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According to the TEM observations, the DRX microstructure can be categorized into three kinds: grains with low dislocation density, which are DRX nucleations; grains with low dislocation density around the grain boundary and high dislocation density in its interior which means that grains with dislocation density gradient and which are DRX grains in growth; grains with high dislocation density, which are fully work-hardened DRX grains.
The deformation bands are produced in the grain interior, and the small nucleation can be found around the deformed grain boundaries although they are few in number, which means the beginning of DRX.
With increasing deformation, the fine DRX grains increase and displace the coarse grains.
When the strain was 0.6(Fig.2 d), the DRX grains almost displaced the coarse grains fully.
The DRX microstructure can be categorized into three kinds: grains with low dislocation density, which are DRX nucleation; grains with low dislocation density around the grain boundary and high dislocation density in its interior which means that grains with dislocation density gradient and which are DRX grains in growth; grains with high dislocation density, which are fully work-hardened DRX grains.

With biaxial deformation, grain boundary slide occurred more frequently than with uniaxial deformation, causing grain boundary separation and formation of micro-voids between the grains.
In the vicinity of the cracks and at the locations of grain boundary separation, although deformation temperature at higher than the recrystallization temperature, fine grains (about 2 µm) showing in duplex grain structures were formed locally.
Otherwise, mechanism of fine-grained superplastic diffusion bonding mainly depends on grain boundary sliding and grain rotation by adjustment of void diffusion and dislocation motion, and going with obvious atom diffusion.
That results in the migration of different number of atoms in the twoides of interface.
Microhole is difficult to avoid, but its number and size is less than those of mechanical joining area.

The results of the XRD analysis showed that both the 5- and 10-coated layers are polycrystalline BaTiO3 with differences in terms of diffraction intensity, due to the number of layers.
The number of layers of 5 and 10 have thickness of 2.927nm and 4.456nm RMS.
Figure 3 (a) and (b) show the same layers but on a 3-D perspective where the layer grain growth is seen to produce rougher terrain due to the bigger and more uneven grains in the 10 layer film.
The higher 80,000x magnification, for the 5 layer film, shows grains and the grain boundaries, with some voids between the boundaries.
Surface of BaTiO3 for 10 layer coating CONCLUSION Multilayer BaTiO3 films have shown increasing grain size in proportion to numbers of layers, as verified via both AFM and SEM result.

With increasing both the distance from the center and the number of turns, the sum of the volume fractions of ε- and α’-martensites increases.
With increasing the number of turns to 10 the grain size in the disk center was refined to 95 nm, as revealed by dark-field TEM images (not shown here) [19].
It is noted that the hardness increased with increasing both the numbers of revolutions and the distance from the disk centre.
When the numbers of revolutions increased to 10 the hardness reached ~5150 and ~6130 MPa at the centre and periphery of the disk, respectively.
In this specimen the grain size was refined from ~42 μm to ~26 μm and large numbers of twin boundaries were formed inside the grains.

The material stability under shear (jamming) is ensured by odd circuits of grains in contact that prevent the grains from rolling on each other.
Grains are made of spheres of radius Ri with i being the label of the individual sphere with arbitrary choice of the numbering since there is no intrinsic long-range ordering.
We define then an adjacency matrix A of size n × n, where n is the number of vertices.
The blue circuits have even numbers of links and the particles can roll freely on each other.
Powder and Grains 2009, M.

It was shown the great scattering of triple product values, measured for different grain boundaries (GB) at the same samples.
Introduction Diffusion along grain boundary is one of the important processes, which occurred in polycrystalline materials.
Special attention in this paper is paid to the distribution of GBD triple product value for different grain boundaries.
On Fig.3a the numbers of GB triple product values at the temperature 400 °C for the groups are shown.
The alloy, containing 0.1 % Ce is characterized by much smaller grain size (less than 100 mm) than for pure Al and Al-Cu alloy (about 500-1000 mm) and thus the number of P values measured for the samples are 5 times larger.

The fine grain microstructure of DSS is capable of showing superplasticity at high temperature condition [6].
Microstructure of fine grain DSS carburized at 1223 K for 6 hours with initial pressure of 49 MPa Fig. 4.
Furthermore, the fine grain microstructure of DSS also enhanced the movement of carbon atoms deeper into the base material as it provides a larger number of grain boundary diffusion paths.
Initial hardness of the fine grain DSS before the SPC process is 426 HV.
Fig. 9 shows the relationship between carbon growth rate and temperature for the carburized fine grain DSS.

There were a lager number of dimples on the fracture surface,and the joints obviously present the characteristic of transgranular fracture.
When the beam current was increased to 17mA, the joints softened and the grain coarsened, so the joint strength decreased.
The fracture location of the joint is in the heat affected zone, the grains of heat-affected zone and the strengthening phase within the grains were became coarser affected by the welding thermal cycle.
A large plastic deformation occurs in the grains during ensile deformation process.
The weld undercut would occur with the electron beam current exceeded 16mA. 3） There were a lager number of dimples on the fracture surface,and the joints obviously present the characteristic of transgranular fracture.

The initial γ grain size was assumed to be 50-60 µm and a large number of Sigma3 twinning boundaries were observed inside the γ grains.
Equiaxed grains are observed that are much finer than the initial grains along the Sigma 3 twinning boundaries or γ grain boundaries.
Since the SFE in this alloy is very low, the stacking faults are assumed to form with extreme ease, with a result that the matrix grains are partitioned into numerous superfine grains.
In addition, ∑3 annealing twinning boundaries are considered to easily occur in CCMN alloy at high temperature especially after deformation because of the large increase in the number of stacking faults, since we observed large number of ∑3 annealing twinning boundaries even in the starting materials (Fig. 4).
The strain rate exerts a large effect on grain refinement when it is in the range 10 -2 to 30 s-1, and the grain size becomes extremely refined as the strain rate increases.

The purpose of the second treatment was a maximal enlargement of grains.
The sizes of the grains vary between 70 and 120m (Fig. 1, 2).
About 10000 more cycles are added to the total number of cycles providing fracture.
The increase in number of cycles leads to the formation of microcrack at grain boundary, and it propagates along grain boundaries (Fig.2), so that, along straight boundaries it propagates without apparent deviations.
The former austenite grain is etched (treatment N1).