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And some crystal defects such as subgrains and grain boundaries can be seen clearly from the amplified morphologies of Fig. 2 (a) and (b).
The amplified morphologies of Fig. 2 (a) and (b) show that the substitution of Mn for Ni renders a clear refinement of the grains in the as-spun alloy.
Secondly, the refined grain by substituting Ni with Mn and melt spinning is favourable to the discharge capacity because the grain boundaries possess the distribution of the maximum hydrogen concentrations.
The evolution of the RN values of the as-cast and spun Mg20Ni10-xMnx (x=0-4) alloys with the cycle number is described in Fig. 4.
It is indubitable that the diffusion of hydrogen atoms is markedly easier in a crystal alloy than in an amorphous one due to the fact that the large number of interfaces and grain boundaries can act available as paths for hydrogen diffusion.

Eight hours oxidation results in some locally extruded oxide grains (Fig. 6C), while 24-hrs oxidation leads to non-uniform scale with blade-like grains and other irregular shapes of grains (Fig. 6D).
The thin blade- and needle- like grains observed at lowest temperature (Fig. 9A) are at high temperatures replaced by thicker grains (Fig. 9B and C).
However, in the case of highly irregular scale, as for blade- or needle-like grains covering the scale surface, the profile is broadened which may result in its shape observed in Fig. 10D.
In all cases either flat scales or blade- and needle-like or pyramid shaped-grains are observed.
θ θ θ δ FeCrAl δ θ FeCrAl FeCrAl θ δ δ 2-Theta-Scale Lin (Cps) 0 100 200 300 400 500 10 20 30 40 50 60 70 80 0 0,0001 0,0002 0,0003 0,0004 0,0005 0,0006 0,0007 1 2 3 4 5 CYCLE NUMBER ∆∆∆∆m/q [g/cm2] A B C 0 20 40 60 80 0.0 0.2 0.4 0.6 0.8 1.0 Relative SIMS intensity Depth [number of sputter cycles] 1616O 1818O -- A 0 20 40 60 80 100 0.0 0.2 0.4 0.6 0.8 1.0 Relative SIMS intensity Depth [number of sputter cycles] 16-16O 18-18O- C 0 10 20 30 40 50 0.0 0.2 0.4 0.6 0.8 1.0 Relative SIMS Intensity Depth [number of sputter cycles] 16 O _ 18 O _ E 0 20 40 60 80 0,0 0,2 0,4 0,6 0,8 1,0 Relative SIMS intensity Depth [number of sputter cycles] 16-16O 18-18OB 0 20 40 60 80 100 0.0 0.2 0.4 0.6 0.8 1.0 Relative SIMS Intensity Depth [number of sputter cycles] 1616 O 1818 O -- D 0 10 20 30 40 50 0.0 0.2 0.4 0.6 0.8 1.0 Relative SIMS Intensity Depth [number of sputter

The irregular rough surface cannot control the abrasive grains during polishing, and the slurry cannot be distributed over the polishing pad surface uniformly.
Withapproximately 7,600 diamond grits in each conditioner, the aim was to increase the number of effective diamond grits by doubling the number of small diamond disks.
This suggests that although the DG diamond conditioner has a large number of diamond grits, approximately 20,000 grits, only a few prominent diamond grits exhibit cutting ability.
The cutting resistance can be reduced to distribute the force uniformly, and the pressure of effective working grains contacting the wafer can be reduced.
The number of workable diamond grits of the broken diamond-12 conditioner is almost half that of the diamond-24 conditioner; several abnormal prominent diamond grits determine the final result.

At a higher Si content the films become poorly crystallized (grain size < 3 nm) [9].
During the film growth, the Si atoms segregate at the grain surface.
Above the limit of solubility, at higher Si contents, the NbN:Si grains cannot accept the whole quantity of added Si atoms which diffuse to the grain boundaries.
Considering that the segregated Si atoms occupy the sites of Nb atoms on the crystallite surface, the Si surface coverage is defined as the ratio between the number of segregated atoms on the crystallite surface and the number of the Nb surface sites of the crystallite.
In Region 2 (4 ≤ CSi≤7 at.%) a fraction of Si atoms segregates at the grain boundaries.

In the fabrication process of the O-SP, a number of crystal-oriented sheets were stripped from the PET film, laminated and pressed together.
A number of sheets with Pt paste printed were stripped from the PET film, laminated and pressed together.
Many rodlike grains were observed in the surface of the randomly oriented sheet, as shown in Fig. 1(a).
The grains were crystal-oriented in the 2m 2m 2m 2m Fig. 2.
As shown in Fig. 6(b), rodlike grains aligned normal to the internal electrodes.

Therefore, high stain rate also can result in higher strength through finer the austenite grain size [5].
The ferrite formed along the prior austenite grain boundaries.
But the ferrite grain boundaries are not continuous (see in Fig. 1(a)).
As a result, the microstructure will be formed by a network of ferrite grains of unequal size.
These precipitations can restrict the prior austenite grain size and fine the proeutectoid ferrite grain size because the grain boundaries represent sites for proeutectoid ferrite nucleation.

Macroscopic the alloy 1 structure presented in both cases (thermal recovered, a) and quenched at room temperature, d)) a homogeneous structure with well defined grains.
For thermal recovered sample the grains dimensions vary between 110 and 145 µm length, around 50 areas of the same sample were investigated and measured and an average of 25 grains for recovered sample and 15 grains for water quenched on a 0.25 mm2 surface, comparing with the water cooled sample that present reduced areas with small grains, around 50 µm in length, and areas with long martensitic variants with lengths bigger than 200 µm being a favorable structure for shape memory effect.
In the first case, the hardened alloy, macro-structural aspects presented martensitic grains with lengths between 50 and 150 µm, around 50 areas of the same sample were investigated and measured and an average of 28 grains for thermal recovered sample and 2 grains for quenching heat treated on a 0.25 mm2 surface, compared with the quenched sample that presents big areas with martensitic variants, around 500 µm in length, favorable for shape memory effect.
Acknowledgement This work was supported by a grant of the Romanian National Authority for Scientific Research, CNCS – UEFISCDI, project number PN-II-RU-PD-2011-3-0186.
Jang, Effect of grain refinement on phase transformation behaviour and mechanical properties of Cu-based alloy, Trans.

Effects of SiC grains gradation, pore formers content, molding pressure and soaking time on the bending strength and porosity of ceramic filter plate was studied.
Fig. 1 shows that effects of SiC with various grain size distribution on bending strength and porosity of the samples.
It can be seen that the porosity can be tuned by the change of SiC grain size distribution.
With mass ratio of SiC grain size distribution increase, porosity of the samples increases sharply, and bending strength of the sample decreases.
It can be due to that specific surface area of SiC with the small particle size is large and the particle number is more than those with large particle size.

Evaluation of measuring palisander wood dust was divided according to the size range of particles and the number of measured values in a given interval and the percentage was calculated.
Table 3 Views frequency range by grain size oak (Quercus robur L.)
In palisander dust there is the greatest number of dust particles - 78.31% represented sized from 10 μm to 100 μm.
To cause dust explosion is necessary to meet the particle size, the mean grain size, which is 400 μm.
Powders with small grain size are more hazardous for evidence of explosion.

There has been a large number of studies focusing on bridging the microstructure and macroscopic mechanical properties by both experimental and numerical methods.
Grain reconstruction and analysis have been carried out by MATLAB/MTEX toolbox [11]. 15º misorientation threshold was used for the grain reconstruction.
The investigated material has an average grain size of 16 μm and mean grain shape aspect ratio of 1:0.681:0.662.
During the RVE generation process, the most representative and effective factors are element size and number, which are corresponding to the final RVE size.
The finally optimized RVE model is shown in Fig. 2, which contains 3165 Al grains.