inside grains is usually distributed randomly, which means some of the grains are favourable for twinning while some are favourable for basal slip.
This can be verified by Fig. 4a, that is, twins were not formed in all of the grains.
Combined analysis of the results, we found that when the strain is very small (e.g. ε = 0.005), the relative intensity between {100} and {0002} diffraction peaks just undergoes a minor change with only a small number of twins emerge (Fig. 3).

The results show that, the number of spherical Al3Zr particles is determined by the pretreatment, and that the size is determined by the homogenization.
Introduction It has been experimentally documented [1-4] that the function of addition of Zr in aluminum alloys as a role of grain refiner and recrystallization inhibitor.
In order to provide experimentally veritable results from the TEM investigation, for each sample, at least 3 grains were investigated and at least 5 areas for each grain were imaged.
But the number of Al3Zr particles increase with the time of pretreatment prolonged and the temperature of the pretreatment rise.
According to this report, there will be form a certain number of atom cluster when the holding time is less than 24h at the temperature of 460˚C.

Grain boundary sliding.
Grain boundary sliding (GBS) occurs due to shear tractions acting tangent to the grain boundary.
(3) The superscript indicates the number of assumed boundary planes which ranges from one to 12 in this case.
With this assumption atoms only move around one grain and cannot move from one grain to another grain and grain boundary migration cannot be modeled.
The grain has a spherical shape.

Recently, a large number of papers have been published in which an attempt has been made to quantify the relationship between the structure and properties of steel [1].
In many studies, (e.g. [2, 3]), it is noted, for example, that the most studied effect in the process of hardening is the effect of grain grinding.
The dependence of the yield strength on grain size is well described by the Hall–Petch relationship.
A similar dependence of grain size (d-1/2) was used to describe the viscosity as a function of the brittle transition temperature [4, 5].
However, in turn, the sizes of primary grains are determined by the sizes of dendritic crystals.

Together, these two aspects control grain refinement and homogenization.
Multiple layers or a thicker reinforcement phase can be used to increase the number of dispersions; however, multiple passes may be necessary for the proper breakup and uniform distribution of reinforcements.
The movement of dislocations may be harder, with a reduction in the grain size.
The addition of reinforcement particles, during FSP, may also aid in grain refinement; the existence of second phase particles (pinning effect) obstructs the direction of grain boundary which is migrating because of recrystallization and grain growth [10][11].
Grain size increases usually with increasing the rotational speed due to excessive heating and grain growth; conversely, Grain size decreases with increasing the traverse speed.

At the same time, it also plays a role in grain refinement to some extent.
When the molybdenum content is small (Fig. 2, (a)), abnormal grain growth was found, and the thickness in the rim phase of some abnormal growth grains is large.
While molybdenum was added in the form of pure metallic powder, the grain size distribution was wide although the size of some grains was relatively small.
The number of the irregular shape grains increased and the number of round grains was small.
Effect of carbide additions on grain growth in TiC-Ni cermets[J].

Microstructure evolution and tensile properties were studied in a bainitic pipeline steel grade by performing a number of physical simulations on samples machined out of an industrially produced transfer bar.
During the rough rolling the austenite grain size is refined due to repeated cycles of work hardening and the recrystallization process.
The austenite status at this stage - regarding the prior austenite grain size (PAGS) and precipitation - simulates the condition of austenite after the roughing process.
On the other hand, a value of 60 s for tV was enough to attain the saturation point for large prior austenite grains deformed at high temperature (Fig. 5b and 5e).
Summary Microstructure evolution and tensile properties were studied in a pipeline steel grade API-X80 by performing a number of physical simulations on samples machined out of an industrially produced transfer bar.

Because the size of the slab grain size decides the grain size of hot rolling plate, the grain of A group is bigger than that of B group after hot rolling.
There are no differences in the grain size of the finished product.
In the same continuous annealing process, the degree of grain breaking is recovery, recrystallization and grain growth process again, so the final grain size is the same.
Because of the cold rolling process, a large number of shear zones are formed, the larger the grain size, the higher the shear zone distribution.
Since the shear zone can be highly stored, the recrystallization grains occur preferentially in the shear zone and the nucleation of the grains in the shear zone.

The amount of strain estimated from Eq.1 (which obtained from the count of rotational number at each temperature) is described in Table 2.
While, a very small amount of the new fine crystal grains are observed along the original crystal grain boundary due to dynamic recrystallization during warm working [2].
Very fine crystal grain along the grain boundary was able to be confirmed in each microstructures.
When working temperature at 473K or more, the deformation twins cannot be seen and very small new fine crystal grains are observed along the original crystal grain boundary due to dynamic recrystallization.
The amount of small fine crystal grains increase with increase of working temperature.