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It has been found that the grain sizes, Optical band gap and the preferred orientation growth of (002) plane were decreased with increasing of (Cu, Al) dopants amount in ZnO films.
The corresponding intensity and location of diffraction peak, full width half maximum, and the calculated grain size are shown in Table 1.
As the radiuses of both Cu2+ and Al3+ (0.0535) are smaller that that of Zn2+, during the replacement of Zn2+, pressure stress along c axle would be brought about to make the lattice constant d along c axle declined and grain size of ZnO film reduced.
It can be seen that with the increasing of doping ratio, the crystallization quality of films deteriorates, the average grain size decreases, and the thereupon the number of small granules in films increases; the scattering of electromagnetic waves while passing through films intensifies and thus the transmissivity declines.
The (Cu, Al) doped content affect the microstructure and reduce the grain size.

The results demonstrated that the grain boundaries emerged and there are some microcracks formed along grain boundaries due to superfast heating and cooling speed during the treatment process.
The electron-irradiation parameters include energy density of electron beam (15 J/cm2), accelerated voltage 18 kV, pulse duration 200 μs, pulse number of pulses 3.
After high energy density irradiation, the size of the grain is increased and the grain boundaries emerged on the surface without etching, which is related to the previous study [21,22].
The second phase and grain size in this direction existed change after 15 J/cm2 irradiation.
Conclusion After electron beam processing with high energy density, the grain size is increased and the grain boundaries emerged without etching.

Diamond wire saw wear includes coating wear and grain-abrasion, and the primary wear form is grits pulled-out.
This slicing method uses the slurry mixed abrasive grains as cutting fluid.
It can be found that numbers of diamond grits on the wire saw surface increase with the increasing of tack-on time.
When the tack-on time is 5min, the number of abrasives is lower because of the short time, so the wear resistance of wire saw is not high.
The wear of wire saw includes coating wear and grain-abrasion.

The structure of these alloys in the annealed condition is represented by α-phase and a large number of β-phase.
The number of β-phase at this area is 74%.
The number of β-phase in the weld metal amounts is up to 60.3%.
Metal HAZ β-up equiaxed grains.
"Effect of yttrium addition on grain growth of α, β and α+ β titanium alloys."

But whenever the stainless steels are heated at this range of temperature,major microstructural degradation occurs due to precipitation of compounds like chromium carbide (Cr23C6) at the grain boundaries and later inside the grains [3].
The Vickers hardness numbers (VHN) of the polished specimens were measured under a load of 100 gram.
Cr23C6 in the grain boundary and inside the grains.
It is observed that, in case of a plain SS 316 LN, the grains are mostly equiaxed, whereas after Mo/Nb addition, rectangular grains with prominent grain boundary are formed.
Ryu, “Effect of Grain Size on Cree Properties of Type 316LN Stainless Steel,” METALS AND MATERIALS International, Vol. 7, No. 2 (2001), pp. 107-114

The coating is composed of block phase, columnar grain, and dendrites.
Large numbers of elements spread between A and B region.
Fig. 4 shows the further amplified columnar grain area.
The average thickness of the evenly columnar grain was about 1.5-2 μm.
In this way, the columnar grain structure is gradually formed.

This can be done reducing the number and size of pores.
The grain size were determined with the mean intercept method.
In the etched section (6.b) the grain boundaries become visible.
The ZnO grains have a mean grain diameter of about 8 µm (Table 1).
Note the transition between the cavities of the pores (rounded grain structures) and the transcrystalline fracture of grains, which marks the boundaries of the defects (see arrows).

.% Zn after ball milling with an average grain size in the range of 33-12nm.
Refining grains could create a higher concentration of grain boundaries (GBs) which provide barriers to inter-grain dislocation motion, making the material harder to deform further, as suggested by the well-known Hall-Petch (H-P) relation [8-10].
Modeling results indicate that there is a transition from dislocation generation at sources within grains to grain-boundary mediated dislocation generation in the grain size range between about 100 to 10 nm.
The advantage of SPT over nanoindentation and micro tensile tests is the deformation zone where a large number of grains undergo deformation within the shear zone and overcomes the problem of stain gradient plasticity effects, grain size effects as well as the specimen size effects [13].
Therefore, the controlling deformation process can be mediated by dislocations inside the grain boundary or in a narrow "grain boundary affected zone" [31].

Introduction The MAX phases, numbering over 50, are ternary carbides and nitrides that have received considerable attention in the past decade [1-7].
Fine grained sample (FG Ti3SiC2) was made at 1400o C and coarse grained (CG Ti3SiC2) was made at 1600 o C.
Both Ti2AlC samples had the grain size of 100µm.
At same stress level, coarse grained sample has larger hysteretic loops than fine grained sample (Fig. 1).
At same stress level, coarse grained samples have larger loops and nonlinear deformation than corresponding fine grained samples.

A number of authors [3, 4] have generated finite element meshes directly based on actual microstructural images.
A difficulty that arises is the problem of touching or overlapping grains.
If two or more grains are touching, they will be seen as a single feature by the image analysis software.
The grain size distribution of both the real and the numerical microstructure follow a lognormal distribution with a greater number of small grains (see Figure 3b and 3e).
The real microstructure has a higher percentage of these small grains than its numerical counterpart due to small fragmented grains.