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This Widmanstatten morphology (Fig. 1a), is formed from phase beta coarse grains (≈ 0.8 mm) obtained by heating over the beta-transus temperature followed by slow cooling (beta anneal).
When this temperature is reached, very coarse grains of martensite can be observed (Figs. 1g,h).
Vol. 220, Number 3/2006, (2006), pp. 241246

Figure 4(a) shows a grain of austenite.
The transformation strain causes a mosaic structure of crystal grains. [16] Thus, it can be estimated that before the martensitic transformation, the diffraction mode is dynamic and the intensity is lower.
In the case of such a low dispersion of X-ray wavelength, the number of crystals that satisfy Bragg’s law can be increased by crystal movement at the surface.

Three-electrode system was used to test the polarization Table 1 LY12 Aluminum alloy chemical composition (wt %) element Al Cu Mg Mn Fe≤ Si≤ content 91.4-93.7 3.8-4.9 1.2-1.8 0.3-0.9 0.5 0.5 Table 2 Experimental process condition and parameters Sample Numbers Current density (A/ dm2) Sample area (dm2) Test current (A) Eventually voltage (V) Concentration solution (g/L) PH Oxidation time (min) 1 4 0.138 0.55 510 15 11 25 2 8 0.138 1.10 510 15 11 25 3 12 0. 138 1.65 510 15 11 25 curve for four samples.
It can be seen that microarc oxidation ceramic film is formed by the combination of small grain which possess tiny hole in the centre and grow by the type of volcano awl[9].
In domain arc discharging, ceramic film is centered as tiny holes, though produced oxide continuously melt and rapidly solidification and combine with each others to thicken. with the increase of microarc oxidation time, the block grain formed later cover the earlier volcano and these link together with the type of cross-bridge, form a big ceramic connect skeleton.

A large number of combinations of different levels of these factors creates the problem of choice of optimal conditions of production of powders.
Osamu, Microstructural characteristics of large-scale ultrafine-grained copper.
Li, Ultrafine-grained copper prepared by spark plasma sintering process.

Also, it is important to keep in mind that homogeneity, commonly used with accuracy for bulk materials, becomes unreliable for modeling devices that have dimensions comparable to the material intrinsic lengths (grain size, microscopic fluctuations, interaction distances, etc.).
A fine grain silver halide holographic photo plate PFG-03C was used.
2 2 1 1 lim 2 sin 1 2 cos 1 lim 2 2 2 0 2 2 0 2 2 0 2 2 2 1 2 0 2 2 1 0 2 2 1 2 1               −=                      − =                     − = =               ⋅−⋅       − =                     − = =                     − =                     +            ≈ ∑ ∑ ∑∑ ∑ ∑∑ ∑ ∑ ∞+ = ∞+ = ∞+ = = ∞→ ∞+ = = ∞+ = ∞→ = = ∞→ σ λ π σ λ π σ λ π σ λ π ζ λ π ζ λ π ζ λ π ζ λ π k k k k k k k k k k m i k i m k k k m i k k i k m m i i m i i m k k k k m k k m m m I (1) Where I is the intensity of illumination; m is number of discrete sampling points; ζi is discrete

Just as the old saying goes：saving grain during the harvest year for the time we need it; when disaster occur, grain can be used as money for exchanging; this is called saving it when we have for the time we lack it[3].
[3] Jiatai Zhang,in:Han Dynasty architectural On a number of issues, edtied by Heritage (Third Series): Science Press, 2009 (12): 21(in chinese)

This attributes to changes in the material removal mechanism between the two grains.
The reason may be the decreasing load and the increasing abrasive grits numbers between the pad and workpiece.
These pits are considered as the gap between the grains.

Here, S and D stand for Single XY-scan and Double XY-scan, respectively, and the number following them indicates VED.
During rapid solidification, elemental segregation induced residual stress, which acted as the initiation point of cracks, and the cracks propagated along the segregated regions and grain boundaries.
Also, unlike other samples, D300 showed cracks aligned in the BD direction along high-angle grain boundaries (HAGBs), while the transverse cracks were suppressed.

Results and discussion 3.1 TiO2 single layer Fig.2 SEM images of TiO2 surface and AFM-RMS as a function of deposition condition for the PAEBE films (a,b) have more fine grain size and lower RMS values than those of e-beam films(c,d).
Although the deposition temperature of EBE method was higher than that of PAEBE, as a RF power increased from 0W to 200W, SEM images show that grain size of surface is significantly fine and RMS values decreased from 2.479nm to 0.95nm.
Schematic diagram of the PAEBE system Journal Title and Volume Number (to be inserted by the publisher) 3 accelerated into substrate by self-bias, and interacted with particles of the deposited layer or substrate.

a b Fig. 1: Backscattered electrons SEM images of the microstructure of a) tetragonal Ru45Nb55 with two levels of twinning b) monoclinic Ru50Nb50 with three levels of twinning As a consequence of a structural phase transformation with a decrease of the symmetry between the parent phase and the martensite, a finite number of variants is generated in each grain of the parent phase.
In the case of martensitic transformation, because of the unit cell deformation, the self accommodation of the variants is necessary for minimizing the deformation but the equiprobability of nucleation of the variants will lead to an equiprobability for the production of the self-accommodated group of martensite in each grain of the austenite.