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The effects of stochastic distribution of grain nuclei, grain size and grain morphology are carried out for the validity of the simulated microstructure.
According to metallurgy, the growth of grain is from the grain nucleus in all the directions at the same speed until it encounters with others grains.
Each grain is assumed to be orthotropic and the orientation of the principal material directions differs from grain to grain.
In fact, these grain orientations for the grains composed of the microstructure are generated by a random number generating routine.
As described above, the grain orientations can be generated with a random number generating routine.

TEM results have also been used in order to evaluate grain size evolution.
It is reasonable to conclude that there is not a continue evolution of the material with increasing number of passes through ECAP processing.
Highly deformed grains some of them with large number of interior dislocations are present in the sample.
However dislocations seem to be localized within the grains.
Some new boundaries begin to appear changing the appearance of the grains.

φ=0° φ=45° φ=65° (a) (b) An investigation of the nucleus density only in one plane does not give sufficient information about the absolute nuclei number because grains can nucleate and grow also in other directions.
The nucleus number distribution, in general, has also a tendency to increase with the band size.
For bands with 20 to 30 µm length average number was about 2-4 nuclei, for larger bands from 4 to 6.
Therefore, the number of nuclei has been taken not per grain, but per band length.
In the first case, if several separated bands are introduced instead of one large deformed Cube grain in the simulated deformed microstructure, the number of possible nucleation sites on the Cube-S boundaries is increased, which increases the volume fraction of RX Cube grains.

This serial sectioning technique was used to investigate the recrystallization behaviour of a particle-containing nickel alloy, which revealed a number of features of the recrystallizing grains that are not clearly evident in 2D EBSD micrographs such as clear evidence of particle stimulated nucleation (PSN) and twin formation and growth during PSN.
Figure 6: (a) 2D-EBSD section showing three recrystallizing grains (arrowed).
(a) (b) (c) (d) Figure 6a shows another other set of twinned grains (1 and 2) as well as a fine grain that did not grow during annealing (grain 3).
The pole figure given in Fig. 6b shows that grains 1-2 and 2-3 are twin related and all grains are misoriented 5-15° from the deformation substructure (matrix).
A possible mechanism of formation of twinned grains during PSN is given elsewhere [13].

Scandium addition to the alloy enables reducing the solidification processes and degree of segregation along the grain boundaries, as well as localizing partial melting of the grains without formation of coarse eutectic interlayers.
At present scandium influence on the properties of many aluminium alloys has been studied, and a number of promising scandium-containing alloys have been developed [7].
Heating above solidus temperature leads to partial melting of low-melting structural components along the grain boundaries, grain coarsening and formation of brittle interlayers and microdefects along the grain boundaries.
Grain structure remains unrecrystallized.
Compared to excess phases, number of phases of eutectic origin in the base metal increases 2-3 times.

The strain rate sensitivity is found to increase slightly in ultrafine-grained Cu compared with conventional Cu, but decrease in ultrafine-grained Fe and Ti relative to their coarse-grained counterparts.
Such UFG metals usually contain a large number of dislocations in a heavily deformed microstructure.
The dislocations produced during SPD have organized into grain boundaries and the dislocation density is low inside the grains.
In actuality, it only means that the number of dislocations that get stored into the nc/UFG microsctructure during deformation is no longer significant to appreciably elevate the flow stress over the strain range tested.
Note that a large fraction of high-angle grain boundaries are indeed present to facilitate grain boundary sliding.

The DRX grain size increases as strain rate decreases.
In this way, the microstructure such as DRX grains and sub-grains could be observed and analyzed on a Tecnai G 2 20 TEM.
At 250°C, there are a large number of high density dislocation tangling in grains, leading to the forming of dislocation cells(Fig.1a).
As ε& increases to 0. 1s-1, the grain size decreases and the grain boundaries of DRX tend to straight, revealing that the DRX grains grew up to some extend(Fig.2b).
The grain size of DRX increases with decreasing strain rate.

The equiaxed grain in 2# steel with higher coiling temperature is the more obvious.
From Fig. 1, it can be seen the microstructure obviously show pancake grain in 1# steel(seen in Fig. 1(a)), but the grains display equiaxed ones in 2# steel and 3# steel(seen in Fig. 1(b) and (c)) and equiaxed grain is the most obvious in 2# steel.
From Fig. 2, it can be seen the microstructures all compose of ferrite and cementite, but free cementite is dominant with minute numbers of line cementites in 1# steel, as shown in Fig. 2(a).
Large numbers of line cementites are observed in 2# steel and 3# steel, as shown in Fig. 2(b) and (c).
The equiaxed grain in the steel with high coiling temperature is the most obvious.

Number of feedbacks with each control method.
for (a) Grain-oriented electrical steel sheet and (b) Amorphous ribbon.
Fig.3 shows number of feedbacks with each control method.
The number of feedbacks when the control is complete is as follows.
In case of the Grain-oriented electrical steel sheet, the number of feedbacks are 24 times (CRM), 22 times (BCM), and 1 time (IBCM).

That number represents on electro winning cells half million of lead base anodes (Pb-0.07% Ca-1.3% Sn), with dimensions of 1 x 1 meters of section and 6, 7.5 and 9 mm thickness.
The shape and size of the grains were determined by metallographic analysis.
Note that anodes with 75% of cold rolling reduction have very small grain size.
Grain size of anodes with strain.
Corrosion rate of the anodes versus their average grain size.