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Introduction Over the last two decades, equal channel angular pressing (ECAP) has emerged as a viable procedure for producing ultrafine-grained (UFG) and nanostructured metallic materials in a bulk form [1-4].
Exceptional grain refinement is achieved, resulting in unique structural and functional properties, including significant strengthening at ambient temperatures.
Taking this into consideration, our results in Fig. 2 suggest that route C has effected higher grain refinement than both routes A and BC.
Figure 3 (a)-(c) Plots showing the variation in mean hardness with number of passes for ECAP samples produced by routes A, BC and C; the mean hardness for the as-received base material is shown for comparison; (d) Comparison of hardness data for pass 4 samples produced by routes A, BC, C.
There is a general consensus in the literature that route BC leads most expeditiously to an array of reasonably equiaxed ultrafine grains whereas elongated grains are visible after four passes when processing through routes A and C, and also that route BC causes the most rapid development of high angle grain boundaries, leading to the conclusion that this route is the optimal processing route, particularly for pure aluminium [2,3].

The research result has indicated that the grain boundary in CuAu alloy could be expressed by fractal dimension [2].
The shapes of recrystallized grain boundaries in Ti alloy are self-similar and the fractal dimension of grain boundaries increases with increasing deformation degree and strain rate whereas decreases with increasing deformed temperature[3].
The grain size does not change too much, but amount of eutectic between the primary phases slightly increases, as shown in Fig.1b.
The ordinate is logarithm of the non-zero submatrix number, written as log (Nk), and the abscissa is logarithm of the submatrix side length, written as log (δk).
The smaller fractal dimension expresses that the morphology is simple and regular, and roundness of grain is better.

From Fig. 2, it is indicated that the small addition of BCZT could inhibit grain growth dramatically, in which the average grain size was reduced from 3.13 µm in pure PZT sample (Fig. 2(a)) to 2.87 µm in the 0.04 mol of BCZT added sample (Fig. 2(b)).
Those reasons might be the significant factor in restrain the movement of grain boundary during the sintering process [10].
It is suggested that the large number of polarization directions could enhanced the orientation of crystallographic after applying electric field and in turn, resulted in high polarization.
With an increase in the BCZT content, the average grain size was improved.
The maximum average grain size was observed at x = 0.08.

Metal forming processes have the advantage of producing near net shape parts, more product numbers and importantly high production rate.
Parasiz et. al. [4] studied the deformation size effect during microextrusion of micro-pins for CuZn30 by changing the grain size of the workpiece where material with larger grain size produced curved micro-pins.
As in the work carried out by Parasiz et. al. [4], the effect of grain size in our process was investigated as well.
Table 1: Grain size and hardness values after the two annealing conditions used.
GS: Grain size.

The solids in the bonded interlayer grew epitaxially from the mating base metal inward from the insert metal and the number of grain boundaries formed at the bonded interlayer corresponded with those of the base metal.
In the case of the specimen held for 72ks(Fig. 1 (c)), the liquid phase completely disappeared and the grain boundary formed at the bonded interlayer corresponds to those of the base metal.
From the above discussion, we can conclude that solids in the bonded interlayer grew epitaxially from the mating base metal inward from the liquid insert metal and new grains are not formed in the bonded interlayer.
Moreover, this finding confirms from that new grains are formed in the bonded interlayer of specimens held for 36ks and 72ks.
Fig. 6 shows the grain boundaries formed at the bonded interlayer.

Microstructure of deformed samples from the experimental alloy (Fig. 3) consists of elongated grains of α- solid solution and inclusions of intermetallic compounds arranged in the form of lines along the grain boundaries.
Metallographic studies have shown that the welded joint of the samples contains zones (Fig. 6), which differ in the shape and size of the grain.
In welded samples, a zone of thermal influence with a fine grain is determined, in which recrystallization processes have taken place, and the zone width is 1-2 μm.
The grain size was evaluated on oxidized samples, it was established that the grain size in the thermal effect zone is approximately the same and is 13-15 μm, and the grain size of the coarse columnar crystals in the near-weld zone does not exceed 2.4 μm.
Langdon, Influence of grain size on the flow properties of an Al-Mg-Sc alloy over seven orders of magnitude of strain rate, Materials Science & Engineering.

Scanning Electron Microscope images elucidated the influence of Zn on surface morphology and the grain growth for CdTe thin films.
ImageJ software was used to analyze the grain size and morphology of the annealed films.
Fig-3(a-e) shows the influence of Zn on morphology and also the grain growth at different annealing temperature.
Average grain size of the films for different annealing temperature was varied from 15-22µm.
Scanning Electron Microscope images revealed the effect of Zn on grain growth and surface roughness as well.

Information on local anisotropy field and the grain size was obtained from investigation of approach to saturation magnetization law.
In electroless plating, the composite particle shape and size of grain depend on phosphorus content.
An increase in the phosphorus content causes a reduction of the grain size [8].
Information on local magnetic anisotropy field and the grain size in the systems of exchange coupled grains can be obtained from investigation of approach to saturation magnetization (AMS) law [10-12].
We confirm that amorphous Co-P alloys of the same composition but in different morphologies occur in a number of distinct states, characterized by different degrees of nonequilibrium, which is manifested by different magnetic properties.

The corresponding number of oxygen vacancies also increas, thus the carrier concentration increas, resulting in lower film resistivity.
As indicated in Fig.6, when the temperature of heat treatment is 500,there are no obvious crystalline grain,but plenty of microcracks.
However, as the temperature of heat treatment is 600, Crystalline effect is very well, the distribution of crystalline grains is uniform and particlesize tends to be consistent.
On the one hand, higher tempreture can cause defective unmber in crystal boundary decrease and the potential barrier between grain boundary decreases.
In the experimental conditions, while the number of coating film is 8, the apparent performances and photoelectric properties of the thin films are optimal.

The cause of phenomenon is that residual stress born in aluminium alloy with the elongation, crushing and fibrosis of grain.
Thus, a great deal of abrasive dust is filled in SiC grains on abrasive paper so that the cutting part of SiC grain is decreased.
The processes affecting the wear rates of every ceramic coating, from big to small, are number 4, 1, 3 and 2 process.
At initial wear stage, the wear rate of ceramic coating treated by number 4 process drop down from 1.9 mg/min to 0.24 mg/min.
(Grant Number 09-007-05_013).