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The orientation distribution of the first nuclei, their displacement, size and number evolution can be studied.
The maximum number of nuclei is observed after the recovery period at the beginning of the recrystallization (fig. 1a).
After this moment, the number of nuclei decreases as grain growth develops.
Because of limited number of grains in studied EBSD maps, it is obvious that the texture simulated from EBSD does not reproduce exactly the global texture obtained by diffraction experiments.
However the main features in texture evolution can be seen even by use of the limited number of grains.

Significant grain refinement was achieved using high deformation degree per pass (> 30 %).
final thickness [mm] number of passes pass reduction [%] Schedule 1 1.25 1 46 1 56 Schedule 2 1.25 2 ≤ 30 1 ≤ 35 Schedule 3 1.25 3 ≤ 26 1 ≤ 30 The rolling speed of finish-rolling was 80-120 m/min with a rolling temperature in the range of 270-360°C depending on number of rolling passes and final thickness.
According to [4] a fine grained region would develop at former grain boundaries of large grains.
The homogenized condition with an inhomogeneous microstructure provides the grain grow in the initial large grain boundaries after the roughing.
Finish-rolling The influence of deformation on the process stability and properties of the final strip was examined by means of variation for the number of rolling passes and pass reductions (see Table 2).

At this time the formation of grain roundness is very bad, and the grain size is not uniform.
As shown, at this time the number of dendrites has an observabe ruduction , many dendrites were interrupted, but there are still a few residual dendrites.
A lot of grain shapes have become a long strip, but also there is a little number of spherical or globular classes .
This is because at this time under the conditions of process parameters, the exit temperature is in the range of the semi-solid aluminum alloy, a large number of solid-phase has been made during the flowing process of the aluminum alloy, which makes the interactive shearing between grains to enhance greatly, while the dendrite arm has just been formed, it will be cut off by the interactive shearing between grains, so the growth of dendrites has been restrained.
As can be seen from the Figure 7, at this time a large number of dendrites appear, while other dendrites have been cut off to become a long strip, the grain shape is very rules, size is also very uneven, the roundness of grains is also very poor.

Volume percent of grains in wheel is about 54~58%.
So the number of grains on the working surface of the wheel per unit millimeter is N=1.66mm-1.
When the workpiece was ground by wheel with a speed of 1350rpm, the number of grains passes through the grinding zone per unit time can be gotten: .
Each grain has different exposed heights.
Then these active grains would produce “flash” impulses.

The Effect of Magnetic Field on Kinetics of Grain Boundary Grooving in Iron E.
It was shown that external magnetic field of 5 kOe slows down the kinetics of grain boundary grooving in iron at 750 °C by about one order of magnitude.
The average grain size after this high-temperature annealing was 30 µm.
AFM topography image (a) and the line profile taken along the white path (b) for Fe sample annealed for 2 h at 750 °C in magnetic field of 5 kOe. 0 1 2 3 0 10 20 30 wc=1.75 µm (a) Number of GBs w, µm 0 1 2 3 0 20 40 60 Number of GBs w, µm (b) wc=1.01 µm the magnetic field leads to the diminishing of size of the GB grooves, which, according to Eq. (1), is associated with the decrease of surface diffusivity.
Watanabe in "Recrystallization and Grain Growth", G.

Introduction Environmentally-induced intergranular stress corrosion cracking (IGSCC) is known to be a damaging mode in number of nickel-base alloys used in pressurized water reactors (PWR) of nuclear power plants [1-5].
Indeed, the migration of chromium atoms towards the surface throughout the lattice generates a contraction of alloy grains, hence stressed grain boundaries.
The microstructure of the model alloys was characterized by equiaxed small grains (ASTM grain size number = 8 - 9) and very few carbides (Fig. 1).
The layer appears not to have been a compact continuous one but instead was formed of discrete separated grains.
Another layer of very small oxide grains can also be distinguished underneath the crystallites.

These simulations couple a grain size and strain dependant viscous rheology with grain size reduction and grain growth processes.
The list of active processes includes dislocation glide, twinning, various types of sub-grain formation, grain boundary sliding, grain and sub-grain boundary migration, grain boundary diffusion, lattice diffusion, fracturing, frictional sliding, and fluid flow [5].
Grain Size Reduction There are several processes that could result in a decrease in grain size in a rock including fracturing, twinning, kinking, metamorphic re-equilibration and rotation recrystallization, all of which are replaced in these experiments by a single process that inserts an 1 http://www.microstructure.uni-tuebingen.de/elle Journal Title and Volume Number (to be inserted by the publisher) 3 approximately straight high angle grain boundary in a grain.
Grain Growth We have used a simple grain boundary migration algorithm based only on local grain boundary curvature to describe a generic grain size increase process.
Journal Title and Volume Number (to be inserted by the publisher) 5 Figure 2.

The banded structure and grain size were evaluated according to ASTM E1268-01 and GB/T 6394-2002.
For sample 1, the banded structure was almost eliminated after the heat treatment process and the band structure grade decreased to grade 2.5; also, the grain size became finer and the grain size grade increased to grade 8.8.
The sample 2 had a banded structure grade of 3 and grain size grade of 8.0.
In addition, banded structure was more prone to crack, especially in the coarse grain zone.
For that of sample 2, size was small but huge in number, it also existed some long strip type sulfide inclusions.

The sample preparation spin coating number is 6, the average grain size is in nanometer level, and the thermal treatment temperature is 450, 500, 550, 600℃, respectively.
The D values of the average size of corresponding grains are shown in table 2.
Table 2 Average grain size of doped ZnO thin films of Al and Co sample number Diffraction peaks FWHM D[nm] Al001 100 0.478 17.7 002 0.451 18.9 101 0.485 17.6 Al002 100 0.321 27.1 002 0.353 24.6 101 0.389 22.2 Al003 100 0.336 25.7 002 0.313 28.0 101 0.395 21.9 Al004 100 0.272 32.7 002 0.297 29.7 101 0.352 24.7 Obviously, as the sintering temperature rises, the fwhm of the diffraction peak gradually decreases and the average grain sizes grow, indicating that the higher the temperature is , the better the crystallinity of Zn0.98-xCo0.02AlxO films is and the less defects the films have.
Samples with smaller grain sizes will increase the scattering of light on the surface of the films and reduce transmissivity.
But relative to other samples, Sample Al004 will move toward the direction with higher energy, which is due to large grain size of the films of sample Al004, few defects of grain boundary, small resistivity and higher carrier concentration.

Introduction The abrasive processing is the primary processing technology of ceramic materials, but the purity of the abrasive grains will impact surface quality of the workpiece, now the semi-fixed abrasive processing is proposed by the authors [1].
It has the good processing characteristic, which integrates with solid abrasive processing and free abrasive processing technology, and it can reduce or even eliminate the defects induced by large abrasive grains in the grinding due to its 'trap' effect.
In simulation, the indenter is imagined as large abrasive grain, and the SAP is soft, which can be embedded the indenter under processing velocity.
Table 1 Model parameters number d [µm] Density [kg·m-3] Kn [N·m-1 ] Ks [N·m-1 ] µ particle 2511 3～3.75 2970 5.0×106 1.1×106 0.9 Wall 4 - - 1.0×10 7 1.0×107 0.5 porosity pb_kn [N·m-3 ] pb_ks [N·m-3 ] pb_rad pb_nstren [N·m-2 ] pb_sstren [N·m-2 ] particle 0.22 5×10 10 5×1010 0.5 1×108 1×108 Wall - - - - - - Table 2 Parameters of walls Wall5 Wall6 number 1 1 Kn[N·m-1] 1.0×1010 1.0×1010 Ks[N·m-1] 1.0×1010 1.0×1010 After producing the SAP, then the indenter can be generated by PFC, in simulation, wall5 and 6 are imagined as the indenter, and the degree of indenter can be also changed, and three kinds of angles are simulated.
Conclusions This paper preliminary studies of simulation on the indentation of large grain in the SAP, and the 'trap' effect of SAP is validated, and the size of large grain is an influence factor in the 'trap' effect of SAP.