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Conductivity studies indicate that the total conductivity is dominated by the grain boundary.
Infrared spectra were recorded in the form of KBr pellets in the wave number range 4000–400 cm–1 using Nicolet Avatar 360 FT/IR Spectrometer.
The conductivity decreases with the increase of the grain boundary (Rgb).
This proves that the total conductivity is dominated by the grain boundary[10].
Complex impedance plots of the samples show the total conductivity is dominated by the grain boundary.

HA coating transformed for 5 days in the SBF consisted of densely-packed rod-shaped crystallites with various differentiated grains.
Octacalcium phosphate (OCP) and HA coating transformed for 5 days in the culture medium consisted of both flake-shaped and rod-shaped crystallites with indistinct grains.
The coating transformed on the H2O2-treated titanium substrate after electrodeposition and subsequent immersion in the SBF for 5 days was consisted of uniform and small rod-shaped crystallites with clearly distinguished grains.
The coating transformed on the H2O2-treated titanium substrate after electrodeposition and subsequent immersion in the culture medium for 5 days consisted of both flake-shaped and rod-shaped crystallites with unclear grains.
After 5 days culturing, the cells were spread more flatly with the increase of the number of the cells.

Neutron diffraction was used to measure residual strains at a number of positions along a series of 5 overlapping FTS welds.
The thin plasticized layer continually forms, shears and welds to produce a rising fine-grained weld metal pillar, as the tool is plunged downwards and consumed.
Fig. 5b shows the lower temperature heataffected zone (HAZ) of fine-grained bainite, Fig 5c depicts the high temperature HAZ comprising coarse grained bainite and Fig. 5d shows the weld metal which has a bainitic structure with spheroidal carbides.
Depth Below Surface Vickers Hardness HV30 kgf Line A Line B Line C 3 mm 391 366 339 10 mm 389 373 391 20 mm 220 260 220 23 mm 153 156 143 a) b) c) d) Fig. 5 Typical microstructures observed in the various regions of the FTS welded plate: a) parent plate showing ferrite-pearlite; b) lower temperature heat-affected zone (HAZ) of fine-grained bainite; c) high temperature HAZ comprising coarse grained bainite; d) weld metal showing a bainitic structure with spheroidal carbides.

Within the framework of the two-phase grain model (by the example of γ-Fe203 cobalt coated particles) a theoretical analysis of the effect of uniaxial mechanical stresses on the magnetization of the system of hetero-phase interacting nanoparticle was held.
When H ≠ 0 transitions, for example, from the third state to the second or the fourth corresponds to one rotation of the magnetic moment of the phase transition in the first - total angular grains.
(7) Here ni=n1,⋯,n4 is the distribution density in the diagram {ε, q} of the number of particles in the i-th state, Ni0 is the number of particles in one of the four equilibrium states h=0.
Reference number is Government Order-2013/287, code 2.8649.2013.
Number 2, 1988, pp. 101-105; [3] Afremov, L.L., Panov, A.V.

An increase in the strain rate together with an increase in the number of passes does practically not change the type of the formed texture.
In the given case ECAP of W at 1000°C is one of the types of the deformation-thermal treatment, allowing to receive an average grain size less than 1 µm.
The given type of texture is not changing significantly when varying the number of passes and choosing different types of ECAP routes.
Apparently, this fact can be explained by a limited number of slip systems in HCP metals unlike in case of the materials with cubic crystal lattice.
The regularities of the texture evolution at HPT and ECAP by the example of pure Cu are accompanied by microstructure evolution from the coarse-grain state to the ultrafine-grain one.

The results of the core data analysis show that the Borehole 440 is dominated by fine-grained materials.
The ground at this drilling location is dominated by fine-grained materials.
At borehole 103, the percentages of fine-grained material and coarse-grained material are equal.
Borehole 202 is dominated by fine-grained materials.
The finer grain-size rock masses generally have a higher rock mass quality value.

Critical microstructural features include a phase fraction and morphology, prior-b grain size, grain and subgrain boundary morphology, and matrix characteristics [3].
Model Setup For practical forging applications, a comprehensive recrystallization model predicts the distribution of parameters such as: temperature after deformation heating and heat loss to dies; stress as a function of temperature, strain rate, and strain; and grain sizes after dynamic/static recrystallization and grain growth.
In the current work however, both initial grain size and strain were considered constant in the a+b regime.
An increase in equiaxed ap accelerated recrystallization kinetics due to an increase in grain boundaries associated with a refined initial grain size and the additional presence of a/b grain boundaries that were observed to be preferential nucleation sites over b/b grain boundaries [7].
The predictions from the finite element model had an average error value eavg=(i=2jei/j where number of data points and e=fsrx,predict-fsrx measureover all measurements of 0.09, which was marginally greater than the experimental error of 0.06.

H.Vogel model is shown as follow: (1) where， is the ordinal number of the sunflower kernels.is the phyllotaxis parameter.
The abrasive grain blocks are composed of hard polyurethane and abrasive grains.
A lot of abrasive grain blocks are ranged with different phyllotactic parameter m and the diameter D of abrasive grain block on bionic polishing pad surface, and the clockwise and counter-clockwise phyllotactic grooves between the abrasive grain blocks can be generated.
The printing ink is composed of polyurethane and SiO2 abrasive grain.
The height and diameter of its abrasive grain block is 0.2mm and Ø2.4mm, respectively.

Table 2 Welding parameters used for this study Specimen number Welding current I/[A] Welding speed v/[mm·s-1] 1 92 6.5 2 92 5 3 92 4 4 130 9.9 5 130 9.2 6 130 8.5 Results and discussion Fig. 1(a)-(f) show the microstructure of the weldments 1-6, reveal the size and shape of grains of the fusion zone(FZ), heat affected zone(HAZ) and base metal.
It has been known that the FSS weldments develop coarse grained zones influenced by the concentrated heat.
The different thermal capacity and different growth trends of the different grains result in inhomogeneous state after growing up.
In welding process, the grain growth direction is along the heat loss direction, the pool heat loss direction is perpendicular to the isothermal section, so the direction of grain growth is perpendicular to the isothermal section[10].
The grain growth direction perpendicular to the isothermal section, which makes the angle between columnar crystal growth direction and the weld center larger.

Thus, MA is a complex process and includes optimization of a number of ball milling parameters such as rotating speed to achieve the desired product [8].
It was obvious that a number of thin slice particles were formed due to the severe plastic deformation of the plastic particles such as Nb and Ti.
The peak broadening indicated the formation of fine grain and/or a large micro-strain in the powder particles.
Moreover, it was decided by XRD analysis that the average grain size decreased while the micro-strain was improved.
Sun, Preparation of fine-grained Mo-12Si-8.5B alloys with improved mechanical properties via a mechanical alloying process, J.