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Sub-micron crystalline silver grain structure were observed using SEM micrographs.
Fig.5(a) shows a uniform small grain with diameter around 100 nm.
The facetted grain shown in Fig.5(b) to 5(f) appear to be nonuniform in grain sizes.
Fig.5(f) shows a higher facetted grain sizes with average grain sizes around 450 nm.
Our results agreed well with others studies [6-9] which report that as the sputtering power increases, the number of energetic atoms and mobility of atoms on substrate surface increases resulting in deposited films became more facetted with larger facetted grain sizes.

It is found that Pr affects the grain size, electrical properties and the dielectric properties of the TiO2-based varistors.
A number of low-voltge varistor materials were reported such as TiO2, SnO2 and SrTiO3 ceramic[4-6].
It can be seen that the grain sizes increase with the increase of dopant concentration, meaning that the dopant can promote growth of grains.
But as a whole, the shape of the grains is almost the same.
Where is the number of grains per unit length and the voltage barrier width.

Initial microstructure contains 100 grains.
This number of the grains correspondents to the average grain size about 80 mm.
The changes of average grain size for entire process can be seen in Fig. 2f.
Depending on temperature, strain and strain rate, the different grain size were obtained.
These parameters influence on the number of new grains and their growth rate.

When the fraction recrystallized, Xrex, is determined, the grain size in the recrystallized regions can be calculated as where is the total number of nuclei.
Here NCube is the number of nuclei formed on old cube grains, NGB the number of grain boundary nuclei and NPSN the number of nuclei from particle stimulated nucleation.
The different nucleation sites are treated independently, so that the total number of active nucleation sites, number of potential nucleation sites and nucleation rate per unit volume respectively, are sums over s = GB, Cube and PSN.
The extended volume fraction of recrystallized grains (which is a key concept of the JMAK-approach), with time-dependent nucleation, is the integral of the volume 4p/3[r(t’,t)]3of grains nucleated at t’ times the number of grains nucleated at t’: , (7) where V and d* are the growth rate and initial diameter of recrystallized grains as given, by Eq. 4 and Eq. 5.
The number of sub-grains that will nucleate during the time dt is the number of available potential nucleation sites (that have not started to grow) , times the increase of overcritical subgrains during time dt.

Nonetheless, a number of negative consequences tend to be possible [2].
While flame heating until 3550C, it was observed that the morphology of the grains retained austenite as evident in Figure 2a, and thus, changes not from the initial grain structure.
In the Figure (1a), shows the Micrograph of initial grain structure and average hardness plots (1b) of the same grain structure at room temperature as HRC 29.
(Slightly higher than those obtained on the initial grain structure).
Figure 4 shows average hardness as HRC 24, 29 29.3 as results; on surface grain structure after flame heated to 550⁰C, on surface of initial grain structure before flame heating and on grains beneath the surface of flame heated samples to 550⁰C respectively.

The higher Fc value, the more round of the α-Al grain is.
As seen from Fig. 2(a), the α-A1 primary grains in the sample were not of uniform size and the fine grained regions were detected.
As seen from Fig. 2(b), the distribution of α-A1 primary grains in the sample were uniform and the average grain size was 38µm with the casting temperature up to 740℃.
Temperature(℃) Temperature(℃) Fig. 3 The relationships of the average grain size and the average equivalent roundness of the squeeze-cast Al-Zn-Mg-Cu alloy with the casting temperature According to the thermodynamics law, the nucleation in molten metal is more and more difficult and the crystal nucleus number which can be kept is less and less with the increasing physics heat supplied by melt temperature.
The grain size constantly decreased with the increasing Al-10RE refiner.

It is shown that dielectric properties of these materials may be modified by a combination of different BTS powders as well as layers number.
Combinations of powders were 0-15, 2.5-15, 7-15, 2-7-10-12 and 2.5-7-10-12-15 (numbers designate mol% of Sn in BTS).
BTS ceramics have been electrically studied as a function of temperature, Sn contents, as well as a function of number of layers.
The grain size is between 20 and 40 µm.
There is an obvious difference in the grain shape between barium titanate sample (polyhedral grains) and BTS ceramics (spread and burst grains).

The average grain size increased with decreasing P content.
IF Steel showed polygonal ferrite grain structure.
The grain size distributions measured by EBSD are shown in Fig. 2.
It can been seen that the average grain size increased with decreasing P content The abnormal growth of partial grains resulted in the increase of average grain size.
The average grain size increased with decreasing P content.

A large number of channels connect the larger open spaces and the sample surface.
Number of pores N In a powder compact there is only one (continuous) pore.
Pore number reaches a maximum when G goes to zero and decreases in the late sintering stage.
Here, VV (solid) is the volume fraction of the solid phase (VV (solid) =1 - VV), and PL(grains) is the number of grains per unit length of the scanning line.
A large number of mechanisms have been identified to be relevant for porosity coarsening.

The parallel algorithm implements the coarse-grained parallelism between computation nodes and fine-grained parallelism between cores within each node.
An accurate model can be obtained by increasing the number of finite element model parameters and improving the calculation precision.
It can reduce the number of model forward calculation [2].
It works well, accessing shared data costs you nothing, and it avoid the overhead of message passing and provides run-time scheduling, fine-grained operation mechanism and coarse-grained operation mechanism as well.
Table 1 shows main parameters of the model, where ipy and ipz represent the number of nodes in the finite element mesh in the Y and Z direction, npp is the maximum number of parameters used, ndd the maximum number of data used, nrc is the number of receiver sites, nfre is the number of frequency number.