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In some alloys, refiners can act as nucleation sites for equiaxed grains provoking CET [2].
These curves show a sharp decrease in the number of detected fragments in the two experiments after the velocity jump.
(b)-(d) Cumulative number of moving fragments in microgravity and 1g horizontal solidification respectively (t = 0 s is defined as the time of the entry of the solidification front in the FOV) Measurements were carried out to determine the velocity of a great number of fragments for both experiments.
Spittle, Columnar to equiaxed grain transition in as solidified alloys, Int.
Bristow, Modelling of inoculation of metallic melts: application to grain refinement of aluminium by Al–Ti–B, Acta Mat., 48 (2000) 2823–2835

In surface patterning of silicon with pulse laser, pulse width and fluence were what would cause formation of ripples and grains.
For the same pulse width, the ripples were formed at lower fluence while the grains at higher fluence.
In addition, the mechanism of the ripple formation was different with different pulse width whereas the grain formation mechanism was independent of pulse widths [10].
Number of experiments to be carried out in each phase is determined using 3k full factorial design, where k is number of factors and 3 factor levels.
Thus, the experiment is designed with 2 factors, 1 block, and 3 center points which lead total number of runs to 11.

From the TEM analyses, MA’ed powder was found to have grain size about 10 nm (Fig. 1(c)).
The TEM micrograph shown in Fig. 2(d) indicated that the matrix grain size was about 170 nm, being still very fine considering the employed sintering temperature and time.
Mn substituted in Al sites seemed to suppress grain coarsening during sintering by diminishing lattice parameter mismatches, lowering diffusion and solubility of Al and Ti.
The TEM photo depicted in Fig. 6(a) shows several, submicrometer size Al2O3 grains.
The EDS spectra obtained by employing a focal size of 3 nm revealed that alumina grains were incorporated with (0.6~1.8%)Ti and (0.1~0.2%)Mn (Fig. 6(b)).

On the other hand, alkali metal-free glass substrate, which has recently been used as a large-size substrate for liquid crystal display, includes a lower number of alkali metal atoms or/and their molecules (totally less than 0.8 %) in the SiO2 matrix.
It might reflect the influence of O impurities out-diffused from the SiO2 matrix common to SiO2 and alkali metal-free glass, which are probably assumed to form shallow donor levels in α-GaN crystal grain.
Figure 7 shows the Arrehnius plot of the reciprocal numbers of near band-edge PL emission intensities of GaN grown on alkali metal-free glass as a function of 1000/T, that follows a thermal activation process described in literature [9].
The relatively strong near band-edge PL emissions are assigned as emissions associated with residual acceptor-like alkali metals and/or O donor impurities out-diffused from the substrates and with N vacancy generated under the Ga-rich condition in α-GaN crystal grains.
Growth 233, 22(2001). 0 0.2 0.4 0.6 0.8 1 1.2 1.4 0 20 40 60 80 100 120 1000/T (K-1 ) Fig. 7: Arrehenius plot of the reciprocal numbers of near band-edge emission intensities of PL spectra at 8.5 K from GaN layer grown on alkali metal-free glass substrate as a function of 1000/T.

Frequency factor Kfwas calculated by formulas: , , where stdFQj- the standard deviation of the j-th wavelet coefficients of AE signal, n - the number of discrete samplings of AE signal, m - the number of wavelet coefficients, xji - numerical value of the i-th discrete samplings of the j-th wavelet coefficient, - average number of the j-th wavelet coefficient.
The first peak on themicrofluidity stage AE can be associated with the collective movement of dislocation in the grain boundaries of the surface layers is preferably.
At this stage, a significant increase in dislocation density in a yield of dislocation clusters at grain boundaries and phase boundaries inclusions and the formation of a cellular dislocation structure with a dislocation density and the critical submicro cracks formation [13, 14].
This is due to a decrease in the deformed volume, increasing the dislocation density and significant grain refinement in the localized volume.
Last often results in the appearance of the grain boundary plasticity, having a low energy level of AE signals.

Introduction Ingots of titanium alloys are usually processed via a number of steps to breakdown the as-cast microstructure.
Initial hot working and annealing are performed in the beta field to produce a more uniform and finer beta-grain structure.
The size of the alpha and beta particles/grains depends on the precise deformation conditions.
After a height reduction of 50 pct., the number of high-angle boundaries in VT6 increased noticeably (Fig. 4b).
After a 70-pct. reduction, the microstructure of the alloys is partially refined to a grain size of approximately 0.5 µm.

Structural crystallographic defects, such as grain boundaries and dislocations, are believed to be among the main causes of these underperforming regions in mc-Si [1,2].
Their characteristic grain structure (long vertical grains that propagate in the direction of crystal growth) allows for a good comparison between treated and untreated samples.
While dislocation density is known to change from grain to grain, it remains fairly uniform within a certain grain along the growth direction.
Samples were cut perpendicular to the direction of grain growth giving two samples of similar grain structure and dislocation count.
Department of Energy, under contract number DE-FG36-09GO19001, and generous gifts from the family of Doug and Barbara Spreng and the Chesonis Foundation.

They reported that Sb addition caused a reduction in grain size and grain refinement of β-Mg17Al12 in the as-cast alloys.
The rod-shaped precipitates of α-Mg3Sb2 were precipitated and distributed at grain boundaries and within grains.
The number density and the area fraction of rod-shaped precipitates are obviously higher than those of the rectangle-shaped.
The grain size of precipitates in both alloys was measured by ImageTool software.
The grain size of them were about 1.5×50µm and 10×40µm

However, a limit number of study were conducted to study the corrosion behaviors of stainless steels that have been processed through cold work simulated by tensile test at various elongation and then expose to heat at different different time interval. 
The AISI 304 type tended to have more sensitization along the grain boundary of specimen with the longer exposure time to heat.
This could be explained by the twinning plane, as observed in Fig. 3., which created during the tensile deformation that initiated carbide in the grain [3] and then added up with the effect from carbide precipitation along the grain boundary by the heat during tempering process.
The tensile test caused the twinning plane which was the initiation of carbide in grain.
Subsequently, heat add up the effect of sensitization along the grain boundary.

At the second stage, the particles form stable periphery grain boundaries, the smaller grains are eliminated and connected to the large grains.
Large pores are formed at this stage and the densification changes with the grains enlargement and fusion.
Parameter and Property Value Diameter of the laser beam [µm] 450 Anisotropy factor, g 0.93 Laser power [W] 13 Scanning space [µm] 220 Speed of the laser [m/s] 3.5 Relative density 0.56,0.47,0.35 Average diameter of the grain [µm] 60 Attenuation coefficient of solid PA6 17000 Preheating temperature of the powder [K] 469 Initial melting temperature [K] 471 Finish melting temperature [K] 489 Thickness of each layer [µm] 100 Thickness of initial layer [µm] 1200 Number of the layers 10 always after the previous heating parts cold down to the preheating temperature.
This lead to less dense zones at the interfaces, and more dense others zones where the grains are completely melted.
Coarsening in sintering: grain shape distribution, grain size distribution, and grain growth kinetics in solid-pore systems[J].