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The influence of the plasma parameter on both the melting depth and the grain size was discussed.
Secondly, it prevents grain from growing leading to obtain the fine grain, which is less than 6µm.
Salt spray test exhibits that pits were appear only after 16 h for plasma surface-modified AM60 sample, and the number of pits becomes more and more after 48 h.
Surface micro-hardness is enhanced by grain size strengthening and solid solution strengthening.
The micro-hardness of the melted layer is up to 160-200 HV0.05 by grain size strengthening

After deformation to a strain of 0.2, many grains can be seen to contain multiple twins and a small number of DRX grains can be observed to have formed at original grain boundaries.
In some regions, the "necklaces" of DRX grains decorating the pre-existing grains, and DRX grains associated with twins, have broadened considerably.
The SRX grains seemed to grow within the twinned region at a greater rate than in the original grain.
Larger original grains can be seen to be subdivided by twins that were previously filled with SRX grains but now contain DRX grains.
Instead, the colonies of DRX grains become stabilised and unrecrystallized grains remain.

An increased number of BCC phases resulted from high laser scanning speed.
However, when the scanning speed increased to 1.2 m/min, the number and size of pores decreased.
As the power level grew to 2200W, the number of cracks found decreased even more.
This is further corroborated by the improved microstructure and decreased number of visible macro fractures.
The number of cracks found decrease with increase in laser power.

Thus magnetic electrodepositing which has the advantage of less polluting as a new electroforming process comes into being[6].And numbers of research scholars have paid a great deal of attention to it[7-9].
And the grain nucleation rate is less than the growth rate.
So the grain of the nickel electroforming layer is refined.
As the magnetic intensity increases to 0.6T, the circular grains of the surface are evenly distributed, with the average grain size of 0.89μm.
With the increase of magnetic field intensity, a large number of nano particles can be uniformly deposited on the casting layer to improve the nucleation rate, in the function of grain refinement.

According to the Eq. 1 and Eq. 2, the average equivalent diameter of the globular grains is about 94.39 μm, and the shape factor of the globular grains is 0.80 [8].
The microstructure exhibits typical semi-solid structure with globular grains.
(1) (2) where D, SF, A, N and P are average grain size, shape factor, area, the number and perimeter of solid grains, respectively.
The globular grains are surrounded by lamellar structures.
Hardness in the primary solid grain area is about 330 HV.

The initial coarse grains of Ti-50.9at%Ni were obviously refined after eight ECAE processes.
Effects of pressing number on the transformation behavior have been investigated in detail.
Good one way shape memory and superelasticity were obtained for the submicron-grained Ti-50.9at%Ni alloy.
After eight passes ECAE, the microstructure was further refined and it was difficult to recognize the ultimate grains or grain boundaries under optical microscope (Fig.1c).
Good one way shape memory and superelasticity were obtained for the submicron-grained Ti-50.9at%Ni alloy.

Fig.1 shows the clustered sand grains movement track.
This SUFA will take off only the sand grains which are satisfied critical velocity value of sand grains to jump.
With this contrary, on the sheltered lee-face, the sand grains have lots of open air and sand grains respectively relax, so fly far.
In this study, for the numerical simulation, the average clustered sand grain field density (2.65 g/cm3) and air stream field density (0.00129 g/ cm3) are assumed to be constant, and the average clustered sand field grain size and shape are set by the random number during the simulation in the whole field, then the whole sand field surface roughness are obtained automatically by using this manner.
However, for the detailed analysis needs to consider concrete influence factors and number of simulations results and should be compared with experiment.

EBSD mapping shows that the 'new' grains appear first on the boundaries of deformed {111} grains and have high angle misorientations with the deformed grains, although the new grains are also of {111} type. {111} type deformed grains are recrystallised first due to their higher stored energy relative to {001} grains.
The as deformed microstructure is characterised by elongated grains of the {001} and {111} type (Fig 3a), the {111} grains show a large number of subgrain boundaries with the subgrains being generally quite small, <5µm in diameter.
They mostly occur on grain boundaries between the {111} grains and the {001} grains, and as they grow they consume the {111} grains.
However we can say that: • {111} grains with HAGBs nucleate on the grain boundaries of deformed {111} grains
• {001} grains remain for longer during the anneal than {111} grains because of their relatively low stored energy. • {001} grains tend to be consumed by new {111} grains rather than nucleate new {001} grains

We found that, with increasing temperature, Zr impurities become more stable and prefer to segregate at the interface of ∑5 (310)[001] grain boundary.
Several preliminarily calculations were made in order to estimate the required number of layers.
Following these energy convergence calculations, it was estimated that 20 layers parallel to the grain boundary plane were required.
Further information about the modeling of the ∑5 grain boundary can be found in [12].
The calculated impurity formation energies for substitutions at the grain boundary interface ∑5 (310) [001] are given in Fig. 3.

Macrostructure of the alloy is changed from coarsened grains to complete fine equiaxed grains.
Meanwhile, mechanism of grain refinement was also discussed.
The average grain size was measured by the linear intercept method.
Comparatively, crystalline fining grain can restrain the cleavage fracture, there are many tear ridge in the fracture of sample with AC magnetic field treatment, and the number of brittle batten decreases obviously, which is the typical quasi cleavage fracture, as shown in Fig.9 (b).
Macrostructure of the alloy is changed from coarsened grains to complete fine equiaxed grains.