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A number of techniques have been employed to synthesize this material in thin film and ceramic forms [2].
Grain size was obtained from SEM micrographs using direct measurement of grain length across the center of each grain.
This reduction in preferred grain orientation seems to be associated with the decrease in grain size.
Observed grain size reduction behavior can be explained by solute drag effect of La2O3 dopant on the grain boundaries of BIT ceramics which reduced diffusion rate and excessive grain growth.
Grain size was found to decrease with increasing La doping content which partly contributed to grain packing and orientation observed.

It was found that pattern quality improves with increasing atomic number with the FIB milling parameters needed to be adjusted accordingly.
The technique was used to investigate the recrystallization behaviour of a particle-containing nickel sample, which revealed a number of features of the recrystallizing grains that are not clearly evident in 2-D EBSD micrographs.
For aluminium, there are also a lower number of clearly identifiable bands compared with both Cu and Au.
The ion-milled surface reveals both silica particles and recrystallizing grains (arrowed).
The first micrograph does not clearly indicate that a particle is associated with this grain but further sectioning reveals a ~ 3 µm particle completely contained within the grain; this is strong evidence of PSN.

These grains are numbered 018, 023 and 045, and had the following initial orientations: 018 = 27°/ND rot.
The very wide spreads include some Cube and a much higher proportion of b fibre components. a) grain 018, b) grain 023 and c) grain 045.
a) b) c) Fig. 4 Texture component map of 3 grains (initially 20-30° rotated Cube) after e=1.2 rotated to Cube/b fibre orientations. a) grain 018, b) grain 023, c) grain 045.
(a) grain 45, (b) grain 129 and (c) grain 177.
The simulation part of this work has been achieved during the postdoctoral position of R.Q. at Cornell University, for which partial support has been provided by ONR, under grant number N00014-09-1-0447 and N00014-05-1-0506.

(3) The grain number of unit volume: =
(4) The grain number of unit area [2]:
(8) Numbers of dynamic grains on the grinding area per unit time:
This is because the average normal force per grain is less than the holding force for a single grain .With the conduct of the grinding, grains gradually become dull and grinding force increase.
Fig. 4(b) Thickness change under different grain volume ratios.

By using combustion synthesis under high gravity, TiC-TiB2 fine-grained composite ceramics with hypoeutectic, eutectic and hypereutectic microstructures were prepared through rapid solidification.
The FESEM and EDS results showed that TiC spherical grains constituted the matrix of the hypoeutectic ceramic composites, as shown in Fig. 2(a), while a few of TiB2 platelets were embedded in the TiC matrix, and there were also a few of white (Cr,W,Ti)3B2 phase were filled in between TiC spherical grains and TiB2 platelets.
By referring to TiC-TiB2 eutectic composition ceramics with 50mol% TiB2, the fine-grained TiB2 platelets with grain size less than 1 µm were embedded in the TiC matrix, as well as the uniform distribution of (Cr,W,Ti)3B2 phase could be observed in Fig. 2(b) .The TiC-TiB2 hypereutectic composition ceramic matrix with 60mol%TiB2, consisted of a number of TiB2 platelets grains and a few of irregular TiC grains distributed in between TiB2 platelets, whereas a few of coarse TiB2 platelets were observed in Fig. 2(c).
With the nucleation and growth of TiC solids, W atoms substitute a few Ti atoms, and a few of (Ti,W)C1-x solid solution with the crystal lattice similar to TiC were formed, subsequently, TiB2 nucleated adhering to TiC spherical grains and grew into platelets due to its AlB2-type structure of a P6/mmm space group, and were distributed in between TiC spherical grains.
Meanwhile, the highest bending strength of TiC-TiB2 eutectic composite benefited from the fined-grained microstructure, high fracture toughness and small-size flaw of the ceramics.

The measurement showed the region achieved a reasonable equiaxed grain structure with an average grain size of d » 60 nm.
The Al-Cu system demonstrated a consistent trend of microstructural evolution with the Al-Mg systems during HPT with increasing numbers of turns.
With increasing numbers of HPT turns for 20 and 40, a gradual expansion was observed in the severely mixed edge regions.
Significant grain refinement was achieved to demonstrate true nanostructure with an average grain size of d = 30 nm in an equiaxed microstructure.
Langdon, Twenty-five years of ultrafine-grained materials: Achieving exceptional properties through grain refinement, Acta Mater. 61 (2013) 7035-7059

In this study, the WL zones formed in fine grain to fine grain RR1000 welds are examined.
This image was taken by using a double diffraction spot generated from the inclined grain boundary (see the insert) where the grain A and grain B were overlapped.
The number density is very high in the WL zone.
The spherical morphology and the very high number density of the reprecipitated g¢ in the WL zone are shown in Figs. 7a.
The number density is very high.

This could be attributed to different corrosive resistance properties of NC nickel and coarse-grained nickel coatings.
Based on the above results and analysis, the different tribological behavior of NC nickel and coarse-grained nickel coatings can be understood in varying lubricated condition by considering the effect of the grain size, the number of grain boundaries and tribochemical reactions.
Wang et al. [4] have proved that the hardness increased with decreasing the grain size and the friction coefficient decreased with decreasing the grain size under dry friction conditions.
It can be explained as following: the passivation first started on surface crystalline lattice defects and NC nickel materials have high density of grain boundaries and dislocations inside grains when lubricated using ionic liquid.
Therefore, it is believed that the high fractions of coarse-grained nickel coatings will provide an increased number of active sites to quickly form a continuous and protective passive film.

Using electron and atomic force microscopy, it was shown that the size and shape of the grains of the films which were obtained by joint condensation of metal and fullerenes depend on the type of metal, the ratio of the number of metal atoms to the number of fullerene molecules, and the process conditions (substrate temperature, intensity of component delivery to the substrate).
Structure of Ti-C60 films with different component ratios: a - nTi /nC60 = 1; b - nTi /nC60= 6; c - nTi /nC60= 12 Fig. 2 shows the dependence of the average grain size of the Ti-C60 and Au-C60 systems on the ratio of the number of C60 molecules and the number of metal atoms.
Dependence of the average grain size in metal-fullerene materials on the ratio of the number of C60 molecules and the number of metal atoms (Ti, •Au) Surface Plasmon Resonance in Me-C60 Island Films The transmission spectra of metal-fullerite nanostructures with different surface densities of the metal and fullerene components were studied.
Grain boundaries are internal surfaces, therefore the ratios of diffusion flows into the grain and along the surface of the grain are described by the same equations as for the volume and surface of the crystal.
Grain-boundary diffusion in thin films.

Overall features are explained qualitatively by a model in which tensile stress makes the number of effective pinning sites which have appropriate activation energies for discontinuous motion of domain wall more, while annealing process makes just the number of pinning sites such as defects and grain boundaries less.
The magnetic Barkhausen noise measurements have been reported and discussed in relation to heat treatment, grain size, strain, and hardness [1,2].
The distortion makes the local crystal magnetically anisotropic and the easy axis of the magnetization is not continuous anymore near crystal defects or grain boundaries.
The number of effective pinning sites which have sufficient Fig.2.
The annealing process makes just the number of defects and grain boundaries less.