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This microstructure evolution is also be supported by the corresponding SAD pattern that changed from single crystal type to polycrystalline type with increasing pass number of CCDP substantiating grain refinement and increasing misorientation across the grain/subgrain boundaries, as evident from the TEM micrographs and SAD patterns in Fig. 3a-d for 1, 4, 8 and 16 passes of CCDP, respectively.
After that the grain size didn't decrease any further, but grain boundary misorientation increased steadily with the number of CCDP passes (see the SAD patterns in Fig. 3-4).
Fig. 5: Mean grain size along the longitudinal direction of both alloys as evaluated from the grain size distributions of 700-1000 grains for each sample.
The strain softening becomes more pronounced as the number of CCDP pass increases (Fig. 6a).
Fig. 8: Microstructure of Al-1.5Mn and Al5Zn-1.6Mg alloys after large number passes of CCDP.

Increase in amplitude dependent damping in ultrafine-grained copper is due to dislocation but not grain boundary contribution.
There is a set of non-equivalent energy positions for atoms and grain boundary dislocations in grain boundaries, which results in the existence of a relaxation times spectrum.
Grain size is also indicated for several temperatures in Fig. 3b.
The analysis of IF experimental data [8] gives value k = 1.3, which is close to k = 1.14, obtained in [4], and suggests growth of new grains on the GB of deformed grains.
At ε0 > 2.5×10-4 values of IF depend on number of cycling, see arrow from n.1 to n.7 cycle.

Table 1 Heat treatment technology for specimens Number Quenching temperature Holding time（h） Number Quenching temperature Holding time （h） 1 850℃ 0.5 17 780℃ 0.5 2 850℃ 1.0 18 780℃ 1.0 3 850℃ 1.5 19 780℃ 1.5 4 850℃ 2.0 20 780℃ 2.0 5 820℃ 0.5 21 750℃ 0.5 6 820℃ 1.0 22 750℃ 1.0 7 820℃ 1.5 23 750℃ 1.5 8 820℃ 2.0 24 750℃ 2.0 9 850℃ 0.5 25 780℃ 0.5 10 850℃ 1.0 26 780℃ 1.0 11 850℃ 1.5 27 780℃ 1.5 12 850℃ 2.0 28 780℃ 2.0 13 820℃ 0.5 29 750℃ 0.5 14 820℃ 1.0 30 750℃ 1.0 15 820℃ 1.5 31 750℃ 1.5 16 820℃ 2.0 32 750℃ 2.0 Results and Discussion Microstructure.
That’s because the ferrites grains would block the growth of austenite.
The grain size of austenite grew up severely when holding time is 2h.
So the grain size in 850℃ grew very clearly.
(2) The grain grow up continuously with the increasing of holding time

The apparent nucleation density (i.e. the number of grains/mm 2) increases with straining.
It is expected that deformation at 700ºC activates a greater number of small nucleation sites than at 740ºC.
The size of ferrite grains varied from 0.2 to 3 µm.
A significant number of iron carbides was observed within the microstructure.
From these micrographs, it could be seen how the growth of new grains is restricted by a significant number of cementite particles surrounding them.

The number of triple junctions in polycrystals is comparable in the order of magnitude with the number of boundaries.
Scheme of the grain boundary system with a triple junction, a - width of the middle grain; 2θ - value of the vertex.
GB I GB III Grain 3 Grain 2 Grain 1 GB II 2θ θ a/2 a/2 θ y x ϕ v V GB III GB II GB I Experimental The experiments were carried out on tricrystals of high purity (99,999%) aluminium with a grain boundary geometry as shown in Fig. 1.
The position of the grain boundary system and the angle θ were recorded from the grain boundary grooves.
The value of compensation temperature for the grain boundary with triple junction systems and individual tilt grain boundaries in Al are given in the Table 2.

Grain drying is an important part for the safe storage of grain.
For the safe storage of grain, it is an important step to reduce grain moisture with the help of grain drier [1].
The online detection system of grain moisture consists of the host controller (central controller) and two online remote module of grain moisture detection (grain ingoing module and grain outgoing module).
If the host machine does not receive this parameter, it will attempt to resend 0x01, once it exceeds the number of retrying, the system will automatically skip this test and give an alarm.
There are 5 reasons for random error: (1) The number of grain sample is only 39 rice particles, thus it is not enough to stand for the average moisture content of grain within this period; (2) The distribution of moisture in the original grain that bought by the drying center is asymmetrical, which enhances the error for the test data of ingoing grain; (3) There are a modicum of snow and ice in the original grain, which influences the test result of ingoing grain; (4) The uniformity of drying machine to grain will influence the test accuracy of outgoing grain to some extent.

On the other hand, the number of research works as to SPD of commercial medium carbon steels is still limited [6], because SPD processing is relatively difficult in steels with higher flow stress.
Grains of pearlite with size of ~ 50 μm are lined by the finer ferrite grains (~10 μm in diameter).
These pearlite grains are lined by finer ferrite grains, Fig. 1a.
Finishing ECAP deformation the corresponding effective strain in dependence of number of passes was εef = 2.7, 3.4 and 4 respectively for individual samples.
The deformed microstructure, which resulted from different ECAP straining of steel, related to different number of passes through die channel 500 nm (N= 4 and N= 6 passes) is presented in Fig. 4.

Effect of Addition of Some Grain Refiners to Zinc-Aluminum 22, ZA22, Alloy on its Grain Size, Mechanical Characteristics in the Cast and after Pressing by the Equal Channel Angular Pressing, ECAP Adnan I.
Zr has adverse effect on grain refining efficiency resulting in a coarse grain size.
Multi-pass ECAP process to investigate strength, hardness and ductility of commercially used zinc- aluminum alloy (ZA-12) as function of both the applied load and the number of passes was investigated in [9].
The prepared samples were subjected to 1 to 4 pressing then sectioned for examination, it was noted that pressing of Al samples led to the development of the parallel bands of sub-grains and these sub-grains subsequently evolve with further pressing into an array of grains separated by high angle grain boundaries, [10,11].
Effect of the grain refiners on ZA22 micro-hardness.

These simulation results can not only be used in artificial controlling the grain boundary of nano-grain, but also is of significant for designing new nano-grain with a good grain boundary for structure materials.
Its grain growth and grain volume distribution have a great influence on properties of materials [1].
Results and analysis A number of metals are of Fcc structure, for example, Al, Cu, Au, Ag metals.
Turn to look the grain I and grain II, although the grain boundary between the two grains look like coherence, it still have chink.
The simulation results can be used in artificial controlling the grain boundary of nano-grain and is of significant for designing new nano-grain with a good grain boundary for structure materials.

A comparison with pure Cu shows that the grain size homogenization is shifted towards higher number of ECAP passes.
Depending upon the processing regimes ECAP may influence the microstructure in a number of significant ways.
The total number of indentation prints in each sample was around 130.
%Co solid solution is shifted towards higher number of ECAP passes [5,6].
A comparison with pure Cu shows that the grain size homogenization is shifted towards higher number of ECAP passes.