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While grain refinement is generally limited to a few microns by conventional thermomechanical processing, severe plastic deformation (SPD) processes have the ability to generate ultra fine grained (UFG) microstructures in most metals and alloys [1].
This generated a coarse-grained microstructure.
In contrast, the Al(Sc) layers contain a much lower number boundaries greater than 15°.
Hence, the recrystallized grains in the Al layers appear to migrate into the Al(Sc) layers.
(c) {111} pole figure of 84 recrystallized grain.

Such tension, in our opinion, is the basic driving force of synthesized grains monocrystallization process (Fig.2).
The faceted forms of grains do not exclude nanopores presence in their surface and volumetric layers.
Fig.2 Grains of multiligang garnet phosphor The technological process of grains monocrystallization from nanoprecursors created by us is opposite to nano-dispergation.
The microscopic analysis shows small concentration of growth defects (< 102 cm2) on the surface of grains.
A short-wave shift of Ce3+ spectrum is characteristic for a number of solid solutions Lu3Al5O12 -Y3Al5O12 where a shift of the spectral maximum occurs from λ = 530 up to λ = 500 nm and less (under a shift of the excitation spectrum to the short-wave side).

The average grain size is approximately 105 μm.
Within an equiaxed grain, only a few dislocation bands appear (Fig. 2b).
The recrystallized grains (with a misorientation larger than 15°) are much smaller than the as-cast grains and their average grain size is reduced to approximately 6 μm (Fig. 2c).
Moreover, a large number of subgrains and dislocation bands with a misorientation less than 15° were observed in the rolled samples, especially for the thin plates having a high deformation ratio (Fig. 2d).
Moreover, the as-rolled plates with high deformation ratios possess a great number of dislocations and grain/subgrain boundaries (Fig 2) which act as a highway for the diffusion of solute atoms in the matrix and accelerate the escape of Sc to the surface [16].

In the sintering process, NaCl played a role in the system by mainly providing a liquid phase sintering environment in order to promote grain growth and forsterite sintering.
The samples were then numbered according to the ratio of NaCl from low to high.
Fig. 1b also shows that forsterite grains get larger and small grains sinter together with the large ones, which grow better.
Therefore, grains have a certain degree of growth.
In other words, the thermal conductivity of the sample containing a large number of molten salts was lower.

BBTi ceramics contain more and larger plate-like grains than that in SBTi, the diameter of the grains in BBTi is about 8~10 µm, the thickness is about 2.5 µm.
It is found that BBTi ceramics contain more and larger plate-like grains than that in SBTi, the diameter of BBTi grain is about 8~10 µm, the thickness is about 2.5 µm.
Therefore, the grain size increases with the increase of Ba2+ doping contents.
When Ba2+ substitute completely for Sr2+ , the grain size will reach the largest.
BBTi ceramics contain more and larger plate-like grains than that in SBTi, the diameter of the grains in BBTi ceramics is about 8~10 µm, the thickness is about 2.5 µm.

It can be seen from Figure 3 that the cladding layer 1 has high surface roughness, low smoothness, and adhered to a large number of unmelted powder particles.
When reducing the scanning speed appropriate to 6mm/s, the cladding layer 2 is still adhered to a large number of unmelted powder particles, which indicating that low laser power cause absorb energy of powders is not enough to melt the powders fully.
It can be seen from Figure 4b, in the cladding surface prepared by the micro-nano composite powders is the fine equiaxed grains of about 10μm, and there are a large number of precipitates at the grain boundaries, and throufh EDS analysis, Cr contents were significantly higher than the substrate, which indicates that at the grain boundaries a large number of compounds by Cr and Fe, C, and other gathered.
(a) (b) Figure 4 The microcosmic appearance of cladding single-layer by the micro/nano powders The microstructure of cladding layer 6 prepared by micro powder is shown as Fig. 5, whose structure is also equiaxed grains but the grain size is larger than that of cladding layer 4, and the precipitates at the grain boundary is far less than that prepared by the micro/nano composite powders.
Analysts believe that the adding of the nano powders can prompt Cr activity to increase, which cause the increase of precipitates at grain boundary.

Introduction The number of methods of severe plastic deformation (SPD) are used now for fabrication of ultrafine grained (UFG) and nanostructured metallic materials, such as equal channel angular pressing, high pressure torsion, multiaxial deformation, twist extrusion, accumulative roll-bonding and others [1].
Ferritic grains were also checked out that volume fraction was of 35-37% and grain size - of 3-5µm.
The round shaped VC carbides of 75nm in size were observed both inside of grains and along grain boundaries (the volume fraction of carbides less then 5%).
The mean grain size in this martensitic state after HPT is 65 nm.
Electron diffraction analysis shows the presence of VC, V2C, V8C7 and V4C3 carbides inside grains and on junctions or grain boundaries with the size of 10-35 nm.

The magnetic properties of strontium ferrite fibers are mainly influenced by the grain size and fiber diameter.
For a single fiber as showed in Fig.3 a-c, the microfiber cross-section contains multi-nanoparticles and the particle number reduces with the increase in particle size.
From Table.1, it initially increases with the grain size, reaching a maximum value of 361.9 kA·m-1 (microfibers) and 523.6 kA·m-1 (nanofibers) at the grain size of 56 nm and then shows a reduction tendency with the grain size further increase.
Fig.4 Hc of SrFe12O19 micronfibers and nanofibers with different grain sizes Fig.4 shows Hc of the strontium nanofibers and micronfibers with different grain sizes.
From Fig.4, it initially increases with the grain size, reaching a maximum value of 523.6 kA·m-1 (nanofibers), 44.6% larger than Hc 361.9 kA·m-1 (micronfibers) at the grain size of 56 nm and then shows a reduction tendency with the grain size further increase.

Experiment Numbers Cr-bcc doping element Depositing time (min) ICr (A) structure Target current (A) 1 3 / / 120 2 3 W-bcc 0.3 120 3 3 Al-fcc 0.3 120 4 3 Al(Ce)-fcc 0.3 120 5 3 Zn-hcp 0.3 120 6 3 C- hexagonal 0.3 120 Methods.
The W doped Cr film exhibits dense columnar cross-section structure, however, the columnar grains were composed of Cr and W single layer of alternating and parallel arrangement periodically and the alternating layers can cross the grain boundaries between columnar grains into existence.
During the film depositing process the average grain size decreased significantly with the rare earth element Ce added.
Diffusion ability (degree) of Ce atom is inhibited by its own larger atomic radius, which is 0.270nm, and the number of crystal grains and interface between these grains increase significantly with the increasing of the nucleation rate of follow-up adopt Cr atoms, so the average grain size decreased significantly and the crystallization degree improved with the rare earth element Ce added into the film.
The Zn atoms can easily diffuse into the Cr crystal grains and form the replacement solid solution with Cr atoms.

The mean grain size was calculated by the scherrer’s equation.
The phase and grain size of YBCO power were investigated by XRD.
The grain size of the powder was not uniform.
Dispersion of YBCO powder According to related reports[15-17], the reasons for agglomeration phenomenon of powder were as follows: 1: after grain refining to the nanometer level, the surfaces of particles had a large number of positive and negative charges, as well as the shape of the particles highly irregular.
The grain was refined and achieved nanoscale.