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Microstructure analysis demonstrates that the grain sizes enlarge and the number of pores decreases with increasing Cu content.
The whole structure of Sr3YCo4O10.5+δ is loose stacked up by a number of irregular particles, and grain boundaries are not seen clearly as shown in Fig. 2a.
For Fig. 2b, the number of pores decreases, the grains enlarge, and one grain is usually connected with other grains.
Sr3YCo4-xCuxO10.5+δ (x=0, 0.2, 0.4) with higher Cu content, has larger grains and bulk density, less number of pores, which results in the pores in microstructure scattering the carriers weakly and hence increasing the electrical conductivity [18].
With increasing Cu content, the lattice parameters and unit cell volume increase gradually, grain sizes enlarge and the number of pores decreases, and the resistivity at room temperature reduces.

The recrystallized grains are defined by their grain boundaries.
These grain boundaries may separate the recrystallized grains from the deformed volumes or from other recrystallized grains.
(1) where (Sv)rr is the grain boundary area density separating recrystallized grains from other recrystallized grains, i.e. the recrystallized grain contact area resulting from impingement, and (Sv)rd is the grain boundary area density separating the recrystallized grains from the deformed matrix.
Thus, the contiguity ratio measures the fraction of the total grain boundary area of recrystallized grains shared by other recrystallized grains.
Recall that (Sv)rr = 2 nrr / Lt where nrr is the number of recrystallized grain /recrystallized grain boundary intersections measured in the test line length Lt.

The number of forging steps depended on the recrystallization kinetics.
The number of forging steps also depended on the phase composition.
This condition determined the number of forging steps at each temperature.
Dislocation Absorption Properties of Grain Boundaries A number of questions arise from the results presented above.
The achievement of submicrocrystalline structure in sheet rolling preforms enables the rolling of the Ti-22.9Al-22.7Nb-2.4(Zr,V,Si,C) alloy to be performed at relatively low temperatures which retains a high number of grain boundaries. 2.

A large number of elongated grains appeared.
At the same time, the presence of a large number of shear bands along several systems was observed inside the grains (Figure 3c).
The grains contain a large number of micropores less than 1 μm in size (Figure 6 c, d).
It can be assumed that the growth is hindered by a large number of non-metallic inclusions and micropores.
The material also contains a large number of pores ranging in size from 50 μm to 1-1.5 mm.

The addition of number of SiC particles to Al2O3 was able to significantly increase the hardness properties.
In this study, a number of composite manufacturing methods were compared from the results of properties by accumulative press bonding (APB), accumulative roll bonding (ARB), and repetitive press roll forming (RPRF).
Microstructure’s analysis behaviour used microscope optic was traced to determine the grain morphology and deployment precipitates on grain.
The movement of grain occurs due to the incorrect energy of high-alloying aluminium.
The movement of the grain to slip due to dislocation movement.

The grain size of primary α-Al grains was measured using ASTM E1382 linear intercept method.
The shape factor of primary α-Al grains and the secondary Al grains were also determined.
Number, size and distribution of pores were thus determined using the software package Volume Graphics Studio Max 3.3.
The number density is only 0.024 mm-3.
The number density is 159 mm-3.

It was also observed, during electrical measurements, that increasing the number deposited layers directly increased the overall capacitance of the thin-film structure.
The ZrO2 morphology showed grains from 6 to 10 nm of average size.
These large grains were associated to the perovskite phase only.
The 9 PZT sample showed large grains (bigger than 300 nm) and apparently were produced from collapsing and assemblage of small and medium grains.
Samples of 3 PZT, 6 PZT and 9 PZT showed small grains (~12 nm), large grains (100 - 300nm) and very large grains (> 300nm), respectively.

The microstructure after warm rolling shows elongated grains with high density of dislocation.
However, after electropulsing rolling, microstructure is much finer, shows some fine grains and sub-grains with lower density of dislocations.
After warm rolling, grains were elongated along the rolling direction, the grain boundary became blurry and the twins fragmented.
During electropulsing rolling, with the aid of electropulsing, the number of piling-up dislocations decreased and the number of mobile dislocations increased.
Therefore, the densities of dislocations reduced and some sub-grains were developed.

In DOE full factorial technique, number of test, N is according to formula which is N = yx, where y is represent number of conditions and x is act as number of factors [4].
The grain size on the test specimen was measured by using AFM.
From Fig. 1, grain size of Sample 7 shows bigger than Sample 3.
From the results, effect of temperature and gas flow is positive when the average grain size at high level is higher than average grain size at low level.
Meanwhile, the effects of vacuum and RF power have shown negative when average grain size at high level is lower than average grain size at low level.

In some cases, simple relationships could be established between L and the grain size, or other microstructural features.
This parameter, which we call the critical distance, can be used in a number of different ways to predict the local conditions of stress, or stress intensity, necessary for failure.
There is also a simple relationship between L and grain size in this case: fig.4 shows L values for one steel alloy, heat treated to give six different grain sizes [8] .
At the other extreme, concrete showed an L value of 10.5mm [11], similar to the size of grains (aggregate) in this material.
Predictions using the TCD (PM and LM). 0 50 100 150 200 250 300 0 50 100 150 200 250 Grain Size (µm) L (µm) Figure 4: Critical distance L as a function of grain size: analysis using the PM, taking experimental data from [8].