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Grains in H114-T sheet performed irregular shape polygon, a number of subgrains appeared in grains, the amount of dislocations in grains decreased.
Most of the grains in O sheet performed equiaxed grains, as shown in Fig. 2(b).
As shown in Fig. 3(a), there were a large number of dislocations in the H116 sheet.
For the H114-T sheet, in the process of rolling forming a large number of dislocation, but at the same time, many subgrains formed in the annealing treatment.
The number of the dislocation decreased, and the dislocation became sub grain due to the annealing, so the plasticity of the sheet increased [16].

Here Si(i=1,2,3,4) is a variant of S orientation and CSi means the growth of a cube grain into an Si grain.
and indicated number of tiles and grains in the current specimen, respectively.
Here represents an increment of iteration number of the unit time process between the th and i th observation in the N th stage.
Grain size ratio (C/S) that is a ratio of a mean grain area of grains of component C to that of grains belonging to components S and B was 4.
Here, CSi , for example, means the growth of a cube grain into an Si grain.

In the presenting two-dimensional section, this cluster is constituted of 65 grains which are numbered in Fig. 2(a).
Thus, from grain 1 to grain 33, the route mentioned above can be simplified as 1→4→44→58→21→52→33 (Grain 4 and grain 6, grain 58 and grain 19 have the same orientations respectively.
Grains are numbered in (a) which is the orientation contrasted OIM map of this grain-cluster; Grains with the same orientation (The orientations with difference smaller than 1.5°are here recognized as same orientation.) are listed in (b); (c) Twin chain analyzing of these 65 grains; (d) Twin chain analyzing of these 23 orientations.
Grain boundary between grain 44 and grain 34 seems a random grain boundary, but it is actually a higher order Σ3n type misorientation.
(a) (b) (c) (d) (e) (f) (g) (h) The hollow arrow marked boundary in Fig. 3(c) is the grain boundary between grain 44 and grain 34 in Fig. 2(a).

For individual grain volumes, a “grain radius” corresponding to the radius of a sphere, R(t), that had the same volume of the grain could be calculated from Eq. 1.
Initially, a simultaneous transformation was considered with number of nuclei N1 = N2 = 64 and growth rates, G1 = G2.
In these cases, the number of nuclei and growth rates are equal, so phase 1 of the sequential transformation dominates the transformation, with only a relatively small advantage over phase 2, initially transformed to a volume fraction of 0.1.
Grain growth is affected only by its encounter with the neighboring grains, the impingement, so the grain that is situated farther away or has a smaller number of neighboring grains, grows more.
Following of the evolution of the grains one could demonstrate that each grain evolves in a particular way, as expected.

The deformed ferritic material contains a large number of geometrically necessary boundaries with large misorientations, while the martensitic material does only contain original grain boundaries such as prior austenite grain boundaries, packet boundaries and block boundaries.
number of fine grains surrounded by geometrically necessary (GN) boundaries within the initial grains.
However, since there are few high angle boundaries within the blocks, the number of the high angle boundaries existing in the martensitic structure is much smaller than in the deformed ferritic structure.
The number of recrystallized grains is gradually increased and the size of them is enlarged as the softening proceeds (b), and then the deformed structures has been completely replaced by the recrystallized grains when the hardness reaches a stable minimum (c).
The results obtained are summarized as follows: (1) The ferritic material deformed by 80% reduction contains a large number of geometrically necessary boundaries with large misorientations, while the martensitic material does only original grain boundaries.

The grain refinement of pearlite was more obvious when the applied electric current density was higher.
Grain refinement strengthening has been utilized for many kinds of steels.
By means of this treatment some perfect fine-grains were obtained, as later called spark annealing.
It can be seen that electropulsing treatment has obvious effect on grain refinement.
The nucleation is easy to occur on defects, grain boundaries, sub-grain boundaries.

The surface of the grains is uneven.
Sylvinite acquires a milky white color due to a large number of gas-liquid or halite inclusions.
The study of the specific nature of the destruction process of milky white sylvinite reveals a number of successive changes in its shape.
Fracturing along the cleavage is more frequent, and the surface of the mineral becomes spongy due to the large number of cavities.
Clear transparent colorless halite grains and its grains with blue spots, as well as grains, which contain halopelite, are almost not destructed when heated.

(a) (b) Nucleus Frequency and Orientation The recrystallization kinetics as well as the grain size distribution strongly depend on the number of grains nucleating at each particle.
The number of new grains observed in the vicinity of particles was counted, and the dependency of nucleus frequencies on particle size was determined (Fig. 3b).
Fig. 8 (a) Grain size in dependence of the nucleus frequency; (b) Grain size vs. number of nuclei per particle for different particle volume fractions.
The presence of a deformation zone was considered as well as the number of nuclei per particle.
The grain size decreased in a non-linear fashion with increasing nucleus frequency at particles and especially for low nuclei numbers as well as low particle volume fractions.

The results showed that the microstructures of these two kinds of steels are Equiaxed ferrite grains, but the grain sizes are greatly different.
Respectively the average grain size of steel A and B are 24.85μm and 11.85μm, and the average grain size number are 7.4 and 9.5.
Metallographic image analysis software was used for measuring the photos of the figure 1, we can get the average grain size of steel A and steel B are 24.85μm and 11.85μm , respectively, the average grain number of steel A and B are 7.4 and 9.5.
A large number of experimental studies have shown that, uniform ,fine ferrite grains is conductive to the development of {111} texture in the subsequent cold and annealing process.
Respectively the average grain size of steel A and B are 24.85μm and 11.85μm, and the average grain size number are 7.4 and 9.5

Normal grain growth with stationary size distributions of grains was also predicted for the two mechanisms.
A number of investigations have also been conducted in order to take the matrix volume fraction into account for the growth kinetics controlled by diffusion [3-7].
Method of Grain Growth Calculation In a system with a large number of grains in a matrix, the driving force for the growth of a grain is proportional to the difference in curvature between the grain and the critical size grain, which is neither growing nor dissolving [1,2,20].
An individual grain has its own driving force and the largest grain has a maximum ∆gmax, as schematically shown in Fig. 2.
AG: abnormal grains; SGG: stagnant grain growth.