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The grained structure in FG alloy as shown in Figure 1b, is presented by two different grain types, namely, coarse (average grain size 1.9 µm) and small (average grain size ~0.4 µm) grains.
Along with a-Ti phase grains, the type VT1-0 titanium alloy has a small number of b-Ti phase grains possessing a body-centered cubic (BCC) lattice and Im3m space group.
.% The implantation of aluminum ions in the type VT1-0 titanium alloy results in the formation of a number of phases possessing various crystal lattices.
Obviously, it is connected with the phase formation: UFG alloy has the largest number of secondary phases, while the FG alloy has the lowest one (see Table 1).
As is known from the work of Honeycomb [13], the dispersion hardening of the alloy depends on the number of particles, their size, distribution, and distance between them, and also the degree of atomic mismatching between the lattices of the precipitate and the matrix.

However, the mechanisms leading to grain refinement in pure Al and aluminium alloys under ECAE processing have only been the object of a limited number of studies [4-10].
This mechanism is based on the assumption that the original grains are deformed as the whole sample due to a limited number of active dislocation slip systems.
Journal Title and Volume Number (to be inserted by the publisher) 5 a b Fig. 2.
The fraction of these grains is low. 50 µµµµm d 100 µµµµm a 10 µµµµm b 50 µµµµm c Journal Title and Volume Number (to be inserted by the publisher) 7 Further strain up to ε∼12 leads to an increased fraction of recrystallized grains (Fig. 4d) outlined by HABs from all sides and an increased proportion of HABs (Fig. 3).
A negligible number of recrystallized grains could result from this type of CDRX.

A limiting grain size of the coatings has also been identified in the grain refinement process.
At high nitrogen pressures, poisoning of the magnetron targets and collision and scattering of the atoms and molecules become significant, and thus reduce the number and kinetic energy of the travelling species approaching the substrate.
A higher nucleation rate and a reduction of the self-shadowing effect of the deposition process will occur with an increasing number of depositing atoms/molecules.
Furthermore a limiting grain size in this grain refinement can be determined.
grain size), Ho = (minimum) hardness of the coating at large grain size, and PN = nitrogen deposition pressure.

The small grains have sharp grain boundaries and are almost free of dislocation.
Visible numbers corresponds to values of individual areas misorientation ef=120 Fig.5.
Visible numbers corresponds to values of individual areas misorientation X A a) B b) A X B Fig.7.
Numbers 1-4 in Fig.8a correspond to Kikuchy patterns 1-4 for grains/subgrains; c) orientation of analized area The high-angle boundaries (HABs) marked in the Fig.7 have bulges characteristic for the continuous dynamic recrystallization (CDRX) [7,8].
The effect of the introduced, additional loading is the increase in the number of the dislocation boundaries that cross mutually.

With increasing number of ARB cycles (N) the maximum punch force is increased, compare Fig. 3.
Hydraulic bulge testing: Burst pressure (full symbols) and von Mises equivalent strain (open symbols) vs. number of ARB cycles.
The grain structure merges to a bimodal structure consisting of equiaxed coarse grains and elongated fine grains.
For increasing number of ARB cycles the drawability decreases steadily like it is also observed in the bending tests.
All forming experiments equally show an increasing strength with increasing number of ARB cycles.

The study shows that the grain protrusion height obeys an approximate normal distribution, the static effective grain density is much lower than the theoretical density, and only a small number of diamond grains are effective in the grinding process with fine diamond grinding wheel.
The commonly used diamond grain recognition method based on low pass filtering and summits counting is clearly not adequate because the number of summits significantly obtained from the low pass filtered surface depend on the selection of the cutoff wavelength.
It shows that the grain protrusion height approximately obeys a normal distribution and the mean value of the grain protrusion heights is smaller than a half of the mean grain diameters. 0 500 1000 1500 2000 2500 3000 0 100 200 300 400 500 600 μ=1.434µm σ=1.378µm Number of grains /mm2 Wheel depth of cut d/ nm 0 500 1000 1500 2000 2500 3000 0 2000 4000 6000 8000 10000 12000 14000 16000 Static effect grain density /mm2 Wheel depth of cut d/ nm Fig. 6 Distribution of the grains protrusion height Fig.7 Distribution of the static grain density The static grain density is the number of exposed grains on the wheel surface per unit area.
Therefore, the static effective grain density is much lower than the theoretical density, and only a small number of diamond grains are effective in the grinding process with fine diamond grinding wheel.
The grain protrusion height obeys an approximate normal distribution, the static effective grain density is much lower than the theoretical density, and only a small number of diamond grains are effective in the grinding process with fine diamond grinding wheel.

Structure and Grain Boundaries of Ultrafine-Grained Nickel after Rolling and Forging at Cryogenic Temperature Evgeniy V.
For the grain (subgrain) size was taken to be the diameter of the circle whose area is equal to the grain (subgrain) area.
The authors of this work studied the effect of the number of passes during ECAP on the fraction of high-angle grain boundaries and the mechanical properties of this material.
Figure 2a shows the presence of a large number of extinction contours indicating high internal stresses in the material.
Small elongation of grains after rolling of UFG nickel in comparison with coarse-grained material [17] is due to the smaller grain size of ultrafine-grained material, which, in accordance with [1] is the reason for the smaller number of dislocations in the cluster in the shear plane and, as a consequence, less change in the shape of the grains.

Its microstructure (number and orientation of grains) can be determined by using Euler angles defining the orientation of each grain.
(a) (b) Fig. 6 Effect of the grain shape on the maximum stabilized stress at the global scale during TC load. 3.1.1 Interpretation of results In order to interpret these results, we inventory the number of activated slip systems by grain (ASSGs) during the cyclic stabilization phase for each value of (Table 3).
Note that ASSGs is calculated as the average of activated slip systems by grain, i.e., the total number of activated systems within the RVE in the stabilized state/ number of grains in the RVE.
These results can be explained by the amount of crystallographic slip, i.e., lg (=6)= < lg (=0.75)= despite the number of ASSGs (= 0.75) <number ASSGs (= 6).
These are thus the number of active systems that the amount of slip for each grain.

The numbers of small grains were seen dominating the microstructural pattern and no specific and uniform grain shapes were observed.
A similar number of pixels was used to ensure that a broad and wide image would be captured, using the same total mapped area of 30x35µm. 6438 grains was successfully mapped with a grain-size average of 0.2661µm, the smallest and largest grains being 0.0564µm and 3.2762µm, respectively.
The number of grains revealed was found to be twice many when compared with the number for CS50.
Due to the grains being heavily deformed, a large part of the mapped area could not be indexed, hence a large number of blanks were observed on the image.
Less force is required and a lesser number of grains has made a larger grain-size material prone to fail a lot more quickly than would a smaller grain-size material.

The accumulation of plastic deformation in the sample during multiple pressing can be assessed by εeff=1.16*n, where n is the number of GP cycles.
The average grain size is dav=12 µm.
The amount of large grains (d > 10 µm) is slightly more than that of average grains (2.5 µm < d < 10 µm).
Since the number of repeated pressing cycles increases, the relative number of grains with the size of d < 2.5 µm and 2.5 µm < d < 10 µm also increases.
The increase in the relative grain number (d > 2.5 µm) in comparison with that of ultrafine grains can confirm the dynamic recrystallization processes during higher pressing temperature (Fig. 3).