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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.

Structure and size of grain.
Heating speed and grain size.
After water cooling the structure consists of a small number of proeutectoid ferrite, martensite and bainite [16].
Ferrite development occurs at a border of fine-grained austenite due to a fast cooling and elastic stress occur at bainite and martensite crystals development in this ferrite will be increased number of locations [17-18].
Number of cycle Grain size, [microne] 1 35–40 2 12–17 3 5–10 Upon completion of third cycle the pipe were heated up to 500°С in order to provide a proper steel grade and stress relief arising as a result of accelerated cooling.

These small crystal grains exhibited textured structure when the electrolyte contained an organic sulfonic catalyst.
Thick black lines correspond to micro-cracks, and thin white lines correspond to grain boundaries.
Number of cracks formed during electroplating roughly increase with the amount of catalyst.
These results are consistent with the results by OM observation, and number of cracks formed during electroplating increases with the amount of catalyst.
(4) Number of surface cracks formed during electroplating roughly increase with the amount of catalyst.

Attachment and leaching test with pyrite grains.
For the attachment and leaching assays on pyrite grains, crushed pyrite was wet sieved and sterilized as described [9].
Flasks were incubated at 65°C with shaking at 120 rpm. 1 mL samples from supernatants were taken periodically and pH, ferric and ferrous iron as well as planktonic cell numbers were determined [4].
Similar results were obtained in attachment tests with pyrite grains.
No significant changes in the number of planktonic cells were observed during the experiment.

For both values of the wall thickness the hardness increased with rotational speeds and the number of revolutions.
The grain refinement starts at the inner surface of the sample and the width of the grain-refined zone grows with the number of revolutions.
The level of distortion of these grains is also larger for the higher rotation speed.
For a larger number of revolutions, even for a lower rotation speed, the front of the grain-refined zone penetrates deeper, almost through the entire wall thickness, cf.
With the growing number of revolutions ultrafine grains were observed near both surfaces of conical strip.

Tensile tests are conducted on a number of specimens.
There are a lot of large grains looking like cauliflower about 5-6µm which comprise many small grains about 200nm in Fig.2.
It can be seen that the average grain size on the surface of NO.2 increases significantly compared with that of NO.1, whose average grain size is about 600nm (see Fig.5).
There are many micropores at columnar grains boundaries of NO.1 (see Fig.4).
Average grain size on the surface of NO.2 is larger than that of NO.1.

Structural-Phase State of the Interphase Boundary at Thermal Diffusion Metallization of Diamond Grains by Cr and Ti P.P.
Metal powder Grain size [μm] Chromium 3-5 Titanium 120-125 In order to study the microstructure, morphology, the chemical composition of the metallized diamond grains and the diamond-coating interphase boundary, the scanning electron microscopy (SEM), X-ray spectroscopy and diffraction methods were used.
The numbers on the images indicate the points where the chemical composition of the coating was measured by the Energy-dispersive X-ray spectroscopy (EDX) method.
Whereas, the coating metallized by titanium has a layered and non-uniform in grain size and homogeneous in elemental composition structure.
Agren, Sintering shrinkage of WC-Co materials with bimodal grain size distribution, Acta Materialia. 53 (2005) 1665–1671

r( eM +σ⋅=ε ), and )r(B and )r(b are the stress concentrations tensors of grain (r), i.e. )r()r()r( bB +Σ⋅=σ , (3) where )r(σ is the average stress of grain (r).
Each of these polycrystals has associated different first- and secondorder moments of the stress field in the grains.
This is the reflection of an effective softer behavior at grain level that occurs when field fluctuations are considered for the determination of the linearized behavior of the grains.
For comparison between the different SC approaches, Fig. 2 shows the compression texture evolution (in terms of the basal texture factor along the axial direction), the effective stress, the relative basal activity, and the average number of active slip systems per grain, for the case of an initially random ice polycrystal, under the assumption of bas20pr τ×=τ and bas200pyr τ×=τ , where basτ , prτ and pyrτ are the critical stresses of the ( ) 11200001 basal, { } 11201010 prismatic and { } 11231122 pyramidal slip modes, respectively, as reported in [11].
However, at around 0.8 strain, the tangent results show a sudden drop in the basal activity, together with an increase in the effective stress (not attributable to geometric hardening only) and in the number of active deformation systems.

When the extrusion temperature is up to 390°C, the grain size increases significantly, but the second phase precipitation along grain boundaries transforms into continuous and uniform-distribution precipitation within the grain.
When the temperature is 300ºC, big grains in magnesium alloy form new grains under the influence of stress; at the same time, relative rotation among grains causes imperfect dynamic recrystallization of the deformed structure, which eventually forms fine particles.
At 330 ºC, some black second phase begin to precipitate along the boundary of the grains.
Since the pinning effect of the black second phase on the grain boundary prevents the grains from growing big, the grains becoming finer, which accounts for the increase of tensile strength.
When the extrusion ratio is 60, the grain has the smallest size (being about 3-5μm), the second phase in diffusion precipitation refines gradually and increases in number, and the tensile strength reaches to its highest.

Finishing polishing was performed on Al2O3 paste with grain size 0,25µm.
The results of the size measurements of the QE22 grain Parameter symbol unit QE22 - unmod.
QE22 - mod. acc. to MEL QE22 - mod. +50% QE22 - mod. +100% grain size area of flat section A [µm2] 9229 2484 774 543 number of grain per unit area NA [mm-2] 106 395 1274 1808 relative area of grain boundary SV [µm2/µm3] 0.026 0.048 0.084 0.105 heterogeneity of the grain size variation coefficient A ν(A) [%] 102 83 81 77 grain shape shape factor ξ - 0.635 0.662 0.662 0. 644 elongation factor δ - 1.64 1.67 1.78 1.65 Table 5.
The results of the size measurements of the RZ5 grain Parameter symbol unit RZ5 - unmod.
RZ5 - mod. acc. to MEL RZ5 - mod. +50% RZ5 - mod. +100% grain size area of flat section A [µm2] 7207 871 589 534 number of grain per unit area NA [mm-2] 135 1132 1669 1837 relative area of grain boundary SV [µm2/µm3] 0.029 0.084 0.103 0.110 heterogeneity of the grain size variation coefficient A ν(A) [%] 91 72 73 70 grain shape shape factor ξ - 0.627 0. 582 0. 617 0. 605 elongation factor δ - 1.59 1.69 1.63 1.62 a) b) Fig. 3. a) the results of the mid area plane section measurements of the grain, as well as the volume fraction of the eutectics with the variant of modification for QE22 alloy, b) the results of the average area of plane section measurements of the grain, as well as the volume fraction of the eutectics with the variant of modification for RZ5 alloy.