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In work [8] on pure α-Fe (99.95 wt.%), a nanostructured layer with a large number of deformation defects was formed by the surface mechanical attrition treatment (SMAT) as pre-treatment.
CRA-regime resulted to the formation of a coarse-grained structure with an average grain size of d=70±18 μm in size.
Grain-subgrain structure, CR-regime Coarse-grained structure, CRA-regime Fig. 1.
Ion-plasma treatment produces the composite layers on the side surfaces of 316L steel samples with both grain-subgrain and coarse-grained structures.
For both fine grain-subgrain and coarse-grained samples, the composite layers possess high values of nanohardness.

EBSD results suggest that the mean number of twins per grain saturate rapidly, followed by the stop of twin growth.
We use electron backscatter diffraction (EBSD) to determine whether the twin volume fraction or the mean twin number per grain can saturate, and we elaborate the effects of twinning saturation on pure twin hardening, employing the modeling of a mean twin number.
Nt is the mean twin number per grain, d is the mean grain size.
Nt is defined as Nt=nt/ng, nt is the total number of twins, and ng is the total number of grains. e is defined as e=et/nt, with et being the total thickness of all twins.
ε=0.0015 ε=0.015, T1 ε=0.065, T2 ε=0.02 Fig.2 Mean twin number per grain vs. true strain Conclusion The mean twin number per grain Nt reached its saturated value rapidly, and after that the growth of twins also stopped.

It is generally known that the breakdown electrical field EB can be expressed by the following equation [9,10]: EB = n•Vgb, (1) where n is the average grain number per unit length, Vgb is the breakdown voltage of one grain boundary of SnO2 ceramics.
Whereas, the increase of EB for SCTI is related not only to the grain size, but also to the breakdown voltage of one grain boundary Vgb.
That is, the electric charge states of defects on the grain boundary should be affected greatly by doping In2O3 considering that the grain boundary barrier has great relation with defect states.
In this study, the presence of Schottky barrier is inferred from the good linear agreement of ln(J/AT2)-E1/2 curves (Fig. 3) and the barrier height is obtained from the following relationship: , (2) where A is Richardson constant, kB is Boltzman constant, E is electrical field, and β is a constant in reverse proportional to barrier width ω and grain number per unit length n.
Thus, it is reasonable to suppose that some compoundsubstance including yttrium may locate at grain boundaries to hinder the combination of SnO2 grains.

This method introduces three-dimensional compression and shear stresses and the process can be repeated for a certain number of passes until the desired accumulated strain has been introduced.
The present work investigates the effects of both particle numbers and the type of particles on the microstructure development.
Also, in alloy AZ31-1Si the grain size distribution exhibited a bimodal nature although the coarse grains dominated over the finer grains (Fig. 2b).
These observations indicate that additional alloying in the AZ31 alloy system do not increase the number fraction of fine grains, hence larger amounts of second phase particles seemed to promote less bimodality.
(4) The grain size, grain shape and grain boundary structures in the present alloys seemed to be little affected by the coarse phase Mg2Si.

Fabrication and Cutting Performance of Ultrafine Grain Composite Diamond Coated Drills Y.P.
The wear of drills is evaluated by the number of holes machined successfully and the cutting length.
The grains are relatively large; the average size is about 6µm.
Broadening of the diamond band is a result of the decrease in grain size and phase purity.
(a) Uncoated drill ;(b) microcrystalline diamond; (c) ultrafine grain/microcrystalline diamond.

In consideration of the number of filler materials currently available, it is necessary to be able to sort these components well and use them optimally.
The results of the larger magnification of specimen 1 were misrepresented, as there is also a very large number of small particles in the specimen.
In contrary, the last specimen (number 6) with the smallest grains has a larger magnification (149 x 149 μm area).
An important aspect in the measurement is whether the grain volume or the number of grains is considered.
Fig. 4 Size and shape characteristic by grain volume Fig. 5 Size and shape characteristic by number of grain Figures 4 and 5 shows the arithmetic means of the measured values.

Introduction As demonstrated in a number of recent publications, grain boundaries in submicro- and nanocrystalline materials obtained by severe plastic deformation (SPD) are non-equilibrium and considerably differ from the grain boundaries of recrystallization origin in conventional polycrystals [1,2].
After the 7000С annealing the abnormal grain growth was observed in some areas and very coarse dislocation free grains surrounded by much smaller crystallites appeared in the structure.
The line with the higher isomer shift (component 1) corresponds to the Mössbauer atoms located in grain boundaries, and it is referred to as the grain-boundary line.
First of all, they could result from migration of grain boundaries.
Grain growth in central areas starts at 10000С, and in the periphery at 7500C.

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.

The structure of grains is defined by vertices with positions kr r where Nk ..1= (N - number of vertices in the structure).
The unit of time is defined as one Monte Carlo Step (MCS), which corresponds to N trials of position change for chosen vertices, where N is the total number of vertices in a map.
Such kind of behavior was observed in simulations obtained with the presented model (Fig. 3). 1000 2000 3000 4000 1000 2000 3000 4000 5000 6000 7000 8000 MCS Fig. 3 Plot of grain growth kinetics (average size of grains in function of time - MCS) 1,5 2 2,5 3 3,52,5 3 3,5 4 4,5 log(1+t) log N Fig. 4 Evolution of the grain number in time.
The circles define the linear region for which the slope defines grain growth exponent λ Number of grains N is also time dependent and obeys the following equation [11]: ( ) ( ) λ2 0 10 −       += t t NtN (6) This relation can be represented in a log-log plot in which the grain growth exponent λ determines the slope of the linear region.
In quite wide interval (number of grains changes from N=640 to 150) we can observe linear behavior for which the slope is -2λ = −0.93 ± 0.01, thus gives the grain exponent λ = 0.46 ± 0.01.

The grain size tends to be lowered as the ratio is close to the critical value.
The grain size was reduced from 50 µm to less 10 µm except at the center of the rod.
The grain size was reduced to ~1.5 µm and this fine-grained region covers from the outer edge to the region ~ 1 mm off the center.
It is apparent that grain refinement is effective when the STSP temperature is lower.
The former leads to insufficient numbers of dislocations to create grain boundaries and the later makes it difficult to keep the grain size small.