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As for the morphology of grain size, it was not homogeneous, small and big grains were in the specimen together.
The grain size of the as-ECAPed specimen was almost under 200 nm.
Further, although many small grains under 200 nm remained, annealing up to 550 o C increased the number fraction of grain size over 200 nm.
Histograms of grain diameter.
Annealing changed grain sizes of the specimens, the grain size of the 600 o C annealing specimen also became the largest of all annealed specimen.

According to our research, we conclude that, the existence of a large number of twin, twin boundary, fault and the grow up grain are the main factor of the improvement of the electrical performance; and the existence of twin, stress concentration holes and fault are the key to improve its mechanical properties.
Also, we observed the grain growth phenomenon.
It clearly shows the quasi-static grain.
A large number of vacancy defects form in the process of atomic plane slip.
After LSP, the hardness and elastic modulus of the nanometer copper film increase by 38.5 %, 45.2 %, respectively; 2) The existence of a large number of twin, twin boundary, fault and the grain growing up are the main factor of the improvement of the electrical performance.

Mg17Al12 is formed as discontinuous precipitates at grain boundaries, which might promote the grain boundary sliding during elevated temperature applications [3].
One effective way to hinder the migration and sliding of grain boundaries at elevated temperature is to form strong precipitates with high melting points at the grain boundaries as well as at the grain interior.
Generally, Mg2Sn precipitates forms both at the grain boundaries and at grain interior during aging.
The general idea of increasing the strength is by increasing the number density of particles, i.e. increase in precipitate nucleation rate.
It is clear that the number density and the vol. % precipitate increase with increasing aging time.

The Study on used Properties of Mine Tailings Sand Gang Li1, a, YingJie Chen2,b and Hao Di3,c 1State Key Laboratory of Ministry of Education of China for High Efficient Mining and Safety of Metal Mine , University of Science and Technology Beijing, Beijing 100083, China 1Shenkan Qinhuangdao Engineering & Technical Corporation MCC, Qinhuangdao 066001, China 2,3Department of Civil Engineering and Mechanics,yanshan University,Qinhuangdao aemail:ligang0504@126.com, bemail:cyjysu@126.com, cemail:dihaohaodi@126.com Keywords: mine tailings;gradation of grain;compressive strength;loss on ignition Abstract: Nowadays,there are a large number of mining tailings in China,ore tailings not only pollute the environment,but also consume plenty of land resources,even threat the safety of people's life.In this article ,researches have been done to gradation of grain of tailings in QinHuangdao by the test,and compressive strength and loss on ignition with different volume of tailing concrete.
Messive discharge of tailings accumulation not only occupy the land ,causing environmental pollution, and poorly designed tailings dam collapse will result in casualties, at the same time, tailings transportation emissions requires a large number of mechanical equipment and power facilities.
In the early eighteen sixties,the Soviet Union began studying and producing building materials using tailings , such as the Krivoy Rog iron ore in tailings proper graded as aggregate , with fine grained tailings production silicate building products.
Table l Tailing grain-size composition analysis table of Miaogou Iron ore Mesh Particle size (mm) Yield（%） Cumulative yield（%） 80 +2 4.07 4.07 100 -2～+1.5 5.98 10.05 140 -1.5～+0.10 5.80 15.85 200 -0.10～+0.076 10.20 26.05 280 -0.076～+0.055 16.22 42.27 350 -0.055～+0.042 4.19 46.46 400 -0.042～+0.03 10.80 57.26 — -0.03～+0.02 9.15 66.41 — -0.02～+0.01 6.22 72.63 — -0.01 27.37 100.00 Particle density of Miaogou tailings is 2.85 t/m3, pulp density is 40% of tailings, tailings average particle size is 0.056mm,out of which -200 mesh accounted for 74% of, -400 mesh 50%.
Table 2 Tailing grain-size analysis table of Cherry blossoms Iron ore Grain（mm） +0.074 -0.074～+0.056 -0.056～+0.037 -0.037～+0.019 -0.019 Yield（%） 31.04 19.47 17.04 14.60 17.85 The average particle size of Luan County cherry tailings is 0.0978mm, tailings median particle size is 0.028mm.

In this study, appearances of grain interior strain localizations are related to the number of grain interior high angle boundaries: as estimated by EBSD.
The dislocation density increases linearly with increase in number of grain interior strain localizations for both g and q fibres (Fig. 3).
Fig. 2: Number of grain interior high angle boundaries as a function of temperature and strain rate.
Fig. 3: Dislocation density as a function of number of grain interior high angle boundaries.
Fig. 4: X-ray resolution function as a function of number of grain interior high angle boundaries.

Grain size in brass scatters from 10 to 200 µm.
The increase of number of various facets roughly correlates with decreasing grain size.
In case of twin GBs each 3 rd lattice site of a grain 1 coincides with a lattice site of a grain 2, and Σ = 3.
It can be seen that the number of crystallographically different facets increases with decreasing temperature.
Indeed, it can be seen from the Table 1, that the number of various facets is really larger in samples where the grain size is lower.

Z is the average number of atoms per unit area at the grain boundary.
N is Avogadro’s number. h is Planck’s constant.
N1 is the site number of matrix phase.
N2 is the site number of liquid phase.
(10) where is the arithmetic average grain radius, NTol is the total number of site in the simulation domain, A0 is the area of site and NGrain is the total number of grain in the simulation domain.

Grain growth.
The discretized grains are used for the calculation of the mean grain size, µ, and the grain size distribution in the form of standard deviation, σ.
Systematic errors are often an issue, and for the complicated field of temperature measurements there was a feeling that this field would be no exception dealing with emission numbers, wall temperatures, surface temperatures etc.
The results reliability improves as the number of coils fed into the ANN are increased and the model results are very dependent upon accurate temperature measurements and that this is a complicated field, especially for stainless steel and aluminum where emission numbers can be difficult, the RMS error is low and model accuracy is high.
Since the model discretization deals with time steps and not with individual grains, each time step represents the average grain size for this time increment and the grain growth is the increase of average grain size for the time increment and not for the individual grain.

This method can be subsequently used to produce refined grains in the sub-micrometer range [2, 3].
The strain in-homogeneity is low at 120° but the strain imposed is not sufficient to produce ultrafine grains and require more number of passes to achieve the maximum strain.
The load required for the channel angle of 120° is low but the strain imparted is very low such that it requires more number of passes to achieve maximum strain
· The effective strain, effective stress and peak load increases as the number of passes increases
Using equal channel angular pressing for refining grain size.

The crystal orientation obtained for each grain was used to estimate elastic constants of grains with an fcc structure.
Typically, the strain is large in grain E while it is small in grain A, as shown in Fig. 5 (c).
In other words, Young’s modulus is low in [100] oriented grains, and it is high in [111] oriented grains.
The grain images of the unloaded and tensile-loaded sample were obtained though the analysis of a large number of Laue patterns.
For instance, it is known that a large number of heterogeneous dislocations, which are called with geometrically necessary dislocations [9], are generated close to interfaces such as grain boundaries and twin boundaries.