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The higher vibration frequency is, the more the globular grains are and the finer the globular grains is.
The microstructure takes on fine globular grains for lower pouring temperature, whereas many clubbed grains appear when the pouring temperature is higher.
The results show that lower temperature is avail to the formation of fine globular grains.
The increase of the chilling rate can help to obtain more fine globular grains.
Acknowledgements This work is sponsored by the National Natural Science Foundation of China under the grant number of 50471065.

Spherical grains can be obtained by several semisolid processes in aluminium alloys.
As the dislocation density increases, there will be more grains for recrystallisation.
Thus, grain structure will be more refined [2].
Spherical grains of 7075 (a) treated at 575oC for 35 min (b) treated at 600oC for 20 min Fig 2 shows the SEM image of the spherical grains of 2024.
Comparison of the elongation at fracture results for 2024 and 7075 alloys Fatigue tests were applied after PH process to several numbers test bars in both quenching mediums (Quenching in RT Water / RTW-Q and Quenching in Boiling Water [80°C] / BW-Q after SHT).

The PTCR effect is considered to be a grain-boundary effect in the light of the models.
Results and discussion Influence of the dopant on the grain size Fig. 1 Dependence of grain sizes of the BST ceramics fired at 1300 ºC for 30 min in a reducing atmosphere on the dopant contents.
An obvious difference for the samples with doping 0.1-0.5mol% Sm3+ is observed in grain sizes.
The results imply that large numbers of the oxygen vacancies and free electrons are formatted in the samples.
The numbers of the oxidation of the grain boundaries for low donor-doped samples is much less than the specimens with doped high dopant content (0.25 mol%) during reoxidation annealing because of the grain refinement grains; moreover, a decrease in the resistivity jump ratios with increasing dopant content (above 0.25 mol%) is considered to be connected with the compact microstructure of the samples.

Meanwhile, the crystalline grain had a uniformity distribution, and the grain size was about 9.5~10 grade.
When the tempering temperature rose continuously to 640℃, a large number of supersaturated precipitation carbides happened along the grain boundaries, and began to gather and grow forming black network microstructure, as shown in Figure 4(c).
The most numerous of these precipitates were needle-shaped type, while a smaller number of precipitates were club-shaped type.
On the other hand, yield strength of HSLA steels has reached 780MPa [2], which were contributed to the large number of carbide precipitation distributed finely and uniformity.
Consequently, the reduction in the number of M3C carbides leads to an improvement in the fracture toughness [6].

The number of cycles to cause complete failure was taken as fatigue life ( fN ).
The alloy after solution heat treatment has an average equiaxed grain size of 110 mµ .
Small discrete carbide particles probably being of the MC types are found to be present in both the interior of the grains and at the grain and twin boundaries.
A TEM observation of the carbide particles in both the interior of grains and at the grain boundaries are typically shown in Fig.3.
TEM observations exhibited that at low strains ( %2.0grains, while at high strains ( %2.0>apε ) large number of slip bands with more than one slip system were seen within the grains.

Elongation rate also fell over the first peak may be due to: non-uniform deformation within the grain and the grain boundary strength increases due to reduced.
This is why grain boundaries off consecutive sub-band structure of the phenomenon.
In addition a large number at the bottom of thick GP conditions for the¢ hzone formation at high-energy distortion field for formation of increased energy.
（a）24h, intragranular （b）24h, Grain Boundary （c）52h, intragranular （d）52h, Grain Boundary （e）76h, intragranular （f）76h, Grain Boundary （g）90h, intragranular （h）90h, Grain Boundary Fig.3 TEM images of 7050 aluminum alloy under various age states 4.
Lead to a large number of grain boundary phase of ¢ h thicken and gradually began to gather over a non-coherent system of h lower energy relative to the direction towards the development of grain boundary off consecutive sub-band structure of the phenomenon

The gas and smoke absorbed during solidification of short circuited melted mark occurred in such environment will certainly have an effect on grain shape, grain size, holes distribution and impurity element distribution of organization of melted mark.
Introduction With the social development, home appliances are becoming electrified gradually, so the fire caused by electrical equipment is also increasing year by year, the number of which has been on the top of all kinds of fire.
During the 15 years from 1993 to 2007, there were 1,527,600 fire accidents totally in China, wherein, electrical fire accidents were 373,700, accounting for 24.5% of the total number of fire accidents [1,3].
The smoke particle on the surface of the wire during the process of short circuit melt and solidification influenced the nucleation, crystallization, holes formation, grain growth and so on of melting part.
Fig. 4 5g Fig.5 Conclusions The amount of smoke content and the viscosity of smoke in fire environment play a decisive role in the size and distribution of holes, grain shape, melt transition area and etc. of the internal organization of short circuited melted mark.

The film thickness was varied by depositing different number of layers.
Fig. 1: Average WO3 film thickness as a function of number of spin-coated layers.
As a result, the number of oxygen vacancies decreases[14] and transmittance are increased.
It was explained that the grain boundaries caused the light to spread.
This shift is associated to the compressive stress due to the lateral grain growth caused by neighbouring grains, after which outward growth normal to the deposition substrate occurs.

SEM study show that BaSiO3 doping can make grain grow uniformly and suppress the grain to grow up, and the structure of ceramics is compact with little pore.
This liquid phase can also purify the grain and grain boundary through adsorbing, promote uniform grain growing and restrain abnormal grain growing of (Ba,Sr)TiO3(BST) ceramics [4].
The formula of experiment Formula Number 1 2 3 4 BaSiO3 [mol%] 0 1 2 3 Results and discussion Effect of BaSiO3 doping on the dielectric constant and dielectric loss of BST ceramics.
The ΔC/C of BST ceramics Formula Number 1 2 3 4 ΔC/C[%](Positive temperature) 14.7 10.5 12.3 18.0 ΔC/C[%](Negative temperature) -19.9 -25.1 -24.2 -23.1 Effect of BaSiO3 doping on the material phase composition of BST ceramics.
From the Fig.6 a, b, c and d，it can be seen that there are many tiny particles on the grain surface and the grain size decreases with the increase of BaSiO3 content in BST ceramics, the tiny particles was finally disapeared.

The proper diamond mixture ratio is the prerequisite factor to Journal Title and Volume Number (to be inserted by the publisher) 155 marvelous property of the blade.
It is shown that for the harder and more wear-resistable granite (such as 657#), the percentages of harder grains and diamond grains with fine mesh number 50/60, 60/70 should be increased for the sake of greater resistance; Otherwise the percentage of 30/40, 40/50 should be increased and the toughness of diamond could decrease a little.
But if the concentration is too high and there are more diamond grains of fine mesh number 60/70, 50/60, the blade will become blunt although wearable, which will affect the cutting efficiency.
The size and shape of grain are different, and protrusion the height of diamond grain varies as well.
If the diamond density equals or exceeds that of No.g.5 and No.g.6, or the number of diamond grains is or goes beyond that of 60/70, saw blade will be blunt, cutting efficiency will be low, and hence the overall benefit reduces.