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Numbers of readings were taken on each sample to obtain reasonable statistics relation to their hardness values.
In this present study, we calculated size of α grain, parameter of non-uniaxiality of α grain, percentages of α grain, number of α grain per unit area etc manually in a metallurgical microscope (ZEISS, AXIO VERT 40 MAT) taking each individual alpha grain into account.
There was similarity in microstructure with respect to number of alpha grains per unit area, percentage of alpha phase, average size of alpha grains, and parameter of non-uniaxiality of alpha grain at the necked portions while being the part was air cooled or water quenched.
At the head portion, difference in microstructure have been observed with respect to number of alpha grains per unit area, parameter of non-uniaxiality of alpha grain while being the part was air cooled or water quenched.
At the necked portions of the specimen, the microstructures were almost similar while being water quenched or air cooled with respect to number of alpha grains per unit area, percentage of alpha phase, average size of alpha grains, parameter of non-uniaxiality of alpha grain and micro Vickers hardness value.

Most of the matrix was found to be composed of fully recrystallized grains with average diameters around 10 microns.
Zones characterized by finer submicron scale grains could also be identified locally as well as grains containing networks of subgrain boundaries.
In their work they consider that the stability of carbides in steels decreases with the increasing element group number.
When measuring grain/particle sizes with EBSD [5] a grain/particle is defined by the minimum number of data points per grain, the threshold boundary misorientation angle and the step size.
Humphreys has shown that a minimum of 8 pixels per grain are required for an accuracy of 5% in determining the grain size [5] The results shown in figure 5 b) indicate that the VC particles are submicron sized with an average particle size of ~400nm.

Grain Size Distribution.
Figs. 5 (a) and (b), and Figs. 5 (c) and (d) show the number fractions and the area fractions, respectively.
Fig. 4 Change in pole densities of the compression plane at {011} and {001} with an increase in strain under three kinds of strain rate at 723K 0 1 2 0 2 4 6 8 True Strain, ε Pole Density 1.0X10 -4 5.0X10 -4 Al-3mass％Mg, 723K 001 011 strain rate /s -1 1.0X10 -3 0 200 400 600 0 10 20 30 40 Grain Size, d/µm Al-3mass% Mg, 723K As annealed Number Fraction of Grains (％) Total number of grains:211 Average grain size:115µm 20.4％ 0 200 400 600 0 10 20 30 40 Grain Size, d/µm Number Fraction of Grains (％) Al-3mass% Mg, 723K ε =1.0×10-3 s-1 , ε =-1.0 Total number of grains:222 Average grain size:109µm 39.6％ 0 200 400 600 0 10 20 30 40 Grain Size, d/µm Al-3mass% Mg, 723K As annealed Area Fraction of Grains (％) Total number of grains:211 Average grain size:115µm 23.4％ 0 200 400 600 0 10 20 30 40 Grain Size, d/µm Area Fraction of Grains (％) Al-3mass% Mg, 723K ε =1.0×10-3 s-1 , ε =-1.0 Total number of
(a) and (b) show number fractions and (c) and (d) show area fractions.
The number in the figure is the strains estimated by assuming the homogeneous deformation.

Electrodeposition has a number of advantages compared to other processes of producing thin nanocrystalline films, including the possibility of deposition of a large number of pure metals, alloys and composite materials with grain sizes less than 100 nm with no restriction on the shape and surface area for deposition, high performance, low cost and easy transfer of technology from the laboratory to mass production [5].
Nickel is a ferromagnet, which has been successfully electrodeposited on metal and semiconductor substrates with a grain size in the nanometer range.
In recent years there has been a large number of studies on the physical properties of nickel films and knowledge has been gained about the relationship of their structural, magnetic, electrical and mechanical properties [6-12].
As a result, it was found that the average grain size for all the films was 19.81 nm regardless of the film thickness.
[16] Herzer G., Grain size dependence of coercivity and permeabilityin nanocrystalline ferromagnets, IEEE Trans.

Dimensions of packets and blocks could not be determined with high accuracy due to the fact that a limited number of areas could be analyzed by careful orientation analysis [3].
Average size of these grains is ~2mm and, therefore, the 9%Cr steels are ultra-fine grained materials.
No remarkable changes in size and number of these carbides located along block boundaries were found.
This is caused by large Zener drag pressure on these HAGBs due to large number of the M23C6 carbides and Laves phase.
By contrast, minor normal grain growth occurs under creep.

Some grains contain annealing twins.
The numbered white boxes show the areas for detailed microstructure analysis presented in Fig. 3.
Figure 3 shows SEM images obtained from different areas of the weld (these areas are indicated by numbers in Fig. 2).
In area #1, a fine-grained microstructure with an average grain size 2.0±0.8 μm is formed after friction stir welding.
The contrast suggests that the particles were enriched with elements with high atomic number.

Under intense plastic deformation at elevated temperatures, the interstitial impurity concentration on and near the grain boundaries can vary, which naturally affects the ability of the grain boundaries to generate dislocations and also affects the resistance to motion of dislocations near the boundaries and inside the grains.
As a result of this pressing regime, a submicrocrystalline structure with average diameter of the elements of the grain–subgrain structure equal to 310 nm was formed for an initial (before pressing) grain size of 10 μm [2] Here the elements of the grain–subgrain structure have a preferentially equiaxial shape, and the fraction of large-angle grain boundaries stands at about 70%.
For both the submicrocrystalline structure and the coarse-grained structure, fracture is ductile.
In addition, pores are observed on the fracture surface whose diameter is less for the submicrocrystalline structure, and their number greater, than for the coarse-grained structure.
In particular, these can be grain-boundary sliding and vacancy creep.

But the impact property obviously decreased with the increase of quenching temperature, that is due to the grain coarsening.
A number of studies about the steel are reported so far.
On the one hand, carbides dissolved and more alloy elements diffused into austenite grains with the quenching heating temperature increased and heating time prolongated, that enhanced the solution strengthening and the grain boundary strength.
On the other hand, the grain and the martensite lath grew up with quenching heating temperature increased and heating time prolongated, that weakened the grain strengthening.
Fig.3 shows the average grain size after quenching at different parameters.

Quaternion is a number that extends the complex number, and can represent the three-dimensional orientation and rotation.
A quaternion is a number that extends the complex number and expressed as , where and are imaginary units satisfying the following relationships: (2) A quaternion can be considered as a number containing one scalar element and one three-dimensional vector element, so that a quaternion can express a three-dimensional rotation.
The both crystal grains grow isotropically.
When the crystal grains come in contact with each other, the grain boundary is formed due to the misorientation between two grains.
In contrast with the case 1, the grain boundary is not formed when the crystal grains come in contact with each other, and two grains merge into a single grain, because two crystal grains have the identical orientation.

The purpose of the research is to determine the effect of a mixture of water of different structure on the strength of fine-grained concrete and the speed of its formation.
However, the availability of such cements "on hand" in a significant number of cases is significantly limited and requires a solution to the problem of organizing their search and transportation in sufficient quantities.
The problem lies in the clearly insufficient number of existing methods of calculation, construction and organizational and technological measures to ensure the stability of concrete.
Aim of Paper The purpose of the research is to determine the effect of thermally activated water on the strength of fine-grained concrete and the rate of formation of its structure.
Shishkin, Research into effect of complex nanomodifiers on the strength of fine-grained concrete.