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Treatment of measured data, that is construction of texture pole figures (PF) and determination of their parameters, was carried out by the software, including a number of specially elaborated programs.
A grain size in the two-phase alloy depends on the ratio of volume fractions of both phases.
As grains become finer, the intragranular crystallographic slip proves to be more and more difficult due to the interaction of dislocations with grain boundaries and at increased temperatures the operation of the alternative deformation non-crystallographic mechanism inten-sifies.
Since preheating does not result in the complete α→β PT, new-arising grains of β-Zr are separated from each other by α-Zr streaks and therefore the sample deforms as a polycrystal, characterized by some mutual mismatching in behavior of neighboring grains.
In those cases, when under compression at PT temperatures contents of α- and β-phases in the sample are mutually comparable and their grains are sufficiently fine-dispersed, the intra-granular crystallographic slip proves to be restrained due to interaction of dislocations with grain boundaries.

The Cu substitution does not change the crystal structure, but it changes the grain size.
The increasing Cu concentration, it made the grain size larger, despite all the samples had the same treatment.
It has been confirmed from SEM images that the average grain size increases with increasing of Cu substitution.
That is one of reasons why the EDS data resulted in such numbers.
The volume and the grain size increase by increasing the Cu element.

Here W1 is the average grain size of the ceramic material.
b) After the tearing out of grain of ceramic material at the place of its location will be formed a crater, having the size and shape of the inverse-depth parts of the grain (Fig. 6).
The depth of the single crater is always less than half of the nominal size of the ceramic grain.
c) The number of torn grains of ceramic material and the number of craters on the treated surface depend on the homogeneity of the structure and granularity of tool ceramics.
Similarly, in an arbitrary order along the grain boundaries appear microcracks in the ceramic die.

Unlike the Cu films with columnar grain structures tested by Mönig et al. [5], the present Au film may have two or three grains through the film thickness.
With increasing the testing time to 450 seconds, the number of the voids gradually increased and the voids grew rapidly, as shown in Figs. 3(b).
The fact that a number of voids were formed in the present Au line is different from the findings by Mönig et al. [5] and Keller et al. [6], which showed that extensive wrinkles were formed inside the grains of the metal lines.
The voids observed here may be related to the promoted diffusion along grain boundaries (GBs) due to nanometer-sized grains in the films.
It was found that when the grain size and/or film thickness are decreased down to submicrometer scale, the inhibited dislocation motion inside grains would facilitate grain boundary-mediated plasticity and interface-induced damage, such as cracking along grain boundaries and twin boundaries, voiding at the grain boundaries as well as potential grain boundary sliding, etc. [9, 10].

When CoSO4 content of plating solution and the pulse frequency increase, the coating surface become smoother, microstructure become denser and coating grain refinement. when current density is small, coating crystalline grains size are tiny and the coating crystalline grains arrangement is relatively close.
Its grains is fuzzy and crystallite dimension is difference.
Comparing figure (a) with figure (b), coating grain arranges closely and the size is tiny when current density is small.
As frequency increases, the growth rate of crystalline grains is restrained, which results in the crystalline nuclei is small, nucleation number and the nucleation rate increases, microsurface sediment is compact and crystalline grains is tiny[8].
Meanwhile coating crystalline grains size are tiny and the coating crystalline grains arrangement is relatively when close current density is small.

Such grains (orientations) are dominant in the recrystallization texture. 1.
To examine the role of SE in grain growth, we selected first the orientations with the highest IQ, it means with the lowest SE.
Only 1% of total number of points having the highest IQ was chosen.
It should be underlined that the grayscale in Fig. 4 corresponds to a number of points with the lowest SE and not to SE itself.
Conf. on Recrystallization and Grain Growth (ReX & GG), p. 767, Aachen, Germany (2001) [2] J.

By evaluating the strains εϕψ for a sufficiently large number of angles (ϕ,ψ), it is possible to use equation (4) to find the unknown stresses σij through least squares fitting.
Postulate A2 (macrostress estimation from averaging across the diffracting grain ensemble) breaks down if the grain size becomes too large.
Then the number of grains contributing to the diffraction pattern becomes too small, the peak position accuracy and repeatability decrease, and interpretation of the results becomes unreliable.
Moreover, as sample tilting is performed, the measurements are collected not from the same grain ensemble, but from different grains.
A more accurate representation of the sample would be in terms of a combination of a large number of differently orientated grains.

Watanabe[10] observed the grain boundaries in the recrystallized Fe-3wt%Si alloy by SEM/ECP technique.
The axis X' is the projected direction of the axis XAB onto the grain boundary plane.
The axis Z is the normal direction of the grain boundary plane and the axis Y is the direction parallel to the intersection between grain boundary plane and (hkl)A and B.
First, a pair of the Euler angles was generated on the basis of the random number.
This is because a boundary can have the plural number of plane matching relation simultaneously.

From our point of view TE has a number of peculiarities in both stress-strain state and technological implementation which do this process attractive for both investigation and application.
We have previously described (see, for example, [1-9]) grain refinement under twist extrusion.
Numbers represent the number of TE passes Conclusions In the paper it was shown peculiarities of twist extrusion technique.
References [1] Beygelzimer Y., Orlov D. and Varyukhin V.: Ultrafine Grained Materials II; Ed.
Varyukhin: Ultrafine Grained Materials III; Ed. by Y.T.

Considering the large number of parameters associated with this material, the variability in mechanical properties is not surprising.
Figure 2 The microhardness of tungsten grains and matrix phase after deformation at various temperatures Microhardness indentations tests were run on alloys tested at different temperatures in order to find the contribution of W grains and matrix phase in deformation at various temperatures.
Figure 2 shows the hardness of tungsten grain and matrix phase at 10 gf load for a dwell of 10 sec.
From room temperature to 300 0C, there is failure in both tungsten grains and the matrix phase, but cleavage in the tungsten grains is dominant.
At these temperatures the tungsten grains exhibit ductile qualities.