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The marking of samples in presented figures includes the number of ECAP passes and letter M, designating the middle region of rod.
A significant decrease of lattice distortion ε in Cu rods by increase in the number of ECAP passes indicates, that in most grains distinct perfection of the crystalline lattice takes place
(4) The most probable value of dislocation density ρ for Cu rods varies in limits 1x10 13 ÷ 1x10 14 m-2 and decreases with the number of ECAP passes.
Thus, presented PF visualize the texture inhomogeneity through the cross-section of studied rods as well as changes of this inhomogeneity with the number of ECAP passes.
Marking includes number of ECAP passes and region of section (T - top, M - middle, B - bottom).

The evolution of the structures with number of ARB cycle was examined and discussed in this investigate. 1.
Physically, a small amount of recrystallization grains were found near grain boundaries and twin grains.
Structure of Mg layer after first cycle contains large-deformation grains, twin grains and recrystallization, fig.3.a.
In addition, the hardness was raised, due to dislocation formed in the grains and grain refinement.
Due to dislocation formed in the grains and grain refinement.

F(g)max = 9 F(g) = 6 F(g) = 6,3 F(g) = 6 TD RD ND (a) (b) Fig. 2 : (a): Substructure of the {111}<110> grains after 35% tensile strain, (b): diagonal size of diamond cells, the number of measurements N = 60.
TD RD ND 0,2 0,4 0,6 0,8 1,0 0 5 10 15 Frequency Diameter (µm) N = 60 (a) (b) Fig. 3 : (a): Substructure of the {001}<110> grains after 35% tensile strain, (b): size of equiaxed cells, the number of measurements N = 60.
Nuclei G1 and G2 are located at the grain boundary, G3 is located at the grain centre.
The "bulging" is the growth of a nucleus into the neighbouring grain of different orientation by migration of the grain boundary.
Thus, if the nucleus is formed at the grain boundary (or at the grain boundary vicinity), it invades easily its neighbouring grain.

Though there are a number of papers on the materials of CCTO, the mechanism of the giant dielectric constant is still not clear [3-6].
This indicates that the abnormal grain growth occurs.
In Fig.2 (a), some large grains are observed in size of about 30-70 µm, whereas, some grains are as small as 2 µm.
The residual pores are observed within the large grains, indicative of fast grain growth.
Nevertheless, the grain size decreases with the Fig.1.

Experimental results show that a considerable number of spherical γ’ phase distributed uniformly under solution at 982℃ solution for 1h and 718℃ aging for 1h.
Results and Discussion Microstructures of GH2132 after different aging treatments are shown in figure 1.Figure 1(a) displays equiaxial polygon grains after aging treatment and the grain boundaries are clear.
The carbides not only reduce the binding force of the grain boundary and damage the continuity of the grain boundary, but also become a source of crack and make the alloy occur brittle fracture.
(2) After the secondary aging, large particles of carbide precipitation appeared in grain boundary, which not only reduce the binding force of the grain boundary and damage the continuity of the grain boundary, but also become a source of crack and make the alloy occur brittle fracture.
This paper is supported by Guiyang Municipal Science and Technology Project (Contract Number (2012207)03,(2012101)2-5), and Guizhou Industrial Research Project(Contract Number〔2014〕3018), Guizhou Provincial College Special Engineering center for Materials Protection of Wear and Corrosion , College of Chemistry and Materials Engineering, Guiyang University Project(KY[2012]023) References [1]Chen Qi, Chen Ya-wen, Kong Fan-ya.

On its basis the SAR number values for all investigated materials were calculated.
The SAR number values for the alumina matrix and composites.
The wear proceeded not only by the alumina grain crushing, but also by the weakening of grains boundaries and the removal of whole grains as a result.
In effect whole grains or grains agglomerates could be removed.
This counteracts rapid grain boundary erosion.

It seems that more constraints, which limited the number of nucleation sites and the selection of γ orientations, were involved in the formation of γ from pearlite.
The raw data were cleaned up using the grain dilation procedure in OIM with grain tolerance angle of 5o and minimum grain size of 5 pixels.
The number of new γ nuclei is 14, 28 and 39 at the time 0s, 180s and 240s, respectively.
Nucleation of γ does not take place uniformly and the nuclei number is relatively small at 990K.
The γ grain coarsening also takes places, as the small γ grains are consumed by the growth of the bigger grain.

Compared with scattered abrasive with the same number grains, the removal rate is less.
The number of cracked dings in the workpiece surface decreases and the surface roughness become little to a certain value.
The number of cracked dings in the workpiece surface is little, the roughness rapidly decreases and become nearly unchanged at last.
When the grain size is big, high speed is chosen.
Grain type and grain size of polishing film.

It is now well established that processing by ECAP has the capability of producing materials where there is a reasonably large number of grain boundaries having high-angle misorientations [12,13].
It is also apparent that the maximum elongation is displaced to a faster strain rate with increasing number of pressings from 6 to 8 passes where this is due to the higher fraction of high-angle grain boundaries that are anticipated in the sample processed to higher numbers of passes [13].
This procedure gave an ultrafine-grained structure with an average grain size of ~0.5 µm.
This procedure refined the grain structure to a grain size of ~0.8 µm.
By contrast, to date there are only a limited number of reports evaluating the role of grain boundary sliding in the ultrafine-grained materials processed by ECAP.

The carrier concentrations, hall mobilities and grain sizes of the AZO samples were measured.
Table 1 The test results of AZO samples number n[cm-3] μ [cm2V-1s-1] ρ[Ω·cm] Grain size[nm] 01 1.46×1019 1.407 3.03×10-1 28.5 02 2.23×1019 1.23 3.0×10-1 23.7 03 3.402×1019 5.076 3.615×10-2 65.4 04 4.837×1019 3.225 4.0×10-2 38.0 05 7.35×1019 3.5 2.19×10-2 60.0 06 8.42×1019 4.17 1.5×10-2 58.5 07 2.65×1020 3.1 7.6×10-3 81.8 08 4.34×1020 2.03 6.34×10-3 85.3 09 5.63×1020 1.47 8.08×10-3 80.8 10 7.82×1020 1.32 9.2×10-3 81.5 11 8.06×1020 1.25 9.45×10-3 54.6 The effect of the carrier concentration on the hall mobility.
In addition, even if a small amount of carriers arrived to the grain boundaries, they would pass through the grain boundary barrier because of the quantum tunnelling effect, so the influence of grain boundary scattering on carrier mobility was very small.
The grain boundary scattering and ionized impurity scattering coexisted for when the carrier concentration was a magnitude of 1019 for the samples ( number 01-05).
The carrier mobilities increased with the grain sizes increasing and the carrier concentration decreasing.