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During growth successive grain size enlargement takes place and leading to coarse grains in the range of several millimeters (Fig. 2).
Thus the grains do not seem to have any texture.
Grains with inclination angles less than 30 degrees prevail during growth because they laterally overgrow heavily off-oriented grains.
The reduced density of planar defects under optimized growth conditions could be since the number of carbon inclusions is strongly reduced and otherwise would cause defective growth.
This is the reason why grain 5 (Fig. 3, Table 1) led to a higher growth rate than grain 3 despite both grains are of 6H polytype with almost the same off-orientation but different inclination directions, <11-20> and <1-100> for grain 5 and grain 3, respectively.

At surface, where the crystallization of the grains is the most intensive, amount of the grains can reach about 77%.
The main advantage of the TRC technique is preferential grains growth [3].
The grains orientation was studied at surface as well as a cross-section of the strips.
During casting the high cooling rate forces the directional grain growth, which increases the number of preferentially oriented grains.
Thus, the lower amount of the preferentially oriented grains may be expected.

The grains in the C2 condition were finest.
The Al concentration in the grain boundary precipitate was five times as high as in the grains.
Zn was not detected in the grains while there was a great amount of Zn in the grain boundary precipitate.
Thus, we found that a number of solute atoms were segregated into the grain boundary.
In C1 condition the secondary phase of about 5 wm size was distributed in grain as well as grain boundary, while in C2 condition the phase of 10 wm was limited just to the grain boundary.

Grain size in brass scatters from 10 to 200 µm.
The increase of number of various facets roughly correlates with decreasing grain size.
Lead separates the brass grains one from another.
In case of twin GBs each 3 rd lattice site of a grain 1 coincides with a lattice site of a grain 2, and Σ = 3.
It can be seen that the numbers are rather similar.

The quality of ductile iron increases with the number of the graphite spheroids.
The quality of ductile iron increases with the number of the graphite spheroids.
This model treats a given number of polycrystalline grains having different lattice orientations.
The calculations are based on the modelling of the processes which occur inside and between grains.
As the result, the internal stresses for grains of different orientations and for the whole sample are predicted.

Mechanical behavior and microstructure evolution during superplastic deformation of the fine-grained AlCoCrCuFeNi high entropy alloy.
Microstructure of these alloys was initially thought to consist preferably from disordered solid solutions, which are stabilized by high entropy of mixing of the principle alloying elements due to their large number [2].
However, it was later revealed that increase of number of principle elements does not result in increased probability of solid solutions formation [3] and, indeed, many HEAs are composed from ordered or intermetallic phases.
For example, in recent work [6-8] the equiatomic AlCoCuCrFeNi alloy was hot multi-axial forged to produce a fine-grained structure.
The grains or particles of the Al-Ni-rich, Co-Cr-Fe-rich and σ phases have nearly equiaxed shape.

Deformation of Al by the multi-axial compression leads to grain refinement to ultra-fine grains (UFGs) and improvement in strength properties.
The sample in Fig. 4a shows the fragments of original grains and a few fine grains.
This sample had the highest homogeneous grain structure, as well as highest fraction of high angle grain boundaries (Fig.4d).
Most of the grain interiors were free of dislocation.
The number of grains with high-angle boundaries increased with increasing strain.

The peak intensity was also increased after adding the dopant due to the increasing of the number of oriented crystallite.
This observation was made by Law et al. which were found that the increase of the peak intensities on XRD pattern showed the number of domains oriented also higher [4].
The grain size is decreased with addition of dopants in PZT system.
Kalem et al. [7] also reported the reduction in the grain size has been attributed to the solid solution impurity drag mechanism in which the La concentration gradient present at grain boundaries was claimed to cause blocking of grain mobility leading to slower grain growth rate.
The addition of dopants remarkably decreased the grain size of the PZT sample because this effect influences the grain growth which may depends on the suitable device application.

SEM micrograph unveiled that the Jc was induced significantly by continuity of grain formation via grain size.
Generally micro cracks induced by a large number of low angles grain boundaries (GBs) through in melt-textured samples favored to restrict Jc in bulk materials due to parasitic nucleation via fluctuations of thermodynamic parameters during crystallization process.
Larger grain size manifest the lessen of grain boundaries [2,7].
Larger grain size will enhance the grains continuity, lessen the porosity thus enhance the Jc value.
Significant Orthorhombic tendency and larger grain size revealed by Y123 system decreased the number of grain boundries thus increasing grains connectivity and continuity as verified by SEM.

It was the intention of this work to investigate a number of open questions, which have been raised in state-of-the-art literature [2-6].
This analysis showed that within the RD-fibre grains the strain heterogeneities were mainly concentrated in the vicinity of the grain boundaries whereas the grain interiors were much more homogeneous (cf.
In the ND-fibre grains, on the other hand, the fragmentation was more distributed over the entire volume of the grain.
This produced a structure in which a limited number of excessively large grains gradually consumed the fine grains of the starting microstructure.
This mechanism involves the disappearance of low angle grain boundaries, which appear to be of key importance for the onset of local grain coalescence between grains that are only separated by low angle grain boundaries, cf.