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The average grain size of this sample is 26nm.
Number density, chemistry and total solute distribution are also shown (f-h).
Turning to the solute dispersed in the intragranular regions, our analysis of cluster number density is provided in Figure. 3f.
The probability of the occurrence of random solute clusters was assessed and subtracted from the experimentally observed number density.
Combining the information on chemistry and number density, we find that 39% of the solute in the alloy is involved in atomic clustering and most of this is allocated to the modal clusters of size 8-12 atoms.

The difference in the number of adsorption centres, especially obvious for GBs in zinc, gives rise to a number of effects.
Experimental Grain boundaries of twin.
Grain boundaries of mechanical twin.
Fabricated twin grain boundaries.
According to [8] of special interest is the nature and number of adsorption sites at GB.

Formation of High-Angle Grain Boundaries in Iron upon Cold Deformation by Equal-Channel Angular Pressing S.
The basic ECA pressing parameters governing the processes of the structure formation include temperature, number of passes, pressure, angle between channels, and pressing route.
The grain size is 200-500 nm.
Distribution of misorientations for various routes and number of passes in ECA pressing at room temperature (EBSD analysis): a.
Route Bc, N=4. 10 20 30 40 50 60 0,0 0,1 0,2 0,3 0,4 Number Fraction Misorientation Angle [degrees] 10 20 30 40 50 60 0,0 0,1 0,2 0,3 0,4 0,5 0,6 Misorientation Angle [degrees] Number Fraction а b c d Summary The examination by the methods of transmission and scanning electron microscopy and EBSD analysis revealed the formation of partially submicrocrystalline structure with a grain size of 200500 nm in the α-Fe upon cold ECA pressing to ε ≅ 4.5.

It was revealed that UFG aluminum and magnesium alloys with a bimodal grain size distribution exhibit a number of anomalies in mechanical behavior.
Grain size distributions of aluminum and magnesium alloys after various numbers of passes of equal channel angular pressing (ECAP) is reported in [1-12, 15-17].
Grain size was 300 nm.
Mesocracks arise in the volume filled by fine grains and can intersect coarse grains.
UFG Al-Mg alloys have fine grain size of 1 μm and coarse grain size of 20 μm.

The initial workpieces were heated at 1150 °C for 5 minutes, resulting in a homogenous initial grain size of 200 µm which is assumed as the initial grain size for the first stage.
Different values of initial grain sizes are required to obtain the exponent of initial grain size, denoted as h in Eq. (1).
Measured grain sizes were averaged over a small measuring circle with diameter of 1000 µm.
Of course, employing the T-dependent Q and m increases the number of material constants to be determined through optimization and consumed time accordingly.
Optimized DRX constants including initial grain size exponent, strain exponent, strain rate exponent and dynamic recrystallization activation energy are acquired iteratively, minimizing the objective function of errors between target grain sizes and predicted grain sizes at the sampled points.

Due to the large number of participated abrasive grains, random shape, size and location, and higher grinding speed, it’s extremely difficult to study the formation mechanism and material removal mechanism of grinding surface.
Based on the relative motion trajectory of the abrasive grain and workpiece, the single abrasive grain grinding experiment can be divided to pendulum and swipe.
Single Abrasive Grain Grinding Experiment Single abrasive grain grinding experiment in the type of pendulum.
Adopting single abrasive grain grinding experiment, E.
Exchanging the position of abrasive grain and the workpiece, B.

Most β grains experience recrystallization, while for those β grains which are hard to be swallowed by recrystallized grains only experience recovery after β region heat treatment.
As a symbolization of grain growth, the large misorientation within grains exsits in some large sized β grains.
We can see the existence of competition relationship in large sized grains from the relatively straight grain boundaries (between blue, green and red grains).
At 1/2R layer after forging, the number of recrystallized grains in β phase decreases and most β grains with numerous sub-structures formed inside process recovery.
Conclusions (1) Recovery and grain growth occurred in β grains; while partial β grains recrystallized after α+β heat treatment.

The results showed that number of grains and seed-setting percentage of two L. chinensis ecotypes fluctuated within a certain range.
Variation coefficients of single spike grain number and seed-setting percentage were 79.37% and 87.2% higher.
The number of grains and seed-setting percentage of two L. chinensis ecotypes under saline-alkali soil habitat were lower than those under sandy soil habitat.
Results The number of grains and percentage of seed-setting.
From the average number of metrics (Table 1), the number of grains and seed setting percentage yellow- green ecotypes of L. chinensis were 1.124 to 1.302 times higher than grey-green ecotypes’ under the saline-alkali soil habitat, but number of grains is slightly lower than the gray-green L. chinensis ecotypes under the forest edge sandy soil habitat.

Classification of deformation methods of grain refinement in metallic materials The grain size in the most of as-cast industrial alloys is generally quite large (d>100 µm).
The formation of globular grains with high-angle grain boundaries occurs only in the regions of localized strain due to the preferential occurrence of metadynamic and static recrystallization.
All these factors result in the formation of a mix of high-angle and low-angle grain boundaries and regions of microstructure (colonies) with similar crystallographic orientations of α-grains.
The activation of grain boundary sliding results in an increase of the fraction of high-angle grain boundaries, spreading of crystallographic texture, formation of a very homogeneous equiaxed microstructure with the grain size d=10-15 µm (Figs. 2c and 3b).
The number of steps, temperature differences between them, iT∆ , and the total temperature drop between the first and last steps, ∆Т, number of strain passes on each step depend on the type of material and its initial microstructure.

Mechanisms of Deformation Behavior of Coarse-Grained and Ultrafine-Grained Ti Igor Alexandrova, Roza Chembarisovab Ufa State Aviation Technical University, 12 K.
A grain size is known to be one of the factors which define mechanical properties of metallic materials.
The coefficient of annihilation of the screw parts of dislocations , determined from the experience, according to [9] is equal to , (4) where is the share of the screw part of dislocation loops (), is the number of slip systems (for HCP metals ).
The grains contained a high dislocation density and other crystal lattice defects.
In connection with this the grain size has changed inconsiderably and made up 197 nm.