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Work piece for CCB was machined parallel to rolling (RD) with a 300mm length, a 20mm width and a 1.5mm thickness, and then was cyclic-bent continuously up to the maximum number of passes, �CCB=40.
The formation of coarse-grained layers was observed also in A5083Al.
Consequently CCB and annealing enable to make coarse-grained surface layers of controllable thickness with number of the CCB passes.
The coarse-grained layer likely retarded corrosion.
The coarse-grained layers had a high corrosion resistance.

In a recent paper [2], the evolution of the microstructure during recovery and recrystallisation was investigated in a number of high-temperature homogenized, hot- and heavily cold-rolled AA3103 samples.
Grains that are much larger than the average grain size appear in the non-homogenized material right after heating to 300ºC (see Figs.2,3).
Fig. 3 Diameter of the largest grain D in the sampled area versus the mean grain size dm.
Since there is no increase in the total number of particles, the solute is precipitated at already existing particles and a coarsening takes place.
Whether grain growth is discontinuous or continuous depends on the original grain size, as indicated.

At the same time, as data of a number of investigations [10] show, a spectrum of boundaries having different misorientations can be formed with plastic deformation.
As seen from the dependence of grain size on deformation temperature, the lower the deformation temperature, the smaller the size of the α- and β- grains (Fig. 1b, 2a).
The microstructure with a grain size of 0.1 µm formed at 450°С.
The study of samples with SMC structure deformed at the lower temperature 550°С has revealed a significant fringe-diffraction contrast, indicating elastic lattice distortion and increased dislocation density in a large number of grains (Fig. 2a).
That is why there are no changes in the grain size-deformation temperature dependence. 2.

Methodology Simulation of grain shape.
The idealized shapes of grains are symmetrical, which can be simulated by combining a fixed number of overlapping disc elements connecting in a rigid way.
Fig.1 Generation algorithm of two kinds of grain shapes and difiniton of grain orientation.
Contact law between grains.
Grain orientation mainly effects the movement including motion and rotation of grains in mesoscopic level.

The mean misorientation of individual grains is defined as the average misorientation between randomly selected pairs of measurements within a grain, where n misorientation pairs are considered for a grain in which n measurements were obtained.
Figure 1 CL image with outline of core of grain in white.
Figure 2 (A) CL image with outline of core of grain in white.
pinning) to within grains that grew (Fig. 7).
Numbers give mean misorientation of grains; grains with low numbers are interpreted to have grown during GBM.

The number N of high angle grain boundaries (HAGB) with misorientations exceeding 15 deg was determined along the length L of the linear intercept and the ratio L/(N+1) was considered as the average interlamellar spacing D of these structures.
This ratio can be regarded as an approximation of the total number of Fig. 4.
Mackenzie 238 high angle lamellar boundaries to the number of initial boundaries.
In their analysis, Hughes and Hansen invoke a coalescence mechanism of dislocation boundaries to explain the decreasing number of new HAGBs in relation to the number of initial boundaries.
Comparison of the average lamellar width with the geometric lamellar width (calculated from the initial grain size by assuming that no additional grain boundaries are generated) revealed that a massive fragmentation process occurred during the first two passes of rolling.

A polycrystalline microstructure made of grains and sub-grains can be obtained in a random or deterministic way.
In the examples shown in this work, the initial mesh was non uniform and anisotropic, taking into account the presence of interfaces between grains and sub-grains.
A convenient way of constructing a large number of grains is given by the Voronoï tesselation.
Probing algorithms can measure particular instantiations of a microstructure, e.g. grain size, grain shape distribution, or crystallographic texture.
The geometry of the boundary can be derived from the distance function φ with: φφ ∇∇= rrr n (5) n rr ⋅∇−=κ (6) If Ng is the number of grains in the considered aggregate, then Eq. 4 can be generalized using Ng level set functions : ( ) ( ) ( ) ( ) ( ) ( ) ∑= +∆ = gN i i i i i xtnxttxETMtxxtV 1 ,,,)(, , r r γκ χ (7) where the function ( )txi,χ is a presence function within the grain i.

Each cell has six state variables: orientation, grain boundary, grain number, the number of recrystallization and color display.
Firstly a random number rand is introduced, then the rand and are compared at each time step. lf rand≤, the cellular becomes DRX nuclei, and cellular state variables are updated accordingly.
Recrystallized Grain Growth.
If, the phagocytosis probability is calculated, where i is the number of recrystallizated cellular at neighbor of current cellular.
Then a random number rand is introduced, and the rand and P are compared at each time step.

Tang et al. [7-10] studied the process of fine grain cast and the heat treatment of fine grain casting wheels.
The calculation shows the grain size of conventional casting sample is ASTM M10-M7 level while the grain size of Microcast-X fine grain casting is ASTM 5-3 level (＜100μm).
The behavior of rupture seems to be positive-break caused by positive stress, while a large number of dimples and two-phase particle occurred in separation surface, indicating the mechanism of rupture to be trans-granular ductile fracture caused by the segregation of microporous.
Firstly, the grain size is refined and dispersion of grains size is decreased (refer to Fig. 1 A~C.
Conclusion 1) Specimen with grain size less than 100μm was achieved by Microcast-X fine grain casting. 2) Microcast-X fine grain casting refines grain and dendrite significantly, and could reduces the segregation of Al, Ti and Ta.

the coarse grains IF steel sheet (CG-IF) and the ZP.
Since the NSUFG/ZP interface has a great number of the structural defects for preferential nucleation sites, great many of nuclei can form on the NSUFG/ZP interface and then immediately connect to each other with enough diffusion mass transfer due to the grain boundary and dislocation diffusion, so that the smooth and thick reaction layer is formed.
On the other hand, small number of nuclei which are formed on the CG/ZP interface with small number of nucleation sites, slowly grow and take much time to connect to each other because of limited mass transfer, resulting in the thin reaction layer in the shape like stone wall as shown in Fig.3.
In the NSUFG layer, the Zn element can penetrate into α-Fe through quite large amounts of grain boundaries by help of the grain boundary diffusion.
This is explained by the increase in driving forces and number of nucleation sites due to the NSUFG structures and the large contribution of rapid diffusion such as grain boundary and dislocation diffusion to the reactions