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When the cooling rates are 0.5 ~ 3 ℃ / s(Fig. 3 (a), (b) and (c)), it is beneficial to the spread of iron atoms for the slower cooling rate. the grains are larger because of the slower nucleation rate and the higher growth rate.
When the cooling rates are 10~ 25 ℃ / s（fig. 3（e）~（h））, due to the larger cooling rate, higher degree of undercooling and larger nucleation rate, the number of nuclei in per unit volume relatively great, the room for every grain to grow smaller, so the grains are smaller.
With the increase of the cooling rate, grain size decreases gradually.
Widmanstatten structure will not influence Mechanical properties obviously through refining grain reasonably[6].
For the Si steel, the number of bending and blanking workability are decreased due to the increased hardness; but the very low hardness could lead to lamination burrs increase and inaccurate lamination dimension.

A constant speed of 50 mm/s was utilized for the specimen movement and the Almen intensity of the used setup was determined using different number of passes resulting to a value of 358A.
Some annealing twinning is also identifiable from the IPF map on the 316L grains.
The material has no texture as the grains do not have any preferred orientation.
The amount of grain boundaries have increased considerably at the very surface indicating that grain refinement has occurred.
While the number of grain boundaries has increased throughout the material, it appears that the SSP treatment has had a more severe impact on the copper areas as the amount of grain boundaries is higher on the green area.

The tensile stress around nanometer silicon carbide particles in alumina grain can be transferred to grain boundary and then compressive stress can be formed to strengthen grain boundary.
It is clear that the addition of nanometre SiC particles had a pinning effect on the growth of alumina grains and inhibited the grain growth, the alumina grain size gradually decreased as the content of silicon carbide increased, from about 10 μm of AS2 to about 2 μm of AS10.
The failure mode of grains in AS10 material is almost transgranular fracture.
Moreover, more nanoparticles will enter the alumina grain, leading to reduce grain boundary compressive stress, decrease alumina grain strength, and microcracks will cause a large number of particles to break through the grain.
In terms of crater size, the AS5 shows good bulletproof performance because it dissipates the energy of the bullet with a large number of deflecting microcracks, but also disperses it around the crater with radial cracks.

China's grain outputranks first in the world for 20 consecutive years, shown in Figure 1.
From the increasing number of machines it can be seen the influence of combine harvesters for agricultural production in China is growing [2].
Depending on grain feeding methods, it can be divided into full-feeding combine and semi-fed combine [6].
Cyclone Cheongju new election system and on the application of micro-grain combine harvester [D]. ​​
Combine the quality of grain analysis [J].Agricultural quality and supervision, 2009,06: 28-31 + 19

The crystal grain size was 60 nm.
The crystal grain size was 80 nm.
The crystal grain size was 80 nm.
Grains stack uniformly at low level doping.
When Co doping content reached to 5%, the number of the entrained space charge and oxygen vacancy of BiFeO3 thin films crystals were the biggest.

The main effect that contributes to this defined x concentration of substitution are the variation of the number of electrons in the 3d band, the change of the interatomic distances and the Mn-O-Mn bond angles.
Unsubstituted Pr(x) sample, P1 possess clear grain-grain-boundary region with bigger grain sizes.
The formation of LaPrBaMnTiO3 crystallites grain growth is not homogenous under this solid state condition for this sample.
Fine, agglomerated grain crystallites are observed in sample P5(x=0.07) in Figure 1(e).
The enhanced magnetic property in sample P5 is due to the fine grain microstructure.

And cerium is one of the most used alloying elements in Mg alloys because it has obvious refining effects on the grain size of Mg alloys [7, 8].
In addition the process of rolling deformation alloy β (Li) with the occurrence of dynamic recrystallization, it is small formed by equiaxed grains, and recrystallization grain size has decreased with increasing reduction(Figure 1(e), Figure 1(f)), The reason is that as increasing the degree of deformation Grains dislocation density is increase, lattice distortion increase , stored energy of nucleation-driven increase, so that the new increase in the number of grain nucleation can refine grain b.
Alloy performance improvement was mainly due to deformation strengthening and grain refinement.
Using CuKα-ray, Tube voltage 40 kV, Current 100 mA. measuring the density of grain-oriented (0002,, ,(110), (200), (211) crystal face by reflection method.
In addition the process of rolling deformation alloy β (Li) with the occurrence of dynamic recrystallization, it is small formed by equiaxed grains, and recrystallization grain size has decreased with increasing reduction. 2.

There are a large number of – type- conjugate bond and circled construction exist in carbon-nanotubes-material structures, which can be blended more easily than it do with other material scaled in nanometer.
It can be learnt that if the proportion of carbon-nanotubes-material in asphalt and SBS grains changes, so do the results.
When proportion of carbon-nanotubes-material in SBS grains is less than 0.02%, the asphalt modified little, and then the more the proportion of carbon-nanotubes-material in SBS grains, the better the performance of the asphalt modified with proportion of carbon-nanotubes-material in SBS grains, and when proportion of carbon-nanotubes-material in SBS grains is more than 4%, the more, the worse.
As results, the proportion of carbon-nanotubes-material in SBS grains can be comfortable between 0.02%~0.08%.
(2) Plain asphalt modified with SBS can improve it performance by adding agent carbon-nanotubes-material, and agent carbon-nanotubes-material have to mix with SBS grains to play an important role, and SBS grains have to be the key match in asphalt.

Besides some light-colored area along the grain boundaries could be clearly observed compared to the darker matrix area.
In the SEM picture (Fig.1) flower-shaped and granular second phases could be seen either inside grains or along the grain boundaries.
Map analysis of EDX proved that the boundary area had more Al element than the area inside the grain.
Very fine and equiaxial grains were observed in SEM (Fig.3c), which indicated that the equiaxial grains formed mainly inside the original grains and their size was about one twentieth of the original ones.
They are quite heat-resistant and almost keep unchanged in terms of morphology, distribution and number.

Grain is extremely fine and uniform (average grain diameter 15-16 micrometres corresponding grade 9 according to ASTM E112).
Change is marginal partial recrystallization phenomenon with the advent of a new generation of grain.
Echiaxi ferrite grains and small amounts (about 5%) of lamellar pearlite (X5000).
As a result of the comparative microscopic analysis of the pieces ( base material , heat affected zone , the cut zone) cut in water bed, the following can be observed: partial recrystallization, with the advent of even finer grain than base material grains, grain growth to depth of 100 μm on the edges, sometimes even looking martensitic, in the areas where the temperature was higher, and also a reduced HAZ is obtained.
Vasil'ev Plasma-arc cutting – a promising method of thermal cutting, 2003 în WELDING INTERNATIONAL Volume 17, Number 2, 147 151, DOI: 10.1533/wint 3096 [4] R.