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In the FEG-SEM analysis, an interconnected porous structure with small grains was observed.
An increasing number of applications which demand for ceramics with advanced properties has been attracting attention in the last decades, specially in environments where high temperatures, extensive wear and corrosive reactants are present.
Mean grain size was determined by using the intercept method.
Furthermore, it was possible to verify the solid phase sintering, where the densification and grain growth are controlled by the diffusion across the grain boundary [27].
Different studies show that thermal conductivity is independent of the grain size [33, 34].

However, a major drawback of the process is the high cost of primary material due to the reduced number of suppliers and the employment of a complicated and sophisticated process for obtaining the primary alloy semi-solid material [ 1, 2, 3, 4, 5].
Heyn`s intercept method was also used to determine the grain size, with 25 grain counts made in each tested condition.
Table 4 show grain and globule sizes the alloys casting.
There is a direct relationship between grain and globule, because the larger grain size, the larger the globule size.
Hutt, The effect of grain refinement and silicon content on grain formation in hypoeutectic Al-Si alloys.

Coarsening of secondary phases increases the mean diameter of particles, decreases the number of particles per unit volume, while volume fraction remains constant.
This is accompanied by only a slight increase in the hardness of the weld metal and coarse grained HAZ.
Hardening factor is lower than in the coarse grained HAZ region.
The cause is the same as in the case of coarse grained HAZ region.
Weld metal hardening is caused by the same microstructure transformation as in the coarse grained HAZ region.

The amount of grain boundary increased enormously, and these grain boundaries held back crystals slipping, which strengthened the surfacing layer.
When being impacted, austenite organizaton created plastic deformation of grain boundaries.
Directional columnar grains turned to tiny grains and became dispersely distributing.
There were much dislocation among these grains, and the tangle and anchoring of dislocation increased in grain boundaries, which made the dislocation movement and glide of crystals very difficult.
There were large numbers of dislocations among austenite grains, and the tangle and anchoring of dislocation increased in grain boundaries, which made the dislocation movement and crystal flow very difficult.

Good coalescence of copper grains.
Number of supplementary vacancies can arrive at a value which corresponds to the density of vacancies in temperatures near the materials melting temperature.
Intense copper grains coalescence.
Good coalescence of copper grains.
Good coalescence of copper grains.

Four classes of flake copper powder with different grain diameters of 5 ~ 10 μm, 10 ~ 15 μm, 15 ~ 20 μm, 20 ~ 25 μm, respectively, are used for silver coating.
Fig. 2 shows that for copper powder with coarse grains, the silver content after coating is relatively high.
While the temperature is increasing, the activity of silver multiple ion increases and its contact with copper powder grains become more feasible [5].
In Fig 6b silver sediment is also granular and silver grains clearly increase in number.
The silver grains are, however, individual isolated grains rather than continuous and the copper powder base is clearly visible.

However, NiAl exhibits very low ductility below about 600K because of an insufficient number of easy independent slip systems in this range of temperature, which limits the range of potential applications as well as the possibilities of processing.
In the temperature region of 800K - 1000K there is a substantial amount of grain refinement leading to a steady state grain size in the order of 2 µm (800K) up to 10 µm (1000K) and a narrow grain size distribution, i.e., a homogeneous microstructure.
The development of the fraction of low angle grain boundaries (LAGB) with strain at a temperature of 1000K is shown in Fig. 5.
A steady state in terms of grain size and shear stress together with a considerable amount of grain refinement is established.
Above 1000K DDRX sets in characterized by a significantly higher mobility of grain boundaries.

And Fe can even refine the grains in the alloy.
This process is repeated using the same procedure but a fresh solution for each number of times until the whole sample has been dissolved completely.
The supersaturated Fe at high temperature would precipitate at a relatively low temperature, distributing along grain boundaries, as shown in Fig.4.
If there are enough Si coexisting, Al, Fe and Si phase would be formed and segregate on grain boundaries, as shown in Fig.5.
It shows that there are a great number of fine precipitates.

The micro crack length and number analysis was carried out on the microphotographs of the SEM results.
Figs. 1 (a) reveals that the grain size of EM Cast is 185µm, which is much finer than that of most common cast AZ31 alloy [4].
Figs. 1 (b) show the part-recrystallized grain structure with an average grain size of 25µm, and the some gross grains are as big as 350µm in size.
Figs. 1 (c) illustrate much finer grain structure of extruded profile, and the average grain size is 5.2µm.
These reveal that the damage level which represents with crack length and number is proportional to the apparent strain. i.e., at higher strain level the surface cracks' length is greater than that at lower strain level at both tensile and compression strain.

We compare three typical coarse-grained localization algorithms: APIT, Centroid and DV-HOP in simulated realistic settings.
Third, several representative coarse-grained algorithms are compared between simulated realistic settings and idealistic radio model.
Change of reference number.
The number of reference nodes increases from 20 to 100.
The number of nodes is 200 and the number of reference nodes is fixed to 48.