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In (a), it was shown that the coarse precipitates with size from several μm to several 10 μm were formed uniformly for the whole crystal grain on the specimen surface, in furnace cooling FC material to room temperature after the solution heat treatment at 493K.
In the case of FC material, it was thought that large number of Ge atoms were carried near surface and vacancy disappeared and the coarse Ge precipitate was formed with residue Ge atom because high concentration of vacancy existed at high temperature such as 623K during furnace cooling and the diffusion rate was large.
The cause of this phenomena is thought that large number of solute atoms accumulated near surface during quench hardening and then it was grown to μm sized precipitate during subsequent aging treatment because the bond energy of Ge atom with vacancy is considerably larger than that of Si atom10).
According to the results of TEM observation14), the Ge precipitate with average size of 124 nm was uniformly formed in crystal grain, however, the precipitate‐free zone was also formed near the grain boundary and the coarse Ge precipitate with average size of 254 nm was formed.
Therefore, it can be thought that the Ge precipitate on grain boundary became starting point of break and it made breaking elongation smaller.

Indeed, a number of research projects have been conducted with this objective in mind, aiming to promote the efficient use of various co-products and wastes.
Grain size distribution of studied materials (shale-slag mixtures) and standard range.
This improvement in bearing capacity can be attributed to the fact that slag grains are more resistant than shale grains from compression tests (Fig.4).
Slag grains exhibit very sharp asperities (angular shape) after crushing.
However, they diminish further with the addition of slag grains.

At the same time, the high pressure shock wave caused by laser propagate into the material which formed high density dislocation in the surface of the samples, and the γ' is divided leading to increase the sub-grain.
Because of the deep residual compressive stress, high density dislocation and much more sub-grains, the vibration fatigue strength is improved about 180MPa by LSP.
The step size should be constant and of sufficiently small size, and the number of tests sufficient, such that existing statistical guidelines to establish the mean fatigue limit strength can be used.
The grain is big and dendritic structure is obvious.

The local mechanical properties are mapped via hardness tests and the local microstructure is revealed by both of the ferrite number (FN) estimation and conventional metallographic examination.
The ferrite contents of the welds representing by ferrite number are shown in Figures 2(e) and 2(f).
The ferrite number is larger than 6 in the welding zone, and then sharply decreases to less than 1 across the fusion line to base metal (Fig. 2(e)).
In the welding zone, the ferrite number shows a variation ranging from FN 5 to 9, and a flatter distribution in GTA weld and an increasing to surface is shown in SMA weld (Figure 2(f)).
For the microhardness shown in Figure 2(a), there are a few factors affecting the hardness: (1) the residual ferrite content which can strengthen the dual phase microstructure, (2) the morphology of ferrite where lathy ferrite is harder than vermicular ferrite [3], (3) grain coarsening due to higher heat input, (4) grain refining at the boundaries of each welding pass [4], and (5) work hardening during cooling of weldments with restrain [5].

However, magnesium being a hexagonal close-packed metal has a limited ductility and poor formability at room temperature due to an insufficient number of operative slip and twinning systems.
Sometimes very large grains were observed due to abnormal grain growth, the original of which remains to be investigated.
The grain size in AZ31 remained comparably small, even during deformation at 400°C (Fig. 13).
The elongated (deformed) grains have a <1210 >, the small globular (recrystallized) grain have mostly a <10 10 > direction parallel to RD.
The deformed grains had mainly an orientation 1010< >||RD while the recrystallized grains overwhelmingly developed a <1210 >||RD texture component.

There are a number of interesting points that can be observed about the microstructures.
A limited number of observations have been performed to determine the dislocation behavior in these alloys.
The temperature dependence of the yield strength has been examined in a number of the alloys.
There are a number of interesting features.
<100> slip provides only three independent slip systems, which is insufficient for generalized plastic flow in a random polycrystal [18] and leads to strain incompatibilities at grain boundaries and, hence, fracture at low temperatures.

The crystallization was mainly composed by the surface crystallization and supplemented by the bulk crystallization when the grain diameter of the samples was less than 300µm [3].
The formation rate of crystal nucleus affects the curve peak height and the number of nuclei in the specimen.
So there was a linear relationship between (δT) P and the number of nuclei, which was in proportion to the number of nuclei in the specimen.
For the same weight samples, 36.0±0.1mg, the formation number of nuclei increased with the prolongation for nucleation as well as the crystallization peak.
For this reason, nucleated at 730℃ for 2h and treated by crystallization, the content of crystalline phase was suitable, grain were homogeneous and mechanical property was better.

Vanadium produces its effects by increasing strength and improving toughness, primarily through a combination of grain refinement and precipitation strengthening．Because vanadium is the most soluble one of the rnicroalloying elements, the vanadium containing steels tends to be relatively easy to cast continuously.
By using recrystallization controlled rolling, the grain size of hot rolled ferrite in vanadium microalloyed steels can be refined to 4μm．
Table 2 Liquidus temperature of Al2O3 -CaO- Na2CO3 slag Number Al2O3(%) CaO(%) Na2CO3 (%) Liquidus Temperature (℃) 1 68.4 31.6 7 1473 2 68.4 31.6 9 1468 3 68.4 31.6 11 1429 4 68.4 31.6 13 1456 Fig.1 Liquidus temperature of Al2O3－CaO－Na2CO3 slag with 11% Na2CO3 Phase Composition of Al2O3-CaO- Na2CO3 Slag.
When the temperatures of the Al2O3-CaO-Na2CO3 slag rises, the internal thermal motion of their ions become even faster, the number of chaotic ion become more and more, the number of free ion increases, and directional migration number of ion also increases.
It is knock-on certainty the electrical conductivity must increase with increasing the directional migration number of ion.

Titanium and its alloys have been known to possess good metallurgical stability and act as grain refiners for aluminum based alloys [3].
The electrochemical properties of the alloy are determined by microstructure, including distributed precipitates and distributed sub-micron dispersoids which are often located on the grain boundaries.
Therefore, subsequently the number of nuclei is increased and the growth of grains is restricted.
On the other hand, the enrichment of solute atoms leads to the formation of Al-Ce-Zn phases, which mainly distribute in the grain boundary area, thus the grain growth is further inhibited.

Due to the intrinsic capability of perovskite structure to host ions of different size, a large number of dopants can be accommodated in the BaTiO3 lattice [1].
The average grain size is decreased with the increasing content of Sb2O3.
And the uniformity of grain size is improved by Sb2O3 doping.
With increasing amount of Sb2O3 content, the secondary phase shows up as shown in Fig.1, and meanwhile, as shown in Fig.2, the grain size of (Ba0.732 Sr0.26Nd0.008) TiO3.004 ceramics reduces with the increase of Sb2O3 content.
It is found that Sb2O3 can control the grain growth and improve the uniformity of (Ba0.732Sr0.26Nd0.008)TiO3.004 ceramics.