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In the process of fine disperse grinding of powders a large number of new surfaces are formed and, as a consequence, there is a sharp increase in the specific surface, due to which powders become highly active [5, 6].
Group composition of oil sludge Asphaltenes Oils Resins 2,53 % 57,17% 40,30% Based on the theory of structure formation in asphalt concrete [17-19], the presence of a large number of oils in the surfactant will allow filling internal pores of grains of mineral powder with oil.
Analysis of microphotographs of mineral powders (Figure 2) revealed that the powder particles have an irregular shape with a large number of angles and edges.
Absorption Wave number, cm -1 Figure 3.
The analysis of microphotographs reveal that the surface of grains of a mineral powder is completely covered with a surfactant, and IR spectra prove the presence of chemisorption processes on the surface of grains of a mineral powder.

Flow stress, which is necessary for continuation of deformation is a function number of lattice defects, particularly of dislocations, and it can be expressed by the equation number, 2. 2 1 o bGk ρ ττ ⋅⋅⋅+= (2) where τo is value of initial flow stress, k is a constant, G, b is modulus of elasticity in shear, Burgers' vector.
Our target was to obtain after extrusion the semi-products with a fine-grain structure.
Obtaining of the necessary structure in extruded samples depends primarily on the tool's geometry, number of passes through the die, obtained magnitude of deformation, temperature.
Impact of the grain boundaries has also a very significant effect.
These procedure makes it possible to obtain the grain size of approx. 1 µm.

The basis of severe plastic deformation methods is to increase free energy of the poly-crystals and much more defects and interfaces (grain boundaries) in non-equilibria processes and eventually to fragment the grains up to 100 nm or less [2].
Fifth batch was subjected to severe deep rolling (SDRing) by increasing the pass number to 15.
The initial grains of the material can be easily recognized in the not-refined region.
Ultrafine grained/nano-structured surface layers up to 10-12 µm deep was produced after severe shot peening.
FWHM is related to the grain distortion (microstrain, type II) and grain size and can also be considered as an index of hardening.

Each cell represents 1μm×1μm in the real sample and has four state variables: a dislocation density variable, an orientation variable, a recrystallization number variable and a grain label variable.
As deformation continues, new strain-free nuclei will form on grain boundaries when ρ exceeds its critical value ρcr, For grain boundary bulging nucleation mechanism, a boundary nucleation rate I is defined as the number of new nuclei generated per unit time on per unit length of grain boundary with ρ>ρcr.
(7) Modeling of grain growth.
The white areas represent the primary grains and the colored areas represent the R-grains.
This suggests that fine-grained material provides sufficient number of nucleation sites, leading to relatively rapid rate of recrystallization.

Application: Drying of Lentil Grain.
points and is the number of estimated parameters [23].
This behavior occurs, probably due to the grain size, initial moisture content and the use of equilibrium boundary condition on the grain surface, as reported by Oliveira et al. [8,13,16].
Although the lentil grain is heated in approximately 50 s, the heat flux continues to decrease until 24 hours of the process, because a part of the provided energy is used to heat the grain and another to evaporate the moisture inside the grain.
The average temperature of the lentil grain quickly reached the thermal equilibrium due to the small grain size, high thermal conductivity and the equilibrium boundary condition used in the mathematical model.

Based on the rate-dependent crystal plasticity theory, the user material subroutine is embedded into the abaqus / standard, which is able to describe the changes of grain orientation.
As for the microscopic mechanism of the anisotropy of the sheet, many scholars have done a lot of research [1,2,3,4]and reults show it is because of the preferred orientation of the grains .
C3D8 element type is adopted to mesh the specimen and the number of elements is 510 .
The initial orientations of the grains are represented by two sets of vectors (-1,0,1,0,0,1,0,0) and (0,1,0,0,1,0,0, 0), assigned to the material integration points.
Further, from the point of view of the grain orientation and texture, the microscopic mechanism of necking is analyzed.

Usually, the overpotentials of Cu electrodeposition are relatively low [19], the number of formed nucleus is less in the process of electrocrystallization.
While the high current density of Cu electrodeposition gives the rapid growth rate of the primarily-nucleated grains to cone-shaped, this inhibits the growth of the following grains.
If the RE content achieves 9 mg/L (Fig.1d), however, with the increase of RE content, the grain microstructures of cooper foil display the coarser grain and inhomogeneous distribution.
So the RE can effectively inhibit grain growth and refine the grain of copper foil.
The grain refinement effect of additive is optimum with RE content of 6 mg/L

The results show that the cooling rate plays an important role in the ferrite grain size and the volume fraction of granular bainite.
It is found that the cooling rate greatly affects the grain size of polygonal ferrite and the volume fraction of granular bainite.
As the cooling rate increases, the ferrite grains become finer and less as shown in Fig.3(c).
With the decrease of cooling temperature, a great number of polygonal ferrite grains nucleate inside the austenite grain, and so the volume fraction of the polygonal ferrite increases.
Therefore, smaller grain can be obtained, as shown in Fig. 3(c).

The effect of the grain size on the velocity of the Lüders' band front is especially enlightened.
The effect of the grain size on the velocity of the Lüders' band front is especially enlightened.
The influence of grain size and in particular, the brake effect of grain boundaries on the Lüders band propagation, is well described as it can be seen in Fig. 3b.
The smaller grain size originates a higher YPE and consequently higher YS.
Grain Boundaries in Metals.

But in practice it is difficult to apply ECAP to CP-Ti where the number of active slip system is limited.
Grain refinement is achieved in all experiments but the measured grain size tends to increase with increasing pressing temperature [12,13].
ECAP was successfully executed at a conventional die and the number of passes was equal to 2.
Most grains became very clear and the average grains size is ~200 nm.
The top row is for initial material and remaining rows cover the different numbers of ECAP passes in two kinds of regime.