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The size of the SiC crystals is not uniform indicating local differences in growth rates, or in the induction time for the onset of abnormal grain growth.
Fig.1 shows that the number of small polycrystalline SiC grains is reduced with growth time and/or increasing temperature.
Thus, only a few SiC crystals grew to large sizes in a dynamic process which features abnormal grain growth from a distribution of fine grains by the mechanisms of solution/precipitation, or of SiC particle coalescence [13], as in Fig.1 (d).
The microstructure of all samples revealed that the fine SiC grains become sparse in the areas around the large SiC crystals, Fig. 1(b), 1(d) and 2(b-d).
While the MI CoSi/SiC system has the lowest density of such SiC grains, they grow at the highest growth rate.

The Kolmogorov-Avrami-Ishibashi (KAI) model is also known as infinite-grain model (IGM) has been successfully applied to analyze the switching transients in various single crystals.
Figure 3 shows the normalized remanent polarization as a function of number of reversal cycles.
The theory assumes that the rate of nucleation is constant throughout the switching process and based upon infinite grain model [2].
Equation number (vii) was used to fit the experimental data.
FIG. 2 Shows the versus E (blue color) and its Gaussian fit (red color) curve of the NKN sample. 0 1x105 2x105 3x105 0.2 0.4 0.6 0.8 1.0 1.2 Normalized Pr Number of Reversal Cycles FIG.3 shows the normalized remanent polarization as a function of number of reversal cycles.

Most of them were appeared on the grain-boundary.
They were found on the grain boundary and in the ferrite matrix, most of their diameter is about 60nm, even some diameter is under 30nm.The morphology and energy dispersion spectroscopy (EDS) microanalysis of those precipitates were shown in Fig.4.
The precipitates under different rolling parameters were also studied, the type and morphology of precipitates were not affected by rolling parameters, but the number and size of precipitates were changed.
When rolled at 800�, the number of precipitates was increased, the size of precipitates was bigger than those rolled at 700�, the reason is assumed to the Ostwald ripening during cooling of the hot strip.
In P-added high strength IF steel, after combining with N, the Ti atom will combine with Fe and P to form FeTiP because their higher stability, most of Ti was consumed and very small was left to combine with C, S, so the number of TiC and TiS, Ti4C2S2 was very small contrasted with the P lean steel.

They, compared to conventionally coarse-grained Ni-Cr alloys, exhibit dramatically increased resistance to liquid corrosion in a 3.5% NaCl solution, and to hot corrosion under molten salt of Na2SO4-Na2SO4-NaCl at 700 o C.
Hence, they exhibit excellent corrosion resistance, as compared to conventionally coarse-grained (CG) alloys [4, 5, 8, 9].
Moreover, the nanocomposites contain numerous grain boundaries (GBs); this causes highly enhanced diffusion kinetics of atoms in them with respect to in the CG alloy counterparts.
The mean grain size of Ni deposits was below 100 nm and its actual value somewhat relied on the size and content of the codeposited particles.
The outer layer (~50µm-thick) precipitated nanosized CrN, which increased in size but decreased in number with increasing nitridation depth (following BöhmKahlweit's mode); the inner layer (~5µm thick) exhibited larger-coarsened nitride precipitates (100- 200nm) which almost linked together [10].

With the increase of inflation, the number of bubbles increased, the contact opportunities between bubbles and mineral particles increased, and the recovery increased.
The grain size of diasporite in bauxite is relatively small.
It was crushed to grains with average diameter less than 3 mm using a single toggle jaw crusher.
With the increase of air inflow, the number of bubble flowing into the flotation cells per unit time increases, the total surface area of bubble increases, the contact opportunities between bubbles and mineral particles increases, the capture probability for mineral particles increases, and the recovery rate of Al2O3 increases.
With the increase of air inflow, the bubble number and corresponding total surface area of bubble increased.

The average grain size is 150µm [9].
Within the grains, the matrix structure is supersaturated with alloying elements.
A composition gradient also exists, and for most elements the concentration is lowest at the centre of the grain and increases towards the edge of the grain.
Overheating of a 6063 alloy has been shown to result in coarse grains, melting along the grain boundaries and potentially fracture of the billet [22].
The high temperature heat treatment has a number of benefits for the further processing and development of mechanical properties of the alloy.

The process employed low Zeta electric potential controlled growth to achieve big grain diameter 130nm.
In this work, the best conditions of grain diameter growth were optimized, which included pH, reaction temperature, digestion time, and so on.
Decentralized system of silicasol with more than 30 of absolute Zeta potential value was stable, while with less than 30 of the absolute Zeta potential value colloidal dispersion system was not stable, and the bigger of absolute number we obtained, the more stability the colloidal system will be.
From Figure 6, the appearance of silicasol is sphericity grain with size about 120-150nm. 3.2.

The position of each diamond grain relative to its mean position can be described by the following equation (1) As illustrated in Fig. 3, it will take a diamond grain Δt/2 to move from y=(A-δ) to y=A.
According to the model of material removal, the volume W of workpiece material removed for one grain is obtained as (10) where CL is the length of the lateral crack; Ch is the depth of the lateral crack; L is the distance over which the grain is contact with the workpiece.
From equation (15), we can see that the cutting force is affected by spindle speed, feedrate, diamond particle number and vibration amplitude in the rotary ultrasonic drilling hard and brittle materials with a constant feedrate.
And the influences of spindle speed and feedrate on the cutting force is stronger than the diamond particle number and vibration amplitude.
The diamond core drills (Hollow Drills, SAUER, Germany) with outer and inner diameters of 10 mm and 8 mm respectively, consist of metal-bonded diamond grains of mesh size from 120 μm to 140 μm.

The friction-stir processing (FSP), a variation of FSW, is applied to modify the material microstructure by localized grain size refinements and homogenization of precipitate particles [2].
For example, Ma et al. reported superplasticity in Al alloys subjected to grain size refinements via FSP [3].
Moreover, a number of studies focused on the understanding of the influence of texture on the mechanical behavior of the FSW Mg alloy to address its poor workability at room temperature due to the limited number of slip systems available in the hexagonal close-packed (hcp) structure [12,13].
The discrepancy between xxaε and xxcε could be related to the plastically anisotropic properties between a- and c-axis at grains of the hcp Mg alloy, which may cause the intergranular strains arisen from strain mismatch between grains of different orientations [13].
Considering the a-axis of grains can comprise the majority of grains in the strongly textured Mg alloy, the xxε along the a-axis can represent the mechanical behavior of the bulk than the c-axis [20].

Very fine grains of the size 10~30nm are obviously observed in the dark field image.
X-ray, diffraction analysis has given the mean grain size as 25nm.
Although the existence of disclination structure is confirmed within some grains, it is sure that ultra grain refinement to such a nano-size level results in marked hardening to around Hv=1OGPa.
In spite of increasing number of structural investigations, the nature and operation of deformation mechanisms in these structures is still matters of dispute.
This study is supported by Japan Society for Promotion of Science (JSPS) grant number: S-04107.