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When such an aggregate is annealed, the recrystallized grains also possess a preferred orientation, which in many cases is even stronger than the deformation texture [2].
In the case of grain growth, the texture is determined by the grains, which, as a result of favourable orientation relationships, grow rapidly at the expense of the deformed matrix.
Generally, scanning a single area is usually not enough to cover a Title of Publication (to be inserted by the publisher) 273 sufficient number of grains to obtain a representative ODF comparable to that obtained by X-ray diffraction.
Engler et al [3] compared two quantitative measures to derive the minimum number of single orientations required to adequately represent the texture of a given sample and so to assess the statistical significance of the microtexture data.
In the present work, as all the ODFs had a medium intensity, at least 1000 grains were used per ODF analysis.

The size of equiaxed grains was 100mm.
A few new recrystallized grains with high angle grain boundaries were generated by boundary bulging and migration.
Fig.4 shows the EBSD grain boundary map and grain boundary misorientation distribution of the as-casted sample in Fig.3a.
It can be seen that there are a great number of low angle boundaries randomly distributed in the unrecrystallized grains.
Fig. 7a shows the ductile fracture morphology with a large number of dimples in the uniaxial simple tensile fractured sample.

Homogeneous films with an average grain size down to 60 nm were observed after heat treatment at 900 ℃.
Therefore, lead-free ferroelectric materials have been receiving considerable attention owing to the environmental issues of the present day to replace some lead-based components in a number of electronic devices.
A number of lead-free piezoelectric materials have been developed [1-4].
The images of KNN100-9 thin films which was heat-treated at 900 oC shows clearly grain boundary which average grain size approximates 60 nm, Figure 3(b) show the cross-section images of KNN100-9, the film was crack-free, smooth, and had a uniform thickness of approximately 300 nm respectively with surface SEM (c).
Conclusion Homogeneous thin films with an average grain size of 60 nm were prepared by heat treatment at 900 oC.

Metallographic observation showed that the microstructure of T2 copper changed from equiaxed grains to twins and the interaction between the dislocation slip zone grain boundary and twins promoted the super plasticity distortion in T2 copper.
Table 1 Yield stress of different strain rates Number Strain rate Yield stress[MPa] 1 0.001 329 2 0.01 333 3 1949 324 4 3305 353 5 4340 357 During the dynamic impact process, the effects of adiabatic temperature rise in T2 copper are notable.
The flow stress of metal is linked to temperature, strain rate and its microstructures, which contain dislocation density, grain boundary, grain size and impurities.
The microstructure of T2 copper changed from equiaxed grains to twins at the strain rate of 4347s-1.
The interaction between the dislocation slip zone grain boundary and twins promotes the super plasticity distortion of T2 copper.

So, RE is priority segregation at the grain boundaries, reduces the interfacial tension and energy, and decreases the driving force of grain growth, and hinders the movement of grain boundaries and inhibits the growth of grain.
First, RE can make the grain refinement, the grain boundary increasing and increase the resistance of dislocation movement.
It plays the role of refining grain fine grains by adding the appropriate amount of RE to duplex stainless steel.
Then a number of interstitial atoms that pin dislocations are reduced, thus the toughness of steel are improved [7].
Finally, the appropriate amount of RE that dissolved in the steel is often enriched in the grain boundary by diffusion mechanism, which reduces the inclusions segregating in the grain boundary, so it reinforces the grain boundary.

As the powers of the agitator increasesed from 0 KW to 20 KW, the refined grain size could be easily detected.
Some of the columnar crystals reach the length of 44 mm .When power is 10KW, chilling layer and the center of the casting parts are existed with a large number of isometric crystals .The columnar crystals become small and measuring the average length of it is about 30 mm.
The grain morphology has changed and group has been gotten bigger refining.
Without electromagnetic field, there exist thick and irregular shape grains in the organization.
Some sizes of the grains are more than 100 microns.

After remelting, YSZ also have no phase transformation, but the grain of the preferential growth orientation changed.
The substrate grain size is within 10 to 30 μm after spraying, and it is the same as the original substrate, grain size basically remains stable.
But grain size significantly grown larger after remelting, distribution in the range of 20 to 50 μm.
From the above analysis, oxygen diffusion channels increase by the change of substrate grain size after remelting.
After oxidation for 100 h, the number of diffraction peak of m phase increased, diffraction peak above 70° of t' phase almost disappeared.

Although the concentrations of Pb and Cd in grains were lower than other organs, Pb and Cd concentrations of grains under higher heavy-metal treatments exceeded the national guidance limit for three varieties of maize, suggesting heavy metal pollution may pose risks to human health.
The total number of subplots in the experiment was 15 (i.e. 5 heavy metal treatments × 3 varieties of maize).
In addition, the Pb concentration of the roots was higher than other parts, and the grain was the lowest (Table 3).
In higher Cd treatment, the concentrations of Cd decreased in the order tassels > roots > leaves > stalks > grains in variety A, whereas the order was roots > tassels > stalks > leaves > grains in variety B, and roots > tassels > leaves > stalks > grains in variety C (Table 3).
In lower Cd treatment, the concentrations of Cd decreased in the order roots > stalks > tassels > leaves > grains in all three varieties (Table 3).

Grain size distribution.
In Fig. 6, white bars exhibit the number fractions of all the grains, while black bars exhibit those of the grains within 15° from (0001) orientation.
The grain size decreases after deformation, and about half of grains smaller than 20μm has (0001) orientation.
All the grains greater than 70μm are (0001) grains.
Moreover, mean grain size of (0001) is larger than other grains.

Figure 1: Solar cell efficiency distribution of a mc-Si ingot (wafer number increases from bottom to top).
Yet if one has to deal with very large areas (a standard mc-Si wafer is 156mm x 156 mm) and large number of samples the traditional technique is clearly inadequate.
In the image of the etched wafer, on the other hand, grain structure is less visible.
Long and thin structures like general grain boundaries possess large elongation factor.
We developed an etching recipe, and an image capture and processing algorithm to deal with large sample sizes and numbers.