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Coarse-grained, fine-grained fillers and fine powder are selected in such a way that the curve of particle size distribution is located in the zone bounded by the limit curves, and is as smooth as possible.
The grain composition of the mineral mixture is calculated depending on the number of selected raw mineral materials and their grain compositions [14-17].
The samples were taken and their grain composition and amount of bitumen was assessed when preparing asphalt mixes at an asphalt plant.
Tables 1-2 present the composition and the number of discrepancies in the composition of crushed stone-mastic asphalt concrete (SMA-20) and asphalt concrete type B I mark, respectively.
The compositions with the numbers 1-10 and 14-17 are for the fine-grained asphalt type B I brand, 1, 3, 5, 8-10 are for SMA-20.

However, the more excellent grain refinement of ECAE makes it preferred to other extrusion techniques [2, 3].
It was as well discovered that the ideal temperature to achieve the well define grain boundary is 350℃ with more number of passes.
This may be as a result of recrystallisation and grain growth at higher temperatures [9].
At high temperature, grain structure of most materials can be refined into ultrafine grain which is responsible for the enhanced properties observed [2, 21-23].
Equal channel angular pressing technique for formation of ultra-fine-grained structures.

Microhardness evolution as a function of pass number.
The microhardness evolution as a function of pass number is shown in Fig. 7.
Irrespective of material and pass number a similar microstructure evolution during annealing was evident characterized by the emergence of new larger grains in the deformed structure (Fig. 8a, b).
In general, the hardness decrease became faster with growing number of passes.
Apparent activation energy for discontinuous recrystallization vs. pass number.

The tensile deformation at 473 K led to the additional grain growth and formation of new grains.
In particular grain boundaries influence creep behaviour of ultrafine-grained materials because the increasing contribution of grain boundary sliding to the total creep deformation can be expected.
The high number of HAGBs in the microstructure in the connection with relatively small grain size probably lead to the higher activity of additional creep mechanisms like GBS, cavitation and more intensive diffusion processes.
Furthermore, grain boundaries can influence creep behaviour of ultrafine-grained materials due to synergetic effect of additional operating creep mechanisms like grain boundary sliding (GBS), intergranular cavitation or more intensive grain boundary diffusion [19].
Creep in ultrafine grained aluminium.

It is assumed that diffusing atoms may visit many grains and grain boundaries during a diffusion experiment Type A Kinetics Regime [9].
Smoluchowski, Theory of Grain Boundary Diffusion, Phys.
Herzig, Grain boundary diffusion: recent progress and future research, Mat.
Gust, Grain boundary diffusion: fundamentals to recent developments, Int.
Dillon, Scaling effects on grain boundary diffusivity; Au in Cu, Acta Mater. 61 (2013) 1851-1861

Due to a large number of the optimization parameters and variables the practical solution for rolling is difficult.
Such analysis requires great number of observations - hundreds of thousands measurements - to determine how individual parameters affects the result in the form of temperature and grain size.
The average grain size (Dγ6P).
However, we know that the most favorable grain size after hot rolling is 15-20 microns.
The rules to obtain the most favorable grain size after hot rolling.

So, the analysis of texture evolution in route Bc is highly dependant on the number of passes.
In addition to the number of passes, developement of texture and its relationship with shear plane existing at intersection of inlet and exit channel of ECAE die are main factors influencing the grain refinement occuring during ECAE process [6].
After N = 4 (Fig.1(d)), fragmentation of elongated grains is more complete with the fraction of ultrafine grains increasing.
The weakening of texture for N = 3 and N = 4 are the conditions where fine scale dynamically recrystallised grains were seen as the number of passes increases.
Bulk texture studies using XRD indicates that after N = 1, the value of texture strength decreases with increase in number of passes and texture is very weak after N = 4.

The grains and grain boundaries were not attacked at the beginning of the first peak -168 mVSCE and started to be revealed at 18 and 216 mVSCE in the potentiodynamic polarization test.
Stefec et al. [34] have conducted a systematic study of the pitting resistance of cold rolled specimens and reported a direct correlation between the level of deformation and the number of pits formed.
The signatures of grain fragmentation are noted from c) to f).
Randle, Sigma-Boundary Statistics by Length and Number, Interface Science, 10 (2002) 271-277
Randle, Twinning-related grain boundary engineering, Acta Materialia, 52 (2004) 4067-4081

The result evidently shows that the ultrasonic-assisted deformation has a meaningful influence on the grain refinement – the application of the USV enhances the formation of deformation bands and new sub-grains.
To date the evolution of microstructure has been the subject of a number of studies focused on cubic and hexagonal materials [11] [12] [13].
It is clearly seen that this shear bands nucleate at the grain boundaries.
The highest degree of grain refinement was observed in the centre of deformed area.
Sklenička, Grain and subgrain boundaries in ultrafine-grained materials, Mater.

The power of grain size was taken from a regression model developed previously that is able to predict the static recrystallisation kinetics of vast number of carbon and microalloyed steel grades.
It was reported that due to the pinning effect exerted by sulphur-rich particles, grain growth is delayed up to reheating temperatures as high as 1250°C, thus resulting in a fine austenite grain size prior to subsequent deformation.
No specific study was undertaken to vary the grain size and to estimate the grain size exponent (s) for two reasons: first, it is quite difficult to get large variations in grain size owing to the presence of sulphide inclusions, which retard the grain growth process up to at least 1250°C [2] and secondly, the grain size exponent has also been found to be strongly grain size dependent [8-10].
Hence, the equation developed for the grain size exponent (s) in the previous regression model [8-10] has been employed here in predicting the SRX kinetics.
Similarly, systematic relaxation tests carried out on a number of C/CMn steels yielded strain rate exponent values in the range -0.75 to -0.8.