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Many previous studies were isothermal experiments performed using laboratory equipment for a limited number of temperature values.
The main assumption is that grain-growth arises via GB (grain-boundary) motion and that the driving force is represented by an inner pressure related to the GB curvature, therefore inverse proportional to the average grain-size G.
During continuous heating, a two-stage normal grain growth behaviour dominated by grain boundary diffusion was also evidenced for Agdoped specimens (Fig. 8).
The grain growth behaviour during isothermal annealing follows the grain-size dependent GB pinning model (Fig. 9).
Normal grain growth governed by grain boundary diffusion is observed during constant rate heating, while a lockup effect caused by grain-size dependent grain boundary pinning occurs during isothermal annealing at high temperatures.

Grains.
In the sense of this conventional definition of steady-state deformation, the maximum deformation resistance in Fig. 3 is a steady-state (subscript ss) resistance of a material of a given grain structure with a grain size depending on the number of ECAP passes, i.e. on prestrain.
At ambient temperature, i.e. , and 10-3 s-1 the steady-state flow stress increases monotonically with increasing number of ECAP passes towards a constant final value  430 MPa that is reached for (Fig. 3).
While the model is not altogether satisfactory, because it rests on empirical data for the steady-state spacings, it contains a number of observed features of deformation and can be fitted to measured data without losing important microstructural aspects.
Grain coarsening towards the steady state.

Therefore, the number of segregating impurities or solutes at the grain boundaries is less than in the case of structure that does not contain subgrains [5,6].
As can be seen, the grain boundary is also enriched in a network of grain boundary precipitates.
This is similar to the grain boundary precipitation of standard 5083AA.
the grain boundaries and hence intergranular corrosion.
Addition of Zn kept precipitation inside the grains, which results in grain boundaries free from precipitate.

Grain Boundary Diffusion and Grain Boundary Segregation in Metals and Alloys.
We name only a small number of the recent titles: I.Kaur, Y.Mishin, W.Gust “Fundamentals of Grain and Interphase Boundary Diffusion”[1], I.Kaur, W.Gust, I.Kozma “Handbook of Grain and Interphase Boundary Diffusion” [2], the review articles of Y.
Grain boundary self-diffusion 2.1 Fisher model.
Grain boundary heterodiffusion 3.1.
It was shown that the Fe-Fe coordination number is close to 1, which is much more than in a random solution.

Some particles, observed at grain boundaries and inside grains, are oxide phases [12].
Effect of the number of ECAP passes on mechanical properties of billets out of Grade 2 Ti.
Grain/subgrain size is reduced to 150-250 nm.
At the next stage of TMT the grain structure with a mean grain size of 100 nm in the cross section is formed with the total accumulated strain of 80% (Fig. 5 a).
The preliminary treatment allowed to reduce the number of ECAP passes, to enhance structure homogeneity and stability of mechanical properties, which, in turn, increased billet quality.

The IGC-susceptibility was related to a nanoscale Cu-rich film along the grain boundaries, along with coarse Cu-containing precipitates at the grain boundaries.
These precipitates along with the Cu film along the grain boundary are believed to contribute to the cathodic activity as grain boundary attack proceeds.
The segregation of Cu at the grain boundaries, gives us reason to assume solute depletion adjacent to the boundaries, making this area anodic to grain bodies and grain boundaries.
The adjacent zone, which must be depleted in Cu, is active compared to the grain bodies and grain boundaries and is therefore susceptible to knife line IGC.
Upon further artificial ageing, the grain boundary precipitates grow in number and size as a result of further precipitation and disruption of the continuity of the Cu-rich grain boundary film.

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.

Harvesting grain directly has been the development trend of modern maize combine harvester.
The type of most maize harvester in our country is self-propelled maize harvester or mounted maize harvester, which efficiency is lower than the foreign [1].The technique of plucking, threshing, separating, cleaning and gathering is used in a little number of maize combine harvesters, whilst it also has some problem.
After threshing and separating, maize grain falls to the cleaning device through concave grate.
When cleaning grain is completed, it fall to spiral conveyer at the bottom of the harvester, then it is transported to grain container by lifter.
Meanwhile, the grain fell to the cleaning device through concave grate.

The mechanical properties of ultrafine grained Al 6061 alloys were measured by hardness and tensile tests.
The number of rolling passes employed was 22 for the thickness reduction of 88% in the samples.
The microstructure exhibits equiaxed grain morphology with an average grain size of 70μm.
Heavily diffused and ill-defined non-equilibrium grain boundaries are seen in the microstructure.
However, only few grains are observed with clear grain boundaries, within the range of 200 to 600nm.

I"TRODUCTIO" The capacitance of multilayer ceramic capacitors (MLCCs) can be increased by decreasing the thickness of their dielectric layers and increasing the number of dielectric layers; however, these changes result in low insulation resistance (IR).
BaTiO3-based ceramics also include large grains with grain sizes of approximately 500 nm.
Presence of large grains in dielectric layers The regions with the smaller number of the grain boundaries per dielectric layer are formed due to the presence of large grains.
The number of grains between the electrodes is 4 and 6 in the samples with the 0.8- and 1.2-µm-thick dielectric layers, respectively.
On the other hand, the characteristics of grain boundaries is evaluated from the experimental result of the sample with the 1.8-µm-thick dielectric layer, assuming electric field at the grain boundaries is proportional to the ratio given by (dielectric layer thickness)/(grain boundary width × number of grain boundaries).