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Number of investigations has been conducted to understand material flow behavior during FSW/FSP.
A number of approaches, such as tracer techniques using markers and welding of dissimilar alloys/metals have been tried to visualize material flow patterns in FSW [6-10].
This restricts grain growth.
Therefore the tool traverse feed rate must be moderate enough to limit grain growth, while at the same time providing the necessary heat to soften the material [3].
The upward movement can be seen from the flow of grains in TMAZ (grains are elongated in the upward direction).

Detonation spraying mode parameters are: detonation frequency 20 Hz, nozzle movement speed 1500 mm/min, and number of passes 4.
The Al2O3+5%Ti coating material has higher values of microhardness at grinding (by 10–15%) of the grain (grain size dG = 1.5–3.5 μm) and subgrain structures (subgrain size dS = 100–400 nm), the presence of particles of dispersed phases (size dP = 10–100 nm), and the density of dislocations up to ρ = (3–5)·109 cm–2 (Fig. 3a).
A grain and subgrain structure with a size of dG = 4–20 μm and dS = 200–400 nm, respectively, is formed.
It is proved that the method of multichamber detonation spraying (detonation frequency 20, nozzle movement speed 1500 mm/min, number of passes 4, distance from the nozzle of the multi-chamber device to the surface of the substrate 55–60 mm) allows forming coatings with a thickness of 230–450 μm.
The analysis of the experimental results of the study analytically established that a high level of coating hardening was achieved by ensuring the optimal structural and phase composition of the coating material: the formation of a fine-grained grain and subgrain structure, reinforcing nanoparticle phases, and a uniform level of dislocation density. 4.

Stainless steel substrates were grinded with sand paper number 600, 1,000, 2,000 and 4,000 in sequence.
Grain size of the films was calculated by using Scherr formular.
At N2 partial pressures of 20% have the largest grain size.
Therefore, the formation mechanism only depends on the ratio of the number Cr and N species from the different N2 partial pressure.
The increase of N2 partial pressure decrease the number of Cr species while increase more sufficient of the number of N species to form chemical reaction.

The crystallites’ number (Nhkl) indicates the number of different crystalline regions within a unit area.
This increase in surface roughness can be associated with the growth of grain sizes.
The formation of such grains related to the fabrication conditions of the samples.
It can be seen that the film is nearly homogeneous an the grains of Cu3SnS4 exhibit spherical shape.
Larger grains with fewer pores reduce the number of sites where charge carriers can be trapped and make it easier for holes to move through the material.

This texture places the grains in unfavorable orientations for the dominant basal dislocation slip mode in both tension and compression.
The hot working results in a grain size of roughly 10 µm.
The actual cycle number is also noted.
In contrast, (10.0) grains twin and de-twin reversibly throughout the duration of the experiment (251 cycles).
Acknowledgements Research sponsored by Los Alamos National Laboratory under grant number W-7405-ENG-36.

For titanium alloys, the α phase always preferentially precipitates at the β grain boundary.
According to Table 4, the αP phase grain size is slightly reduced between 960°C and 990°C.
As the temperature increases, the number and size of αP phases in the alloy gradually decreases, and the content of the β phase gradually increases.
The continuous grain boundary αGB causes the crack to expand along the grain boundary to reduce strength and ductility.
Because the content of primary αP phase is less, the number of dimples is less and the fracture surface is flat relatively, corresponding to the low ductility.

The FESEM result shows that the grain size of the TiO2 increases when annealed temperature increases.
The average grain size for the films is about less than 25.0 μm as the P25 powder was used.
However, it depends on the grain size.
When grain size becomes larger, electron movement from particles to other particles improves.
The grain size increased when the annealing temperature increased.

For this purpose, forty samples Peroba Rosa and eight samples of Jatobá were prepared for testing in compression parallel to the grain, following the recommendations of ABNT NBR 7190 standard.
Material and Methods Poisson’s ratios νLR e νLT for Peroba Rosa and Jatobá were obtained by considering results of compression tests on specimens (5×5×10cm) in the parallel direction to the grain, following the recommendations of the Brazilian standard ABNT NBR 7190: 1997 [6].
Compression parallel to grain tests were carried out within the Wood and Timber Structures Laboratory (LaMEM), Department of Structural Engineering (SET), São Carlos Engineering School (EESC), University of São Paulo (USP), with the aid of universal testing machine AMSLER, load capacity 25 tons.
Position of deflectometers in compression paralles to grain tests.
(3) From Equation 3, denotes the average value of the variable, t05 is the value of "t" test, Sx is the standard deviation and n the number of samples evaluated.

This result indicates this MnCO3 doped ZnPrCoO ceramic has a rather sluggish grain growth behavior compared with that of pure ZnO ceramics having a grain growth activation energy of ~60KJ/mol[15].
Interestingly, in addition to reveal the obvious enhancement of small concentration of MnCO3 on the nonlinearity of the ZnPrCoCrO based varistor ceramics, our current work also proves that Pr0.95Mn0.939O3 particles scattering within the ZnO grain boundary areas contributes mainly to the observed slow grain growth of MnCO3 doped ZnPrO based ceramics.
It is clear the addition of 0.5mol% MnCO3 has brought a slight decrease on the average grain size of the ceramics.
This secondary phase exists within the ceramics in form of small particles scattering within the ZnO grain boudary areas.
Acknowledgements The present study was partially supported by the Inner Mongolia innovation team fund, PR China, through the contract number of 83101004.

The presence of grain boundaries, microstructural discontinuities (as pores, low nitrogen soluble second phase) is computed using alternative equations.
Eq. 3 and 4 represents the diffusion near and inside of a grain boundary: ∂c ∂t = D ∂2c ∂x2 + ∂2c ∂y2         − V ∂c ∂x , x > δ 2 (3) for the neighbours nodes of the interface, where V is the velocity of grain boundary migration and δ is the grain boundary thickness and: ∂ccg ∂t = Dcg ∂2ccg ∂y2         + D δ ∂c ∂x         x=+δ/ 2 − D δ ∂c ∂x         x= −δ/2 , x < δ 2 (4) for inside diffusion of grain boundary, where Dcg is the diffusion coefficient for this region.
The space (x, y) is used in a grid M x N where M and N are total numbers of grid points in x and y, respectively.
But using indirect methods, such as electric resistivity of the sample to determine percentile of barriers, and working with this number on simulations it is possible a decrease in that uncertainty.
Efforts undertaken in order to produce more accurate simulation must take into account the grain boundary diffusion, as a tool to preview the nitriding through a sintered sample.