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Three different tendencies for the development of the volume fraction with increasing number of cycles were distinguished.
Cycling of one specimen was periodically interrupted at different number of cycles.
Then the fraction of grains containing PSBs (open triangles) grows continuously with increasing number of cycles.
Each line corresponds to the development of the volume fraction of cumulated PSBs with increasing number of cycles for an individual grain.
Therefore, the volume fraction of these grains is very low, even with increasing the number of cycles.

The large grains appeared with at least 4 - 5 sharp edges.
Each three or four grains are meeting together in one point.
The patches of the new Mo rich phase might be surrounded by large number of V"Zn.
The decrease of E0 with Mo content is attributed to the decrease in the number of active grain boundaries connected in series [15].
Fig. 6, (1/C - 1/2C0)2 vis the applied voltage V per grain boundary Table 1; Properties of the grain׳s boundary of Zinc Molybdenum ceramic; Sample number, Mo content, non linearity coefficient α, height of the interface potential barrier Ф (eV), donor density Nd, density Ns of the interface states, the width W (10 -6) cm of the depletion layer and The threshold electric field Eo(V/cm).

According to Ma et al., we characterize the misorientation field corresponding to an arbitrary distribution for grain boundary in system (2) where θij is the misorientation angle between grain i and grain j with orientationsηi and ηj.
The parameter K is a variable dependent on grain boundary energy., The grid sizeA time step for integration is.36 orientation The 36 number of field variables was chosen. 　
However inhomogeneous grain boundary migration rate affect grain boundary structure.
The at the later stage computed microstructure becomes heterogeneous which consists of large grains and small grains.
In in homogenous systems grain size distributions in simulated grain structures were binodal distributions.

The use of calculated parameters of grain size distributions is proposed to identify groups of grains by their origin.
However, detailed analysis with the possibility of grains division into groups according to their characteristics is of great interest since a number of competing processes may take place in a material under deformation, for example, by HPT, including various relaxation processes directly under deformation, after it or at following annealing [18-21].
Histograms of grain size distributions with approximation results: 1, 2 – groups of grains.
However, this approach requires more qualitative experimental data containing larger number of measurements.
Plasticity and grain boundary diffusion at small grain sizes, Adv.

Nomenclature rKth threshold stress intensity factor rKth(0) threshold stress intensity range at load ratio of zero rK0 hypothetical threshold stress intensity range at zero grain size kf fatigue notch factor ky material constant: hardening contribution from grain boundaries d grain diameter s0 yield strength with no grain boundaries sy yield stress L total test line length Va volume fraction of ferrite Na number of ferrite grains intercepted by the last line M magnification of the print W width of specimen a crack length a a/W rP applied load range (Pmax – Pmin) B thickness of specimen R stress ratio Introduction In order to accurately predict the fatigue lives of components, it is essential to consider the growth behavior of fatigue cracks at near threshold levels.
Left hand numbers represent the amount of rolling deformation, the center letters indicate the cooling medium applied (BQ=iced-brine quenched, HWQ=hot water quenched and OQ=oil quenched) and right hand numbers represent the intercritical annealing temperature.
Grain Size Measurement: Average grain size was measured from photomicrographs using mean linear intercept method.
Effect of ferrite grain size on ΔKth Table 1.
They showed that, although the yield stress became relatively insensitive to grain size, for coarse grain rKth increased as the grain size was increased.

Today is a lack of such data due to the limited number of the measuring methods.
The average grain size was 115 µm.
These data resemble the Shyshkovsky isotherm for a dilute solution [11] (2) where γ0 is the surface tension of pure solvent, γS is the surface (S) tension of solution, γGB is the grain boundary (GB) tension of solution, T is the temperature, R is the gas constant, z is the number of adsorption sites at the surface (grain boundary), b is the constant of adsorption equilibrium and c is the solute concentration in at. %.
It is possible to evaluate the number of sites in surface (grain boundary) monolayer A A m N N V n 3 2 max −       = , (3) where Vm is the solute molar volume and NA is the Avogadro number.
Experimental values of surface and grain boundary tension.

Many grain and oil depots have been established.
One group is composed by grain depots, oil depot, delicate railway and dock, deep processing for the grain and oil factory, test office.
Low load-carry ability of grain and oil depots construction.
The arrangement of sand drains are quincunx with diameter of 0.4 m ,distance between drains of 2.5 m ,length of 18m and the total number of sand drains is 283.
A large number of practical projects show that the ground bearing capacity of the region can improve 15 to 30 kPa by vacuum preloading method.

However, a good number are believed to originate from dislocation accumulation processes, during which the misorientation angle across certain strain-induced low angle boundaries (LAB) rises with increasing strain.
The grains of the pure Fe grade were even coarser.
Grain aspect ratio (AR).
Equiaxed grains were considered to have AR < 2. 4.
Secondly, the correlated distributions indicate a large number of LAB (practically 50 % of all detected boundaries) that are virtually absent in the uncorrelated plots; this clearly shows that the LAB are an important feature of the deformed microstructures and not merely the result of texture development.

MDF and microstructural evolution Figure 2 shows changes of flow stress with increasing pass number of MDF.
At a strain of = 0.4 (Figs. 3 (a), (d)), i.e. after the 1st pass of MDF, a numerous number of parallel lines appeared in grain interiors.
And the average grain size, d, can be calculated approximately by d = (DL/n)1/2 (2) where n the number of twins included in a packet [13].
Their finding implies, therefore, the important role of grain boundaries on UFG evolution during SPD, i.e., a favored grain refinement along the grain boundary.
Effect of grain boundary sliding becomes important for ductility even at room temperature when grain size becomes submicron order [20].

The first region provides the lattice diffusivity whilst the second or tail region provides (for self-diffusion) the product of the grain boundary width and the grain boundary diffusivity, i.e. δ Dgb.
The rest of the lattice represents the grains.
To simulate a thin-film (instantaneous) tracer source, 10 6-108 particles are created and released from the surface and allowed to diffuse for a time t (proportional to the number of jump attempts per particle).
These concentration profiles are built up simply by determining the number of particles that have reached a given distance from the tracer source plane after the diffusion time t [12].
Again, remarkably, this value seems to be independent on the grain size and ∆.