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And new particles are grow in intracrystalline and grain boundary.
After adding 2.4% Sm and 1.6% Nd, he grain size of AZ81 magnesium alloy decreases from 98μm to 77μm.
With the increase of RE, the size of grey block eutectic structure in grain boundary is smaller, and the number decreases.
Meanwhile, granular phases increase gradually in intracrystalline and grain boundary.
Grain size reduces from 98 μm to 77 μm

Obviously, the pulse deposited grain size exhibits a reverse relationship with current density (i) and over-potential (η).
Therefore, the grain size could be controlled through precisely adjusting the pulse parameters such as output pulse frequency and duty cycle.
Fig. 1 illustrates the practical relationships between the average grain size and the electro-deposition parameters [8].
That is to say, at initial stage, the carbonaceous gas decompose on the front-exposed surfaces of the nickel (Ni) or iron (Fe) metal nano-grains when carbon atoms are dissolved in the nano-grains.
A number of processes have been developed for growing 1-D metal oxide nano-materials, such as CVD; thermal decomposition of precursor, template, thermal oxidation of pure metals, etc.

Influence of different abrasive belt speed to grinding efficiency.As shown in Fig.3: The maximum grinding ratio can be got with the belt speed 19m/s,the surface roughness becomes smaller with the increase of the linear speed,And the grit number increases in the grinding zone per unit time with the increase of belt speed. that is to say,the number of effective cutting edges is increasing.When Vs increases to a certain extent, the dwell time of single grain cutting edge becomes shorter in grinding zone.
The grit number increases as the grinding pressure increases with low pressure.
Influence of different grain size to grinding efficiency.
The grain size is the main factor to influence surface roughness.
As shown in Fig.5,the surface roughness reduces as the grain size increases. the falling process of surface roughness becomes fast when the grain size is between 80~120#,and the falling process of surface roughness becomes slow when the grain size is between 120~180#.

The number of times was then noted down.
During process of decarbonizing, carbon atoms are firstly segregated to grain boundary, and then diffuse to surface along grain boundary under condition of oxidation atmosphere.
The phosphorus have few sites to segregate at grain boundaries.
The carbon atoms escape from the inside and grain boundary, remaining large amount of vacancy sites, promotes the segregation of phosphorus to grain boundary.
Therefore, the grain boundary has no carbon segregation, only P segregation at grain boundary, as shown figure 5a.

In order to enhance the material’s strength, refining the prior austenite grain size through repeated heating has been investigated.
In the QTQTQT specimens, the grain size was approximately 5-10 μm (Fig. 5(a)).
The grain sizes were approximately 15 mm (Q1T1) and 7 mm (Q3T1).
Figure 7 shows the modified S-N diagram based on the stress amplitudes at the crack origin depths to the number of cycles.
The number of crack origins of Al2O3 was two, and that of TiN is five in the QTQTQT samples.

According to modern concepts of the mechanism of plastic deformation the strengthening effect is a consequence of increasing the number of deformed grains and growth of grain boundaries [1].
In the first series of experiments each was is deformed in ECAP channel matrix at 25°C with quadriplex number of passes and the selection of samples to analyze after each pass.
It is equipped with a set-top box to determine the micro hardness separated phases, set-top box for automatic microphotography of microstructure, as well as software to determine the points of grain and the number of phases.
The evolution of homogeneity and grain refinement during equal-channel angular pressing: A model for grain refinement in ECAP // Materials Science and Engineering. 2005.
Developing stable fine-grain microstructures by large strain deformation // Phil.

Half numbers of samples were solution treated at 900 °C for 2 hrs and remaining were aged at 600 °C for 3 hrs.
Introduction Nickel Titanium shape memory alloys are mostly used in large numbers of technological fields due to their superiority over other shape memory alloys [1-3].
After solution treatment half numbers of samples were aged at 600oC for 3 hours in the same manner as solution treatment.
However, there was no evidence of precipitation on the grain boundaries as well as in the grain interior due to the aging effect.
Increase in hardness in both alloys is suggested to be the result of precipitates formed in the alloy along the grain boundaries and grain interiors. 4.

Graining image from high speed video recording was shown in Figure. 1.
A dimensionless correlation has been announced by Hu[6] in 2008 derived as follows: (3) Where ds is dimeter of the slag particle, t1 is the thickness of liquid slag film, Re is Reynolds Number, Sr is Strouhal Number, and We is Weber Number.
Liu et al. study the mechanism of slag graining using a mixture of water and glycerol for analogue experiment in 2012.
Graining image from high speed video recording was shown in Figure. 1.
With the deepening of the study an increasing number of people begin to try commercialization.

However, the embeddedness and medium diameter of the grain varied within the area which tend to affect the spawning site selection of the fish.
As the recruitment number of the fish filial generation is highly correlated with the natural spawning activities of the adults, it is significantly important to study the riverbed substrate so as to improve the spawning activities to produce more eggs, which will be significantly meaningful for maintaining and rehabilitating of this species.
The embeddedness of the left 15 sampling sites was 32.0±26.9% (range 0−90.0%), and the medium diameter of the grain was 25.5±10.9 cm (range 8.0−40.0 cm).
The area with higher hardness means lower embeddedness, and the area with higher roughness means higher medium diameter of the grain.
However, the embeddedness and medium diameter of the grain varied within the area and probably would affect the spawning site selection of the fish.

Orientation gradients formed in γ oriented grains across a single grain are around 5° to 30° and this orientation difference is sufficient to form nuclei with mobile interfaces during annealing and hence to create chains of γ oriented new grains in the original hot band γ grain envelopes.
Compared with the γ oriented grains, the α deformed grains contain only small lattice curvatures, and therefore in-grain nucleation is rare, these grains are mostly consumed by invading γ grains toward the end of the recrystallization.
When the holding time is 10min (Figs.2 (b), (d) and (f)), the number of the recrystallized nuclei in the non-field annealed specimen is much more than the field annealed specimens, even though there are some abnormal growth grains in the field annealed specimen (Fig.2 (d)), which may indicate that the magnetic field retards the recrystallization process.
Usually, the CSL grain boundaries have lower interface energy than the random grain boundaries.
In this case, the grain boundary between newly formed nuclei and the deformed matrix is the low-energy ∑3 CSL grain boundary (60°<111> relationship). ∑3 CSL grain boundary has lower interface energy than ∑13b CSL grain boundary, so its formation is favored in energy.