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Although a number of research works have been carried out to study microstructure and texture evolution in normal IFHS steels, the development of crystallographic texture and microstructure during different annealing routes in the new type steel sheets has hardly been discussed[4].
After annealing, the ferrite grains are turned into polygonal grains, which are fully recrystallized.
Although both the samples are in an annealed condition and show recrystallized grains only, the CA sample is made up of large equiaxed grains of almost uniform size, whereas the BA sample shows a duplex grain structure, consisting of both large and small-sized grains.
Although the microstructure is fully recrystallized, it contains both equiaxed grains and grains that are somewhat elongated along RD.
The stored energy criteria may explain the preferred nucleation of the γ-grains[7,9].

Then, the properly performed metal forming process can improve the RT ductility both by grain size refinement and texture formation.
The material of ingots was non-homogeneous with an average grain size of ~300 µm and remarkable porosity in the center.
Also a remarkable number of oxide inclusions was observed as the remains of powder technology.
The average grain size of the material obtained by the SHS route was ~5 µm.
This phenomenon is rather the effect of the texture than the resulting grain size but the grain size of the material before extrusion could be the important factor of creation of the texture during this metal forming operation.

According to Scherrer equation, the average grain size is calculated as shown in Table 1.
It shows that as the distillation time increases, the average grain size grows bigger.
Because of the slow heating rate and uneven heating, the dehydration isn’t enough, so there may still have a large number of free water molecules on the precursor, forming the agglomeration between the nanoparticles.
The prepared ATO nanoparticles have smaller grain size and better crystallinity.
As the distillation time increases, the average grain size increases, but the colour fades.

Fei denotes the interstitial iron concentration, D the diffusivity and n the number of iron atoms in a precipitate.
The number of possible precipitation sites is given by N0 =DL/lp.
The number of precipitates (per cm 2) with a radius > 35 nm in a 30 µm thick slice is also shown in (c) (solid line).
Grain boundaries and grains with high DL density have a remarkable lower Fei concentration than good grains.
Therefore grains have a lower Fei concentration compared to the adjacent grain boundaries and other extended defects.

In the article the questions of application of a steel fiber for disperse reinforcing of fine-grained concrete are considered.
Introduction Today in Russia the use of composite materials is one of the most important and effective directions in construction owing to the increasing volume of constructions with the changed functions and need of increase in number of floors at reconstruction of the available buildings.
The types of steel fibers: а – flat milled; b – anchor; c – wavy The concrete matrix for all types of fibers was made of one composition of fine-grained concrete given in the table 1.
[10] Klyuyev S.V., Klyuyev A.V., Sopin D.M., Netrebenko A.V., Kazlitin S.A., Heavy loaded floors based on fine-grained fiber concrete, Magazine of Civil Engineering. 3 (2013) 7–14
[19] Lesovik R.V., Klyuyev S.V., Klyuyev A.V., Netrebenko A.V., Yerofeyev V.T., Durachenko A.V., Fine-Grain concrete reinforced by polypropylene fiber, Research Journal of Applied Sciences. 10 (10) (2015) 624–628

The increase in the band-gap in the case of the GB is 28%, and in the calculations, due to the constraints arising from the number of atoms that may be simulated in the quantum-chemical approach, the bulk-silicon region between boundary planes is around 3 nm.
Grossman, "Grain boundary engineering for improved thin silicon photovoltaics," Nano Letters, vol. 14, no. 9, pp. 4943-4950, 2014
Ho, "Finding the low-energy structures of si [001] symmetric tilted grain boundaries with a genetic algorithm," Phys.
Wolf, "Correlation between atomic structure and localized gap states in silicon grain boundaries," Phys.
Tsurekawa, "Electron-beam-induced current study of grain boundaries in multicrystalline silicon," J.

As can be seen in Fig. 1, R100 material is composed of coarse grains with average grain size of 170 microns.
In order to detect fatigue cracks at an early stage and to determine the crack growth behavior, replicas of the specimen surfaces were made during the fatigue process by interrupting the test at a fixed number of cycles.
In general, cracks are known to be blocked and to be deviated by grain boundaries due to their higher hardness at the grain boundaries than at the interior of the grain.
Extrusion direction 100 µm 103 104 105 106 107 108 75 100 125 150 175 200 Stress amplitude σa (MPa) Number of Cycles to failure N f (cycle) ：R100 ：R10 Nan's data (R20) Fig. 2 S-N curves for R10 and R100 materials in laboratory air.
The relationship between fatigue limit and grain diameter.

Dependence of the average (averaging was done according to five samples) number of cycles up to failure N on density of electron beam energy ES.
It is seen clearly that in the initial state a commercially pure titanium of grade VT1-0 is a polycrystalline material with the average grain size of D = 25 µm.
First, the average grain size (Fig. 3, b, c) decreased significantly to D = 8.3 µm.
Second, in the volume of grains the substructure of lamellar type (Fig. 3, b-d) is revealed.
The feature of this layer is the presence of large number of microcracks and micropores; and the sizes of pores vary from 0.1 µm to 0.3 µm (Fig. 4, d, micropores are designated by arrows).

The minimum grain size achieved is , however, dependent on a number of process variables as well as properties of the element, alloy, or compound milled.
Evidence for smaller nanocrystalline grain sizes formed by milling at low temperatures have now been observed in a number of materials including the intermetallic compound CoZr [15] and elemental Zn [16].
The fact that the average grain sizes of the samples cryomilled 1 and 2 h increase after room temperature milling is apparently due to the reduction in the number of the smaller grain sizes to bias the distribution to a larger average value.
National Science Foundation under grant number DMR-0201474 and the U.
Department of Energy under grant number DE-FG02-02ER46003.

The deformation zones within the austenite grains were formed.
Not only the grain boundary area and ferrite nucleus density increased, but also a large number of tiny ferrite grains appeared in the deformation zone, resulting in better strength and toughness.
The grain size at 1 / 4t was 10 level, while the size at 1/2t was 9.5 level. 1/2t 1/4t Fig. 2 Optical microstructure of FH40 steel Grain refinement at the first rolling stage occurred due to dynamic recrystallization.
The ferrite was in the form of equiaxial grains and narrow bands decorating the boundaries of coarse bainite grains.
Ultrafine Grained Steel: The Refinement Theory and Controlled Technology of Steel.