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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.

The average grain size of TiNi coatings ranges between 60 ÷ 160 nm.
The process of formation of coatings was carried out in a specially designed technology (patent number 2430191), by the technology described in the patent number 2354750 (Fig. 1).
On (Fig. 4k) shows the electron diffraction pattern of the alloy TiNi, alloy mainly composed of randomly disoriented nanoscale grains.
The distribution of grain size in the surface layer of TiNi and percentages is shown in Fig. 5a.
Between the grains of austenite structure located intermetallics particles Ti2Ni are located.

Secondly sample was burnished by metallographic sand paper after from number 1 to number 5, follow-on used polishing compound polishing, Finally samples were corroded by 5% of nitric acid alcohol.
And it also changes grain boundary's status and decreases interfacial tension and interfacial energy.
Firstly, CeO2 segregates in grain boundary through Diffusion Mechanism, Because of segregation of CeO2 can purify segregation of the impurity elements in grain boundary, then grain boundary is strengthened.
Fig.3.a is a map about friction coefficient and numbering of samples, Fig.3.b is a map about wear rate and numbering of samples.
Fig.3.a Map about friction coefficient and numbering of samples, Fig.3.b Map about wear rate and numbering of samples It is shown that wear resistance of samples with adding CeO2 were better.

A special etching (CuSO4 + HCl) was also used to distinguish the grain structure.
The grain refining tests were performed on only one cutting temperature (590°C).
This is because a large number of nuclei are generated at low pouring temperatures, while at higher pouring temperatures it is impossible to produce a number of nuclei and the nucleation takes place during the first stage of the SEED process [6-7].
It seems that at higher pouring temperatures the addition of TiB2 does refine grain size, but this grain refining is not translated into a noticeable reduction of the α-Al particle size.
• The addition of TiB2 indeed reduces the grain size at all pouring temperatures.

Three microstructures such as a bimodal structure (B), a lamellar structure in small grains (Ls), and a lamellar structure in large grains (LL) were prepared.
LS (lamellar in small grains) 1000 (α + β) 1010 ˚C (α + β) / 3 h F.
LL (lamellar in large grains) 1080 (β) 1080 ˚C (β) / 3 h F.
In the Eq. 1, Lx and Ly represent the vertical or horizontal length of the SEM image, Nx and Ny represent the number of intersections with straight lines drawn vertically or horizontally, DSEM and DRe represent the scale bar length on SEM and actual images.
The decrease of stress exponent in the low applied stress level was found in B with grain size of 110 mm and LL with grain size of 550 mm, but it wat not found in LS with grain size of 90 mm.

The conventional Ti-6Al-4V had a grain diameter of 8 - 10 µm, whereas the fine grain had a grain diameter of 0.8 - 2.0 µm.
Fine Grain Ti-6Al-4V sample preparation conditions.
Alpha case thicknesses for (a) Superplastically Formed conventional grain and (b) as-exposed fine grain Ti-6Al-4V materials.
Depth of removal as a function of traverse rate for (a) Conventional Grain and (b) Fine Grain specimens.
[8] Hashish, M., et al, "Method and Apparatus for Fluidjet Formation, US patent number 6280302, August 2001

Together, these two aspects control grain refinement and homogenization.
Multiple layers or a thicker reinforcement phase can be used to increase the number of dispersions; however, multiple passes may be necessary for the proper breakup and uniform distribution of reinforcements.
The movement of dislocations may be harder, with a reduction in the grain size.
The addition of reinforcement particles, during FSP, may also aid in grain refinement; the existence of second phase particles (pinning effect) obstructs the direction of grain boundary which is migrating because of recrystallization and grain growth [10][11].
Grain size increases usually with increasing the rotational speed due to excessive heating and grain growth; conversely, Grain size decreases with increasing the traverse speed.

It is well known that submicron sized grains/ sub grains can be produced in most Al alloys using this technique.
The total strain accumulated in a material through a series of repetitive pressings, εN is given by [9], (1) where N is the total number of passes through the die.
In this paper, specimens have been designated as 2A, etc. where 2 represents the total number of extrusion passes and A represents the processing route.
The grain size of the initial solutionized material was approximately 15 µm.
After 3 passes, the grain size was reduced to 0.46 µm in route A ECAE and 0.55 µm in route C ECAE.

With nitrogen rate (168 kg/hm2), irrigation (90 mm) in jointing stage, and irrigation (70 mm) in heading stage, grain yield was higher.
Five factors were showed by capital letter (A, B, C, D and E) and four levels were showed by number in right hand of capital letter respectively.
It also showed that irrigation was main factor of improving and ensuring crop grain yield in arid region.
Therefore, the optimum combination of higher GY grain yield was A2C1D2.
Grain water use efficiency (GWUE) comprehensively reflected the relationship between water consumption and grain yield.

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.