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The values of Vx =0.34 (<111> fiber) and Vx Journal Title and Volume Number (to be inserted by the publisher) 3 =0.171 (<100> fiber) are obtained (the relative error has been estimated and reaches ±0.04).
The first one is related to more or less spherical and stable grains with a relatively important grain size (30 µm in diameter) and are mainly connected to the two main orientations.
The intragranular misorientation for all this category of grains has been calculated and is more or less similar for all grains (not higher than 5°).
The advantage of nucleation and growth related to the <100> orientation is rapidly lost at the beginning of the process and gives the opportunity to a large number of orientations to nucleate and grow inside the deformed matrix.
During recrystallization, the <100> oriented grains develops first from the highly deformed areas at grain boundaries, in the intermediate regions of the wire.

The change of number, morphology and distribution of precipitation phase are the important facts to make the alloy strengthen.
It’s shown that tiny equiaxed dynamic recrystallization grains appear gradually along grain boundary after hot compression.
Compared to T5, the size of these large grains is little difference.
A large number of precipitated second-phase particles are produced after T6 heat treatment, as shown in Figure 2(b).
It shows that the number of the dimple is little and fracture morphology is mainly stonelike after T6 heat treatment, as shown in Figure 3(b).

The average grain size of 9~12 � is measured by specimen A, and the specimen B Journal Title and Volume Number (to be inserted by the publisher) shows 10~32 � in an average grain size.
The CuZnAl alloys have a tendency to grow large grain sizes.
By metallurgical methods, typical grain size is 0.5~2mm, and the grain size can be reduced to about 100� by grain refining addition [2].
The achieved grain size with SPS processes is found to be very fine.
Journal Title and Volume Number (to be inserted by the publisher) [3] N.

During the second aging at 200°C, the specimen ARB processed by 4 cycles always showed higher hardness than the specimen ARB processed by 8 cycles, though the increase in hardness was similar, independent of the number of ARB cycle.
However, the size of the fine grains was still less than 1mm.
It is considered that misorientation at grain boundaries was increased and grains were subdivided by severe plastic deformation.
Plate or rod-like precipitates having length of several tens nanometers were also observed on grain boundaries and within the grains.
In the specimen, the ultrafine grained microstructures fabricated by the ARB process kept fine grain sizes during the two-step aging

This leads to defragmentation (pinch-off) of grains, when grain thickness is in the order of the subgrain size.
Eivani explained the peripheral coarse grain structure of extruded 7xxx alloy as abnormal growth of statically recrystallized grains in the partially recrystallized grain assembly [10].
The potential nucleation sites on GB are therefore the number of subgrains in the deformed volume with high-angle grain boundaries [15]: (2) where d is the subgrain size, dG is the initial grain size, and SV is the surface area per unit volume [15].
These grains were characterized by EBSD.
The large grain size on the surface is indicative of gDRX occurrence where the number of nuclei is low (Eq. 5).

The observed effect was explained by the replacement of the pearlite constituents by lower bainite in the grain boundary regions which produced a local strengthening of grain boundaries.
The average grain diameter (area fraction occupied by the grains with certain diameter) is calculated also for each individual sample orientation.
The grain size data in this work were obtained using a grain tolerance angle of 5°and the minimum grain size was chosen to be 2 measuring points which were at least a distance of 1µm apart.
It is assumed here that a larger number of grains per area unit (i.e. a smaller grain size) will provide a higher density of high angle grain boundaries and therefore increases the resistance against crack propagation.
It can be explained by the replacement of the pearlite constituents by lower bainite in the grain boundary regions which produced a local strengthening of grain boundaries and the grain boundary regions.

Surface bump, cracks and other damage morphology accompanied by a large number of twinning organizations were found in the four-point bending test of magnesium alloy.
Prepare a number of lath-shaped samples of AZ31 magnesium alloy with the size of 160mm×6mm×12mm.
Under the tensile and compressive stress, a large number of bump appeared on the surface of magnesium alloy.
More coarse magnesium grains, more obvious bumping.
Also, smaller grain size is conducive to the twin deformation and grain boundary sliding which helps further coordination of twinning, while larger grain size is conducive to twinning, but not conducive to grain boundary sliding.

the grain boundaries of cermets, which strengthened the grain boundaries and improved the mechanical properties of Ti(C, N)-based cermets.
In addition, a great number of nanoparticles distributed at the grain boundaries, some of them without clear rim were observed.
With increasing nano TiC and TiN additions, the average grain size reduced, so the number of grains acting as crystal nucleus during sintering increased.
As a result, grains grew up in partial regions.
Furthermore, the nano particles distributing at the grain boundaries of cermets strengthened the grain boundaries (as shown in Fig. 2 b, grains 1 and 2), inhibited the crack propagation along the grain boundaries, and hence, improved the mechanical properties of the cermets.

Specifically, the Inconel 718 with refined grain size achieves 600% elongation [2,3].
The dominant microstructure and mechanical parameters of Inconel 718 alloy are Grain Size, Elongation Area, Grain Orientation and Texture Distribution, σ precipitations and secondary precipitations, Homogeneity and Stress influences [4,5].
In case of liquid cracking, Laves cluster around the liquation of grain boundary occurs liquid cracking.
Grain refinement of Inconel 718 alloy for dendrite space measurement.
McMahon, Grain boundary segregation of Boron in Inconel 718.

The average αp grain size is about 25 µm and the former β grains have a mean diameter of 60 µm.
The rotation angle ω around a given axis R defines the rotation which allows to pass from the reference frame of an αp grain to that of an αs grain.
The illustrative example presented in fig. 6a shows an isolated β grain and the adjacent αp grains (numbered from 1 to 7).
The αp neighbour which has the c-axis, the closest to a <110>β direction is number 5.
Similar results were observed for other isolated β grains.