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Deviations from the macrostress on the scale of individual grains denoted as grain microstresses, arise as a consequence of differential deformation.
Results and discussion Residual ferrite grain microstress.
It is quantitatively different between particular grain families, but still following the same qualitative trend.
Thus, the recorded (grain) microstress saturation points to fully plastic deformation of (all {hkl} grain families of) both present constituents/phases in the pearlitic steel beyond the accumulated strain level εt ≥ 0.6.
The average residual ferrite phase microstresses were determined from the residual stress values recorded for the particular {hkl} lattice plane families (taking into account their multiplicity factor related to a number of equivalent scattering planes).

According to the dimensionality of grains or crystals, metals structure can be classified as follows: - coarse-grained (CG) structure - traditional engineering materials (dÎ<1;100) [μm]) - fine-grain structure (dÎ<10;1000) [nm]): ultra fine grain (UFG) (dÎ<100;1000) [nm]), nano crystalline (NC/ NG) structure (dÎ<10;100) [nm]).
Grain refinement.
Grain growth in FG metal materials.
The effective nucleation surface consists of increments from grain boundaries (gb) and deformation bands (db) which are described by following formula [19]: (4) With increasing of Sv(gb+db), a number of nuclei for the transformation from the austenite to the ferrite increases but on the other hand a diameter of the FGS decreases.
Grain rotation, grain boundary sliding and grain boundary diffusion are main plastic deformation mechanisms in SPD processed materials.

Grain refinement causes higher strength and better formability.
Their researches were, however, limited to the partial occurrence of DRX at grain boundary region in the coarse grained initial structure.
On the other hand, the evolved microstructure at higher strain rate was quite inhomogeneous, i.e., the mixture of equiaxed DRX fine grains and pancake-like initial grains.
Subsequently at the peak starin (ε = 0.4), obvious number of DRX nucleation appeared at grain boundaries and triple junctions.
The twins were formed during migration of the grain boundaries [2].

Moreover, there is no possibility of estimation of these data in a system with a higher number of components.
Here s is the grain boundary segregation factor and δ is the grain boundary width [39].
An estimate of the product s · δ of grain boundary segregation factor s and the grain boundary width δ is sketched.
Having measured both bulk and grain boundary self-diffusion rates one may use the Borisov semiempirical relation [74] and estimate the grain boundary energy, γgb, as γgb = RT 2a20NA ln (Dgb Dv ) (25) Here a0 is the lattice parameter and NA is the Avogadro's number.
Guiraldenq, Diffusion intergranulaire et energie des joints de grains [Grain boundary diffusion and energy], J.

Elongation increases remarkably with increasing the number of bainite laths within an ALPS.
Size of ALPS would correspond to grain size in steels without precipitation.
These microstructures does not precipitate on grain boundary.
It has been clarified that size of γ grain was around 400 μm.
It suggests that size of ALPS reflects so-called 'grain size'.

The fully recrystallized grain structure suggests that grain nucleation and growth have been completed during cooling of the extruded samples.
An increase in the number of grain nuclei during the fast extrusion can lead to an increased fraction of recrystallized microstructure in the case of MN11.
This post-yielding decrease in the AE activity can be explained by the increasing number of twin boundaries and/or of sessile dislocations which reduce the free length of moving dislocations, and the exhaustion of twin nucleation activity.
The stress required to initiate twinning could be expected to vary over the grains in a sample, the grains in which twinning was easiest would twin first.
A small number of large grains can determine the overall AE count rates

For very small particles, PV can actually be seen as the number of particles in the unit volume.
By using quantitative metallographic analysis, the graphite size is measured Level 7, where the average diameter of the graphite particles × 100 (mm) = 1.68 number of graphite nodules (pcs/ mm2) = 679.
Fig.5 Metallography showing the grain size of the measured carbon steel Quantitative Metallographic Analysis of Copper.
The analysis of non-metallic inclusions and grain size of carbon steel can quickly and easily provide with desired outcomes.
And the average grain size analysis of copper is also proven successful.

The grains are quite fine with 0.9%Wt alterative in the alloy.
Interdendritic material is solute atoms of Sn which is enrichment of solid solution (black areas) and with a certain number and size light-colored compounds.
Grain growth rate increased with the increase of temperature.
Figure 5 shows that with increase of alterative content, the grains size is more uniform.
Grains of Cu-20Ni-5Sn alloy grow up continuously with the increase of homogenized temperature.

Under situations where the number of oxygen vacancies and hydroxide defects is rather low (few defects relative to total number of oxygen sites), the concentration of hydroxide defects (in molar fraction) is given as: (7) where Acc| denotes a general acceptor.
Consequently, the grain Figure 14.
The ratio between La and W determines the number of oxygen vacancies in the materials.
The uptake of water increases with increasing number of available oxygen vacancies.
Magraso, Transport number measurements and fuel cell testing of undoped and Mo-substituted lanthanum tungstate, J.

The large cracks in real plants may be created by the initiation of grain-sized micro cracks, coalescence of cracks, and subcritical crack propagation over a long term.
Because grain-sized micro cracks can be initiated in grain boundaries almost perpendicular to the tensile direction, the possible number of cracks is given by Nmax=Simulated areaAverage grain size (2) Step 2: The initiation time for each crack is assigned by the random number based on the exponential distribution Eq.(1).
The crack length is given by the random number from normal distribution.
As a simulated area was 10mm´10mm and average grain area was 0.08mm´0.08mm, the possible number of cracks to be initiated was 15625.
Fig. 6 Number of cracks as a function of time.