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Such a determination of the diffusion mechanism is by all means quite primitive, because in a number of publications (see, for instance, [11]) it was shown that grain-boundary diffusion can be realized by very complicated mechanisms of jumps of the diffusing atoms.
Numbers denote spectrum components The high-temperature section of the plots shown in fig. 2 corresponds to the beginning of the Mössbauer atoms pumping from grain-boundaries into the volume.
Emission 57Co( 57Fe) spectra of HPT W annealed at various temperatures Numbers denote spectrum components Table 1.
At heating up to 6000 С small grain sizes are retained but recovery proceeds, and grain boundaries get straighter and thinner while grains proper depurate of dislocations.
A decreased electron density on the Mössbauer isotope nuclei in near-boundary areas was also observed in a number of polycrystalline metals in [3,4], and this effect was attributed to the presence of interstitials segregation in these areas.

Since Grain yield prediction is significant for regulating grain prices, the research on the accurate prediction of grain output has great value.
The meaning of Markov transition probabilities )(mpij are: System consists of state i transferred to the system state j of the transition probability )(mpij only depends on the time interval m (step number) of the length of time, and has nothing to do with the starting.
(2) Division of the state Using (k)Yˆ curve as a benchmark, according to the specific circumstances of each prediction object is divided into a number of parallel bar area, each bar area to form a state.
Case study 1.Grain Output In Jiangsu Province According to Statistical Yearbook of Jiangsu Province, the main grain production show in Table 1.
The exact prediction of grain output has positive function for provide prevention and cure grain failure and regulate and control grain prices.

Then, the authors have been studied about the strength of thin wires of ferrous and aluminum alloys, and found that the scatter comes from the number of crystal grains in the cross-section because strength is affected by the orientation of the crystal grains [1, 2].
where n is the number of pass, F (rad) is the channel-intersection angle, and Y (rad) is the angle of curvature at the outer point of intersection of the two channels.
The S-N curves for thin plates are shown in Fig. 8, where arrows indicate that fatigue tests were terminated at this number of cycles.
ECAP method is superior because UFG can be made by less number of pass
Nakai, Kobe University), and Grant-in-Aid for Scientific Research (A) by the Japan Society for the Promotion of Science under proposal number of 24246024 (Head investigator: Professor T.

The effect of number of deposited layers on the grain size and surface morphology has been investigated using an atomic force microscope in contact mode.
The relation between the value of grain size and number of deposited layers is plotted in Fig. 2.
It can be observed that the grain size increases as the number of deposited BGT layers increase.
Figure 2: Variation of grain size with different number of deposited layers of BGT.
Using the same theory, the decrease in the surface roughness with number of deposited layers increment can be attributed to the gradual disappearance of the agglomerated grain regions as the number of deposited layers increase to appear as individual grains for four layers sample as it discussed earlier in Fig. 1.

Sulphides may show a different value of the contact angle within individual grains, which is probably caused by heterogeneity of particles [7].
Each sample was grinded on a LaboPol-21 grinder (Struers, USA) by a rotating abrasive paper with a grit size of 600, 800, 1200 and 2500 (number of grains per inch) under running water, followed by polishing on a Phoenix 3000 (Buehler, USA) by a fine textile polishing cloth using aluminum paste without ultrasonic cleaning of the surface after each step.
Compared to the other pyrite samples, the areas of pyrite grains were much smaller and surrounded by other minerals.
The number of outliers, arithmetic mean and standard deviation for each deposit is given in Table 2.
The number of outliers in the whole set for a given type of genesis deposit did not exceed 4%.

The results indicated that the hardening behavior of fine grained samples (mean grain sizes in the range of 2.13.8µm) can be described as typical dislocation interactions.
However in coarse grained samples (mean grain sizes in the range of 4.7-38.5µm) where extensive mechanical twinning occurs, another strengthening mechanism is required.
The number of dislocations in the pile-up is related to the resolved shear stress in the slip plane and the distance between the source and the obstacle.
Therefore in coarse grained samples, the operation of primary slip systems during the initial stages of deformation and the formation of an appropriate number of dislocations in the pile-up result in continued plastic deformation with minimum slip systems.
Conversely in the case of fine grained samples (for example with a mean grain size of 2.1µm), since the mean grain size is not sufficient to create the appropriate number of dislocations in pile-up from primary slip systems, secondary slip systems start operating.

The grain boundary diffusion strongly depends on the grain boundary character and structure [1].
The GBCD was shown by the fraction of number of grain boundaries with specific S-value.
Figure 3 shows the change in the average grain size of {111} grains and other grains in gold thin film specimens during annealing at 873 K.
The average grain size of {111} grains became modestly larger than that of the other grains.
The percolation probability is evaluated by the ratio of the maximum number of percolation-susceptible triple junctions connected by random boundaries to the total number of triple junctions.

Nanocrystalline materials consisting of nanometer-sized crystallites contain a large number of interfaces, i.e.
Such nanocrystalline electrodeposits are in a high non-equilibrium (metastable) state, i.e. a high energy state due to a large number of interfaces [8, 9].
Journal Title and Volume Number (to be inserted by the publisher) 3 Table 1.
The fronts of the abnoramlly growing Journal Title and Volume Number (to be inserted by the publisher) 5 grains are observed to be not smooth and to consist of individual segments having different misorientations with the adjacent nanostructured matrix.
The fact that the <111>//ND grains are much coarser than the <100>//ND grains in the fully annealed specimen is attributed to the abnormal grain growth of the former in the early stages of grain growth.

The legend indicates the number of grains in the RVE.
Total number of grains distributed over the mesh Average number of grains within each RVE Number of time steps Computing time 25000 5 400 3 h 100000 20 280 5 h 200000 40 290 9 h 500000 100 280 20 h Table 1 Description of deep-drawing simulations performed with reduced grain samplings.
Every element has 8 integration points and the average number of grains in each RVE is given in the legend.
The average number of grains within every one of the 40 RVE is indicated in the legend.
The average number of grains within every one of the 40 RVE is indicated in the legend.

And the pulling velocity should be controlled less than 0.5 mm/s in our experiment so as to effectively decrease the grain number and mean grain deviation.
Fig. 4 (b) shows the influence of pulling velocity on the grain number and mean grain deviations at the cross section of z=0.45 m.
The grain numbers fluctuate at 35 and mean grain deviations fluctuate at 15° with the range of pulling velocity from 0.1 mm/s to 0.4 mm/s.
Since fewer grain number and mean grain deviation are pursued, the pulling velocity should be controlled less than 0.5 mm/s in our experiment.
And the grain number decreases and the grain transverse size increases with increasing distance from the bottom surface of the casting.