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When examining the changes of the crystal grain of drawn wire by EBSD (Electron Back Scatter Diffraction Patterns), it wasconcluded out that grain size was compressed by conventional drawn wire due to share deformation and for alternate drawn wire it was confirmed that it was possible to inhibit the grain shrinking by 15% compared to the conventional drawing method.
ECAP method is used to get ultra-fine metal grain that has a higher workability.
Also, the further suppression of work hardening is possible with the increase of the number of times reversing the drawing direction.
Grain size observation of drawn wire by EBSD analysis 　In this analysis, to investigate the crystal grain size and crystal grain orientation of conventional and alternate drawn wires, Electron Back-Scatter Diffraction (EBSD) analysis was used.
In Fig. 10 the grain size of conventional and alternate drawn wire is shown.

The average grain size of 7075 aluminum alloy was refined to 12.81μm from 19.62μm at 300℃ for durations of 40min.
Because of grain refinement after annealing, the hardness of base metal increased significantly.
In B point, atomic number ratio between aluminum and magnesium was about 3:2.
In this case, diffusion layer width and grain size were relatively moderate and the joint strength was maximized.
But grain size grew up seriously, large numbers of intermetallic compounds formed.

Presence of coincident site lattices (CSL) on grains boundaries was investigated by repere diffraction method [1].
Intensity of grains orientations grows with ТFR Fig.5.
The following aspects: increase of grains number with cubic and octahedron orientations at controlled rolling; macrosymmetry (axis 4) of areas with higher pole density; as well as azimuthal distribution of zone pole density - testify dynamic recrystallization (DR) of steels in this area.
Significant number of special boundaries has been revealed here by repere diffraction method, which are characterized by presence of coincidence site lattice (CSL), for instance, tetragonal CSL (Fig. 9).
Grain maximums {111} accompanying them in this temperature range contribute to properties of low-alloy steel as well [4-5].

However, compared with a pure Cu film, salient grain growth of present dilute alloys does not takes place even at temperatures above 300 ºC , where the grain size is nearly the same as that of as-deposited films.
A large stress relaxation started to occur above 250ºC, associating with a large number of hillock formation.
Therefore, a large number of solute atoms most likely still remain in the Cu matrix, resulting in only a small decrease of resistivity at elevated temperatures.
It is clearly seen that on annealing at 400℃, the pure Cu film shows a large grain growth associating with a large number of void formation (dark spots in the photo), Fig. 4.
However, compared with a pure Cu film, grain growth of present dilute alloys does not significantly take place, showing nearly the same grain size as that of as-deposited films even above 300 ºC.

Grain size.
Figure 2 is the macro grain degree photos of the Nimonic 90 alloy by different remelting casting into test specimens, grain size characteristics are shown in Table 3.
As a consequence, the number of nucleation rate increased, average grain size tended to be smaller and smaller, which ranged from 127μm to 15.9μm.
a)1# b) 2# c) 3# d) 4# Fig. 2 Macro-photographies of samples for different remelting processes Table 3 Grain grade of the Nimonic90 Serial number 1# 2# 3# 4# Grain size(μm) 120~130 60~70 30~33 14~17 Grain grade 3 5 7 9 Microstructure.
Same researches pointed out the number of the γ ' in superalloy usually increases with Al+Ti, and the Ti / Al ratio has little effect relative to the number of γ ' [6].

F1=Fm+Fg+Fa+Fτ F2=Fd F1=F2 (3) The grain size depends on the number of nucleation.
The more nuclear number, the smaller sizes of grains.
The distribution of bubbles is affected by the number of nucleation and crystal growth[16].
Based on the relation, to build three kinds of models as follow: Model A: The large number of nucleation would decrease the average grain size, so that the distribution of nucleation around the bubbles is dense (Fig. 6(a)).
Model B: when the number of nucleation is low, the average grain size is big.

Most of sulfides within grains were Cr2MnS4, while sulfides at grain boundaries were mainly FeS.
The number of spherical sulfides is then increased.
Fig.2 The morphology of sulfides in grain.
As the cooling rate was increased, more sulfides were found in grain rather than at grain boundaries.
The number of spherical sulfides is increased and the sulfides show a catenular distribution at grain boundaries. 3) The sulfides are easily fracturing and the microcrack are formed in the sulfides when the steel is stressed by force.

In Fig. 2, the pure TiO2 film has a continuous and uniform sheet microstructure and is composed of TiO2 nano-grains with an average grain size about 20nm.
They are likely the congeries of the rutile of TiO2 crystalline grains.
Nevertheless, the surface is rough because of these bigger grains.
The photo-catalytic activity depends strongly on the concentration of doping ions and the film layer numbers.
But the layer numbers are important as well.

To meet low insertion loss requirement, a lower number of turns is required.
This fact was mainly attributed to that phosphorus ions with high electronic valence could increase cation vacancies in the grain boundary region, as a result, the speed of the grain boundary movement increased, thereby promoting grain size of the ferrites.
Due to the increased pores hindered grain boundary movements, enlarging trend of grain size became tardily as P2O5 addition exceeded 0.06wt%.
Hysteresis loss decreased with increasing grain size, which could be explained by the decrease of domain wall pinning factor, grain boundary, with increasing grain size [6].
Magnetic loss was also influenced by both grain size and porosity.

The result showed that it had excellent grain refining performance for commercially pure aluminum in 800˚C.
So far, AlTiB master alloy is still the most commonly used grain refiner in Al and Al alloys [3].
Research has shown that, AlTiC master alloy is considered as the most promising grain refiner of Al and Al alloy[6].
(a) 740˚C (b)800˚C (c)900˚C Figure 5 Refinement picture Figure 5 shows, AlTiC master alloy prepared at 800 ℃ has the best refinement, all of equiaxed grain, size can reach an aluminum (average grain size 0.026mm2) requirements; at 740 ℃, the temperature is low, refinement of AlTiC is bad, most of columnar crystals; at 900 ℃, the temperature is high, morphological of TiAl3 in the AlTiC master alloy changed, lowered refining effect, the center sites were equiaxed, columnar grain edges.
Reif, Development of Al-Ti-C grain refiners containing Tic.