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So, the analysis of texture evolution in route Bc is highly dependant on the number of passes.
In addition to the number of passes, developement of texture and its relationship with shear plane existing at intersection of inlet and exit channel of ECAE die are main factors influencing the grain refinement occuring during ECAE process [6].
After N = 4 (Fig.1(d)), fragmentation of elongated grains is more complete with the fraction of ultrafine grains increasing.
The weakening of texture for N = 3 and N = 4 are the conditions where fine scale dynamically recrystallised grains were seen as the number of passes increases.
Bulk texture studies using XRD indicates that after N = 1, the value of texture strength decreases with increase in number of passes and texture is very weak after N = 4.

The distribution of abrasive grains on the grinding tape is represented by number density, and the material existence probability that is represented by Abbott-Firestone curve is modified by considering machining parameters.
(ii) Cutting edges are distributed "uniformly at random" in the surface layer, and the number density of them is ρ.
(iii) Abrasion, fracture or falling-off of abrasive grains are negligible.
By substituting C1 for C0, C2 can be obtained, and Cn of an arbitrary number n can be calculated recursively.
The number of calculation cycle Nc was decided that Nc = 2fot where fo is the oscillation frequency and t is the process time.

However, the coercivity of the former is higher due to its smaller grain size.
From it, it seems that the structures of both samples are dense, and their grains are of uniformity with no abnormal grain growth.
Larger grains tend to consist of a greater number of domain walls.
As the number of walls increase with grain size, the contribution to magnetization or demagnetization due to wall movement vis-a-vis that due to domain rotation increases [5].
The number of ferrous ions on the octahedral B sites plays a dominant role in the mechanism of conduction and dielectric polarization.

In addition, the original fine grains and continuously refined grains can enhance the strength by restricting the growth of grains and motion of dislocations.
In addition, it shows that the grain size of samples is not very small (fine grain of ~20 μm and coarse grain of ~50μm).
It can be seen that the grain structure was inhomogeneous and mainly consists of relatively fine equiaxial grains of ~20 μm and coarse grains ~50 μm.
Fig. 3d, e and f (i.e. elongation of 15%, elongation of 24%, fracture, respectively), obviously, the grains were stretched, and the number of twins increases gradually.
At the same time, many fine equiaxed grains around coarse original grains.

The average grain size is 10μm and no abnormal large grain is seen.
When the strain level continue to increase, the number of small grain decrease and some large grain appear once again.
Abnormal grain growth [J].
Abnormal grain growth and grain boundary faceting in a model Ni-base superalloy [J].
Influence of the primary recrystallization texture on abnormal grain growth of goss grains in grain oriented electrical steel [J].

As the image intensity in the Z-contrast is approximately proportional to the square of the atomic number, STEM technique is especially well suited for understanding the role of heavy impurities in grain boundaries composed of much lighter ions.
Fig.1 shows a Z-contrast image of the Y-doped 31 grain boundary in Al2O3.
Z-contrast STEM image of Y-doped  31 [0001] tilt grain boundary in alumina.
According to the first principles calculations, the presence of Y at the 7-membered rings was found to increases the number of bonds, and the bond strength was increased due to the higher covalency of the Y-O bonds [3].
This should result in a much stronger grain boundary, which explains why the Y-doped grain boundaries can have such a large increase to creep resistance despite the fact that only a small amount of Y is present [4].

In the present model, both the number of potential nucleation sites per unit volume and the rate at which solute atoms from the matrix join the nucleus depend on the nucleation site and are either related to the lattice parameter (homogeneous nucleation), to the grain size (nucleation at grain boundaries) or to the dislocation density (strain induced nucleation) [5].
Grain Structure Model.
In [4] a nucleation rate RN is derived by the number of dislocations per critical nucleus that recover with time.
The grain orientation spread was used to discriminate between the original and the recrystallized grains [13].
Only in case of samples with negligible recrystallization during the compression, the crack propagates along the whole grain boundaries of the deformed grains, tearing apart the grains, often singling out individual grains (Fig. 2 right).

To produce a range of different structural states the initial coarse-grained samples were subjected to HTP with the following number of rotations of the mobile anvil n=0, 0.25, 0.5, 0.75, 1, 1.5, 3, 5, 7, 10.
Dependence of long-range order parameter (a), internal strains (b), size of the domains of coherent scattering (c) and microhardness (d) of Ni3Al on the number of mobile anvil rotations n.
As strain increases, three systems of shear bands form, their number increases but the width decreases.
Deformation of such materials is realised by a large number of small micro-shears along grain boundaries.
Thus, shear deformation by grain-boundary sliding and micro-shearing along grain boundaries becomes difficult.

However, the full benefits of using platinum can only be achieved if a number of simple basic precautions are observed in the daily practice.
The detrimental influence of different “platinum poisons” is summarized by a number of case histories resulting from inadequate caution in practice.
Other examples of “poisons” are phosphorus, boron, bismuth, silicon, sulphur and a number of heavy metals, e.g. lead, zinc, tin, antimony.
The presence of silicon is not surprising, as this will be found at high concentrations in a large number of samples, usually in the form of SiO2.
The carbon has diffused into the grain boundaries leading to grain boundary separation and porosity.

Meanwhile, the crystalline grain had a uniformity distribution, and the grain size was about 9.5~10 grade.
When the tempering temperature rose continuously to 680℃, a large number of supersaturated precipitation carbides happened along the grain boundaries, and began to gather and grow forming black network microstructure, as shown in Figure 3(c).
The number of club-shape precipitates increase at the beginning and reach peak number at the tempering temperature about 625℃ then decrease to a certain quantity at 680℃.
Figure 7 shows particle number of precipitation in different temperatures.
Consequently, the reduction in the number of M3C carbides leads to an improvement in the fracture toughness [6].