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Grain size, texture and strain rate jointly affect the deformation mechanisms.
The lowest processing temperature was 388K, and the average grain size was ~370 nm.
reason that the fine grain had just began to generate around the coarse grain due to severe plastic deformation of ECAP progress.
What’s more, finer grain size leads to more grain boundaries which will block the move of the dislocation as slip metamorphosing and that will increase the resistance of plastic deformation.
The average misorientation angle increases as the increase of the pass number and that will result in the easy appearance of extension twinning under compression load.

The anisotropic properties of grain boundary energy and grain boundary mobility were expressed as functions of grain boundary misorientations.
Each lattice site is assigned as a number, Si, which corresponds to the orientation of the subgrain in which it is embedded.
The number of distinct subgrain orientations is dependent on the measuring step size and area.
The total number of subgrains is 18537, which is a reasonable number to simulate primary recrystallization using MC technique.
It should be noted that just a few recrystallized grains remained after the competition with neighboring grains.

Study on the evaluation of minor rural road network planning alternative in the state commercial grain base Hongjiang Gao1, a, Zhenni Pan1,b Siling Yang1,c 1School of management Tianjin University Tianjin, China aghj-751018@163.com, bzhenni-pan@163.com, cysl.20021077@163.com Keywords: the minor rural road planning; road network evaluation index; fuzzy entropy weight; double base method ; the state commercial grain base roads Abstract.
Introduction The state commercial grain bases is a basic form of the agricultural areas division system, and the agricultural professional area, the function of which is grain production primarily and providing commodity grain and other related agricultural products for social and economic development [1].
(2) Where is the road network connection degree, the total number of road network node; the adjacent edge number of the No.i node.
Patch density, patch number, patch area and so on, all affect the rural landscape fragmentation
(7) Where, is the total number of the cultivated land patches, the average area of the cultivated land patch.

Introduction Nanostructured (ns) and ultra fine-grained materials exhibit higher strength and hardness, as well as excellent tribological properties compared to their coarse grained counterparts [1, 2].
Mishra et al. [6] compared the fretting behaviour of ns Ni (grain size of 8 nm) prepared by means of electrodeposition with that of bulk coarse grained polycrystalline Ni (grain size of 61 μm).
A gradient in microstructure i.e. finer grains in the surface and near surface regions and coarse grains in the bulk may be seen.
Figure 6 shows the variation of TFC with the number of fretting cycles for untreated and treated samples at 4.9 N normal load.
They reported that at a particular grain size (32 nm) the wear resistance was maximum and grain sizes above and below this size resulted in poor wear resistance.

studied carefully the hardness of the alloy during aging and revealed the existence of softer regions near the surface and the grain boundary than the interior of the grain even after aging for a long time [1].
Specimens for hardness test, 10x50x1mm 3, were strain annealed for the grains to grow to about 5mm in average diameter.
Fig.3 (a) shows the hardness number measured at 0.25 to 98N of load when the various thickness of surface layer was removed by electropolishing for the binary alloy specimen aged for 120ks at 293K after quenching from 623K.
When no surface layer is removed (as aged), hardness number decreases with decreasing load less than 9.8N.
If the specimen was homogeneous in hardness from the surface inward, hardness number would not show the dependence on the load, which has been confirmed by measuring a reference specimen [1].

The number of the acid centers of the carrier fixed loading became larger and the combination turned more firm.
Analysis of specific surface area, grain size and sulphur content .
The average grain size of the catalyst SZ samples was 148 nm and the average grain size of the catalyst SZ-C samples was 99 nm.
The smaller the grain size, the larger the specific surface area of the catalyst with the same mass, the more the number of the acid centers, the higher the catalytic activity.
While the grain size of the catalyst SZ-C was small and even.

Size of microvoids deduced from τ2 is represented in the last column as corresponding number of vacancies nV (see text for details).
grain interiors, was found by TEM in UFG Cu and Fe as well.
A large number of vacancies is created during SPD.
Microvoids (small vacancy clusters) are formed inside grains.
Number of defects in HPT deformed sample decreases with depth in certain surface layer.

Influence of Nanoparticle Reinforcement on the Mechanical Properties of Ultrafine-Grained Aluminium Produced by ARB Christian W.
The so-produced composite material showed about 17 % higher tensile strength than unreinforced aluminium after the same number of ARB cycles.
With this method a strengthening of 12.6 % related to the unreinforced reference condition after the same number of ARB cycles was achieved.
The additional strengthening was reported to reach up to 12.6 % and was shown to be caused by additional plastic strain around the hard embedded nanoparticles leading to an acceleration of microstructural evolution in the first ARB cycles as well as reduced grain sizes after a high number of ARB cycles.
The grains are clearly elongated in rolling direction (RD) and have a median grain size in the range of 0.4 µm.

The main reason for low ductility is associated with an insufficient number of deformation systems, activated at these temperatures due to the hexagonal crystal lattice type of the alloys with a high ratio c / a.
The average grain size also depends on the routes and modes of ECAP and generally decreases with increasing total strain due to increase in the number of passes.
Types of grain boundaries.
Grain refinement during ECAP is the result of activation of large shear deformation and dynamic recovery and recrystallization behavior, and with increasing of the number of passes low angle boundaries (LAGBs)of the formed small subgrains rotate relative to each other and adsorb a large number of dislocations, becoming the non-equilibrium high-angle grain boundaries (HAGBs)[10,11].
At relatively high temperature deformation of ECAP preferential formation of HAGBs can occur and at the small number of passes [12].

The situation can become fast impossible to manage, especially for some rolling processes, which involve high number of passes 2) Both families of grains generated at the end of each pass can be merged into just one family, with a weighted average grain size according to the respective fraction of recrystallized and strain hardened grains.
This methodology cannot be applied for superalloys: generation of new grains involves significantly higher strain values [5]. 3) Between these two extreme approaches, specific treatments of microstructures obtained after each pass can be undertaken, in order to reduce the number of grain families we have to manage, without coming up to just one family as specified above.
Related to the processing of strain hardened grains and considering the same example as above, Figure 3 shows the comparison between the calculated and measured recrystallized fraction Xtot as a function of number passes.
For instance, it is possible to calculate the number of recrystallization sequences during the process.
Microstructure appears fully recrystallized with a homogenous grain size even if computation leads to a decimal number for the recrystallization fraction.