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After adding modifying elements B, Ti in ZA303：the microstructure of the alloy is from gross dendrites to uniform equiaxed grains , the quantity, morphology and distribution of the (α + η) have greatly change: the quantity of (α + η) is less, from a continuous network to intermittent block, and its end become blunt, or even cylindrical horn and dispersed distribution; on the grain boundary, the size of ε phase become smaller and dispersed distribution, the number of mesh ε phase reduced but intermittent strips increased; adding B, Ti have a good effect of restraining Al element segregation，so the foundry defects decreased obviously.
For this reason, modifying elements B, Ti can prompt the grains fine[1-3] (Fig. 2 a)).
For this reason: the microstructure of ZA303 is from gross dendrites to uniform equiaxed grains, the a) 11sample modification b) 12sample without modification Fig. 3 Tensile fracture surfaces of ZA303 quantity of (α + η) eutectoid is effectively reduced and the homogenization of the dendriticcrystal of aluminium-rich phase.The increase of dimples due to the equiaxial grain, play an important role in tensile strength and elongation increase(Fig. 3 a) ).
Modifying elements B, Ti in ZA303 can prompt the grains fine, the homogenization of the dendriticcrystal of aluminium-rich phase and the increase of tensile strength and elongation. 2.

Wetting of nanoparticles by liquid aluminium presents a number of challenges.
A number of techniques have been used to incorporate nanoparticles into molten aluminium.
Grain refining was accomplished using 5TiB master alloy to achieve a level of 40 ppm B in the melt.
Most particles and particle clusters remained at the grain boundaries.
Conventional grain refining improved tensile, yield and elongation values.

Nano grains in the boundary phase were observed, which might enhance the space charge behavior.
The ceramic body is thus a capacitor composed of a large number of individual minor capacitors that are in series with or parallel to one another.
Amorphous phase is observed at the grain boundary region between two semiconductive SiC grains.
The width of the grain boundary is about 200 nm.
The width of the grain boundary is ~200 nm.

Most of the available publications are devoted to ECAP, in particular to the dependence of the material properties on the number of the ECAP passes applied [15,16,17].
The average grain size was deq=300nm (Fig.2b).
The HE+ECAP combination gave a structure with the average grain size deq=327nm (Fig.2d) which was highly homogeneous with well-shaped equiaxed grains.
After subjecting it to HE, its structure became appreciably refined and contained well-shaped equiaxial grains and a small number of defects The average grain size was 200nm (Fig.3b).
The average grain size was 190nm (Fig.3c).

SEM micrograph showed the Jc is induced significantly by continuity of grain formation via grain size.
The doping of alkaline-earth metal does not just increase the number of holes in the CuO2 planes, but reduces the current blocking effect of grain boundaries [2,3].
Larger grain size will enhance the grains continuity, lessen the porosity thus enhance the Jc value.
Bigger grain size, minimum porosity and less of grain boundries is also founded with Y123 system.
The existence of impurities (Ca) and the continuous formation of the grain decrease the number of grain boundaries.

It can be seen that the microstructure under different solution temperatures are of equiaxed grain structure, and that the grain sizes increases with increasing solution temperatures.
The grain boundary mobility increases with increasing temperatures, which resulted in the increasing grain sizes with increasing solution temperatures for this metal matrix composites.
It can be seen that the microstructure under different solution temperatures are of equiaxed grain of different sizes, and that the grain sizes increases with increasing solution temperatures.
The formation of refined grain sizes should be due to higher energy storage caused by more severe deformation, which is benefit for the forming of more nucleus and more refined recrystallized grains.
Acknowledgement It is a project supported by natural science foundation of shanxi province China (project number: 2011011021-1).

Grain element and grain boundary Fig. 2.
As shown in Fig. 3, the average grain size increases with the extension of simulation time, while the number of grain declines.
Large grains grow bigger by swallowing small grains.
That is to say, the diameter of grain is gradually increasing with the extension of holding time, and the number of grain is gradually decreasing.
There is no difference of simulation results with different orientations when the orientation number is bigger than 50, so that Q=50, choice of material properties refers to Table 1.

Microstructures of the deposits and walls consist of columnar grains and equiaxed grains.
Microstructures of these deposits consist of two types of grains: columnar grains and equiaxed grains.
As the height increases, columnar grains change into equiaxed grains.
Equiaxed grains distribute at the intersection of these inclined columnar grains.
The number of layers containing columnar grains decreases as the laser power increases, and columnar grains turn into equiaxed grains as the height increases for all thin walls.

The structure of piezoelectric ceramics is perovskite and crystalline grain shows a block shape.
Antimony element partially controlled on the crystal field shift speed, and the crystal grain was more integrated.
It is obvious that the whole grains exhibit a regular shape and grain boundaries are very clear in Fig. 1(b).
The grain boundaries of the ceramic samples are unclearly at first and then increase with the increasing of sodium content.
When x=0.58, y=0.05, due to excess dope of Na, grains size is getting smaller, morphology irregular.

In this area, the grains are elongated towards the surface.
The size of coherent-scattering region X-rays of the grains of the c-ZrO2 phase is 15–20 nm.
The total number of pulses was N = 100 and 300.
It is seen that the shape of the grains in the melted subsurface region and that of the grains in the sample volume are radically different.
In the surface layers, the grains are oriented towards the surface to be treated.