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There are a number of problems with the use of the phenomenon of superplastic, for example, the low productivity of the process due to relatively low strain rates.
There are grain -phase with a small number -phase - typical for an OT4-0 alloy, annealed at temperatures in the - region (Fig. 8,9).
The sizes of grain in all samples are within 10 ... 20 μm.
The length of the plate of -phase in the samples research is comparable to that of -transformed grain.
Development of fine-grain size titanium 6Al–4V alloy sheet material for low temperature superplastic forming.

Now it will be compared the texture prediction in samples deformed by tension with samples deformed by cold rolling mill for an area composed of 500 grains as opposed to one specific grain as previously presented.
Table 2- Number of variants with positive energy for each orientation.
For example, 4(a) is the result of transformation of 500 grains of austenite having Copper orientation with a spread of 20 degrees.
The model was solved for 500 grains with Brass texture, 500 grains with Goss texture, 100 grains with Copper texture and 100 grains with cube texture.
The number of variants generated was according to values presented in Table 2.

Solubility of sulfur in steel is minimum, it can combine Fe to FeS, and FeS and FeO can form a low melting point thermal brittle eutectic, FeS separates out in the grain boundary, which can decrease the strength and plasticity of slabs and produce the cracks on the grain boundary, so appropriate increase the Mn content to increase Mn/S can reduce the effects of sulfur hot brittleness on longitudinal crack[5].
Figure 13 shows the distribution of acid-soluble aluminium content, its content of most heats is excess of 0.035% which is the internal controlled component and some heats are more than 0.045%, the number of former is 34.
Fig.14 The distribution of tundish temperature Fig.15 The distribution of overheating degree From Figure 14, the distribution of tundish temperature is broad, the internal value of the plant is 1537~1557℃, the number of heats which is not in this arrange is 60 and accounts for 14.4%.
The results show that[7] an increase in superheat of 10℃, the flow of molten steel in mould will eat off about 2mm shell, some scholars considered that the high temperature slowed the nucleation rate of small equiaxed grains when molten steel of high superheat contact with inner mould, so the whole small equiaxed grains zone become thin and produce the scull fracture in the weak stress concentration[8].
The number of heats which their content of acid-soluble aluminium is over the intinal value is too large, alumina changes the composition and performance.of mould powder and has effect on the surface quality of slabs

As the temperature continues to increase, the content of equiaxed alpha decreases, and the grain size of the beta transformation increases.
Fig. 2 a) alpha phase volume number; b) Spherical /stripe alpha volume number; c) alpha phase grain size In order to quantitatively observe the ratio of the αp to the αs, the relationship between the microstructure and the properties is established.
It can be observed in Fig. 2 (c) that the grain size of alpha phase decreases with decreasing temperature.
At the same time, it can be seen that the silicide are obviously precipitated at the grain boundary, and the number of silicide is very small at 600 °C.
With this change, αs precipitates gradually, and the number of betat increases.

Hot tear initiates in the mushy zone and expands along the grain boundary, and the thickness of hot tear is inhomogenous, and the shape of hot tear is zigzag and irregular.
Additionally, there is no addition of grain refiners, such as Al-Ti-B, Al-Ti-C and Al-Ti master alloys.
During the conventional hot-top casting process, the microstructure of the ingot is very coarse, the dendritic space is big, and the average grains size is about 1100 µm.
During the LFE hot-top casting process, the microstructure of the ingot is fine, and the average grain size is about 300 µm.
The change of melt flow caused by the Lorentz force can promote the evacuation of superheat and increase the number of nuclei at the bottom of the sump, and the depth of the sump is decreased.

In contrast, MgAl2O4 spinel and MgO–spinel based refractories were investigated for a large number of applications as an alternative component of chrome-containing refractory[3].
The presence of periclase as a second phase restrained the grain boundary motion and produced dense, small grained body with superior mechanical characteristics.
This is due to the better sintering situation as the spinel grain size gets bigger, forming a good network structure and making the material dense.
It also produce a small number of liquid to move to the particles in the gap , make solid particles of the crystallization of a continuous nets and form the combination of the characteristic structure directly.
The presence of free periclase hinders and controls the grain boundary migration in specimen No.5.

The descriptions of the accident At 23:56,on February 22nd 2009 ,the control-center received alarm message and found a large number of water leaking from the 1st cylinder cover of C102B and the compressor with strong vibration.
The same time, the Fig. showed a large number of local and density pin-holes around there, some of which had formed micro-cracks along the boundary of the (a+Si) eutectic phase.
It showed that plastic of material dramatically dropped down since a large number of distributions of brittle phase Si crystal along the grain boundaries.
The phenomena that solid solution Al primary crystal grains were thick commonly caused by that, melting temperature were not carefully controlled ,thereby , liquid aluminum was overheating.
It can be seen a large number of secondary micro cracks along the grain boundary phase had formed.

The structure of solution treated alloys consists of almost uniform grains with a grain size of (40±6) μm in the WE43 and (520±230) μm in the Mg3Y3Nd alloy.
Its diameter does not differ essentially, but its number density is lower.
One can conclude in accordance to [10], that not only a volume fraction of precipitated phase(s) but also the aspect ratio and number density of precipitates determine the hardening effect.
Its form and matrix orientation are preserved, but the plate diameter increases simultaneously with a decreasing number density – Fig. 6.
The b phase plates disappear in grain interiors of the specimen annealed up to 480°C, grain boundaries only are decorated by incoherent rectangular particles (several micrometers large) of the body centered tetragonal (bct) phase of the Mg41Nd5-type [20, 21] and solute concentration in grain interiors already nears its value after solution treatment.

Magnetic compound fluid (MCF) is formed by mixing abrasive grains, α-cellulose, iron powder and Magnetic-Fluid together according to a certain proportion.
When the spindle speed is less than 200rpm, the number of abrasive grains colliding with the workpiece surface increases with the increase of speed, and processing efficiency is improved.
Within a certain range, the increase of the grinding pressure leads to the increase of the shear stress of abrasive grains, resulting in better machining efficiency and machining quality; but when machining gap is larger than the boundary value, the pressure between the workpiece surface and grinding fluid will be reduced.
Then the grinding force of abrasive grains declines, as well as the grinding processing effect.

Standard compression tests of the cubical prototypes of fine-grained sand concrete made of two brands of portland cement – PC400 and PC500 with different percentage of PET-fibers have been conducted.
The optimum content of PET-fiber, wherein there is a maximum increase of durability of fine-grained fiber-reinforced concrete, has been set.
This is due to a number of its advantages, such as low cost, availability of production technology, the possibility of application in different climatic conditions, as well as increased strength.
New Trends in Materials Science Experimental researches have been done to determine the optimal volume content of fibers ‘μ’ for fine-grained reinforced concrete.
The composition of fine-grained sand concrete with the compressive strength of B5 was designed previously.