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The number of the passes was 12.
The microstructure investigations of the pointed out samples have revealed a great number of the high-angle grain boundaries and deformation twins in UFGECAP+D+R Cu and the most part of small-angle non-equilibrium grain boundaries in UFGECAP Сu [10].
− is the number of dislocations, blocked at the twin boundary, 3/2 2 )1( fdg!
cTg − = ρ , g − the share of the total dislocation number in the interior grain areas, containing twins, equal to 3/2 2 )1( fdcTg −ρ [9], accumulated at the twin boundaries.
Parameter g which is equal to the total dislocation number in the interior grain areas, containing twins, accumulated at the GB appeared to be 0.224, which corresponds approximately to 2 dislocations.

With traditional methods, Numbers of repetitive experiments will have to do, thus the research work for grinding mechanisms become heavy [3-5].
There are large numbers of abrasive grains whose geometric characteristics and space position are uncertain distributing on the grinding wheel and the cutting characteristics of each grain are different [9-12].
Considering the number of active grains and their radial distribution in actual grinding process, the arithmetic average roughness is modified as followed:                   R d s m R R 8.0 s 0 a 2 1 2 1 (4) where m is the ratio of Rt to Ra, R0 is a empirical constant.
Abrasive grains are numbers of cubes which side length are l.
Interference model between grain and workpiece surface is expressed with grain j and node i, as shown in Fig 1b.

Introduction Recently, industrial products have become increasingly smaller and a greater number of functions are required each year.
As a result, abrasive grains are concentrated and fixed around the tool tip.
The behavior of abrasive grains is then observed.
In order to obtain a more detailed understanding of the behavior of abrasive grains, the density of abrasive grains is less than in the case of the machining and the larger abrasive grains are used.
When the applied voltage is low, the electrophoretic force acting on abrasive grains is small, and abrasive grains cannot closely approach the micro tool (Fig. 6(b)).

Marx str., Ufa 450000 Russia, email: RZValiev@mail.rb.ru Keywords: superplasticity, ultrafin� -grain� d alloys, severe plastic deformation, grain boundaries Abstract.
Special attention is paid to microstructural dynamics, i.e. a grain growth and grain boundary sliding at low temperature and high strain rate superplasticity in ultrafine-grained alloys.
After heating up to temperature of superplastic testing there was some grain growth, but the mean grain size was still less than 0.3-0.5 µm (Fig. 1).
We observed a visible grain growth leading to an average grain size in gage section of about 1-2 µm.
Concluding remarks The applications of SPD techniques for processing of UFG structures have provided an opportunity to attain enhanced superplastic properties, namely low temperature and high strain rate superplasticity, in a number of alloys.

EMF measurements were conducted under fuel cell conditions to evaluate the ionic transport number of the composites.
As a result, the conductivity at the grain boundary was improved.
The ionic transport number was calculated from the ratio of the measured EMF to theoretical value [15].
The ion transport number is more than 0.9 at 750 °C, slightly increasing with lowering temperature.
High ion transport numbers indicate that this material is a good ion conductor over the temperature range of interest.

However, practical application of such materials requires solving a number of materials science problems such as the decrease of ordered phase formation temperature, formation of its predominantly oriented grains and the increase of coercivity.
A number of modern studies aimed on solving problems mentioned above have been analyzed.
A large number of studies are aimed on solving these problems.
Grain boundary diffusion of Ag may facilitate the increase of coercivity of films due to the decrease of magnetic interaction in between grains of L10-FePt phase (grains magnetic isolation).
Summary We have examined a number of modern works that discuss the ways of L10-FePt ordered phase formation temperature decrease, formation of predominant orientation of its grains and enhancement of its coercivity.

In this study, a fine nanocrystalline structure with an extremely number of α-Fe grains with the similar size of ~ 30 nm was obtained.
Fe-based nanocrystalline powders particularly usually show low power loss on the high frequency band, higher performance with a thinner layer due to higher saturation magnetization because of a large number of α-Fe grain precipitation as well as higher permeability than those of the conventional materials.
An extremely large number of α-Fe grains with very fine grain size of ~ 25 nm were precipitated in the amorphous matrix.
On the other hand, the crystallization degree became larger as a large number of α-Fe nanocrystalline grains precipitated from amorphous phase with increasing Tq.
It can be observed that these samples have a fine nanocrystalline structure with an extremely number of α-Fe grains with the similar size (28, 27 and 20 nm when Tq is 773, 798 and 823 K, respectively) below 30 nm in general dispersed in amorphous phase.

The average grain size, grain size distribution and volume fraction of dynamic recrystallization were taken into account.
Lower dislocation density and distortion energy with smaller deformation leads to a lower number of nucleation on the blade rabbet.
However, the velocity of nucleation is faster compared with that of grain growth so that the grain is finer.
The grain size number of dynamic recrystallization in the middle of blade body is 9~10 and the grain size number in the leading and back edge of blade body is 10~11.
The size number of recrystallized grains in the blade rabbet and body are 8 and 9~10 respectively according to the experimental data.

In the process of describing a grinding wheel, the grit number is related to the mesh number of the screens used to sort the grains.
(Table 1) Clearly, when counting the static grain density, there is a theoretical upper bound to their number.
For a given grit number, they were expressed as gavgdµ= (3) ( )/3 gmax gavgd d σ= − (4) To generate the wheel topography, the grinding wheel is mesh with a grain interval.
The grain interval is the distance between two adjacent grains.
And the effective grains number is quite useful in predicting the finished workpiece surface.

The number of hydrogen atoms in the NDSR or HLSAD, per the dislocation length of b, can be described [2] as nH⊥ ≈ (CΣ - C) / ρ⊥ b2
In this connection, it ought to be emphasized that in a number of works, for instance [18,22,41, 42] some inadequate concept is used.
For a number of cases, this results [1] in reasonable values of ∆HB ≈ 40-20 kJ mol-1 and, correspondingly, reasonable values of K⊥ (increasing with reduction of CΣ).
Consideration of the Mössbauer and Diffusion Data on CLNS of Fe at Grain Boundaries in Al.
Numerous surface nodules, made of virtually pure nickel, were visible within the grains.