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This method is called the templated grain growth (TGG) method.
Therefore, the origin of the splitting is related to the template grains since the increased intensity of these peaks is based primarily on the diffraction from the oriented grains [9].
This kind of grain boundary is called “flat” grain boundary [8].
Therefore, the flat grains contribute the evolution of grain oriented growth.
Increases in the number and size of grains with flat boundaries are directly related to an increase in the texture fraction.

Ensuring Strength of Fine Grained Concrete with Mixed Cement Binders A.
Yung it has been proven that hardened cement stone contains a large number of unreacted cement grains, which can be replaced without loss of strength with the corresponding fractions of mineral additives.
In modern construction, the use of fine-grained concrete (FGC) is due to its special properties compared to traditional heavy concrete.
Purpose of the Work Ensuring the strength of ordinary fine-grained concrete with the rational use of cement.
However, this indicator is equalized by the number of CASB with its maximum amount (х2=+1) in concrete 400 kg per 1m3.

Superplastic Sinter-forging of Fine-grained Si3N4-Si2N2O Composite at Low Temperature J.T.
SEM experiment conforms that the average grain size of sintered body is less than 300nm.
A number of researchers have demonstrated superplasticity in several silicon nitride ceramics by applying the transient liquid phase[3,4], using ultrafine β-phase powders[5,6], or by adding secondary phases into Si3N4 to refine the microstructure[7].
Alternatively, at constant stain-rate, the forming temperature can be decreased with smaller grain size.
Microstructures of as-hot-pressed materials are very fine and uniform, with average grain sizes about 300nm.

While desired applications of ceramics and their composites are mainly at high temperatures, very few numbers of investigations have been focused on high temperature mechanical properties and creep response of CNT-reinforced ceramics, so far[4-6].
Since grain boundary sliding has been accepted as the most important mechanism for high temperature ceramics plastic deformation, the grain boundaries nature has a vital role on the deformation behavior of polycrystalline ceramics [7].
Well-dispersed CNTs among the ultrafine 3Y-TZP grains with size of about 100 nm are observed.
(1) where G is the shear modulus and d the grain size.
In the model, Kjun represents the restoring force due to the elasticity of the adjacent grains, and the dashpot of viscosity h represents the amorphous layer between the grains.

Thus, whereas conventional treatments may refine the grains to sizes of several micrometers, SPD processing is capable of producing grains having sizes within the submicrometer and nanometer ranges.
The grains produced in SPD processing are designated ultrafine grains (UFG) where UFG solids are defined specifically as “bulk solids having fairly homogeneous equiaxed microstructures with average grain sizes less than ~1 mm and with a majority of boundaries having high angles of misorientation.”
Within the range of UFG materials, submicrometer grain sizes refer to average grain sizes within the range from 100 to 1000 nm and nanometer grain sizes refer to average grain sizes of less than 100 nm.
This work provided a clear demonstration of the ability to achieve remarkable grain refinement in commercial metallic alloys with, as an early example, a reported grain size of ~0.3 mm in an Al-4% Cu-0.5% Zr alloy [9] at a time when the minimum attainable grain size in a comparable western alloy was of the order of ~3-5 mm [10].
These numbers reflect the considerable interest in ECAP around the world and the relatively small number of active HPT facilities.

However, at an elevated temperature, grain growth may occur.
Comparison of surface roughness, grain height and grain diameter of titanium vanadium nitride coatings prior to and after heat treatments.
AFM measurements showed that grain refinement had occurred in the coatings, but a mixture of grain sizes from 90 nm to 200 nm existed in the samples after heat treatment.
The value of ko was considered as the limiting grain size for grain refinement under specified deposition conditions.
It should also be noted under different nitrogen deposition pressures, the number and the energies of the depositing species approaching the substrate may vary, therefore the grain structure and its associated properties may change in the coatings deposited at different nitrogen pressures, which may lead to different annealing behaviour in subsequent heat treatment process.

This coarse-graining model using sub-divided region with high order interpolation function is adopted for finding the positions of atoms and for describing deformation on the curved structure.
Coarse-grained energy and equilibrium equation in system We regard the group of atoms around a specific node as the cluster.
The coarse-grained model has a total number of degrees of freedom 30360 (including inner displacement 1560), while MM model has 72000.
Fully atomistic simulation needs a total number of degree of freedom 12120 but our model has 8931 (including inner displacement 723).
We note that though inner displacement in coarse-graining model for CNTs occupies very small the number of degree of freedoms, it has a great effect on the deformation and on the strain energy curve (See Fig. 1(a) and Fig. 2(a)).

Results In the as-received condition, α-Ti showed equiaxed grains mixed with elongated grains as in Fig. 1(a).
The number density of recrystallized grains, as shown in Fig. 5(b), increased with the temperature of the preceding rolling.
From the comparison of the number density of recrystallized grains in as-recrystallized state, i.e., 1600 min. at 600°C it is surmised that the average size of recrystallized grains decreased with the increase in the rolling temperature.
(a) Recrystallization kinetics at 600°C of CP-Ti rolled 60% at various temperatures between 25°C and 600°C, and (b) variation in the number density of recrystallized grains with annealing time at 600°C.
Beside, the increase in the number density of recrystallized grains in the warm-rolled specimens, Fig 5(b), suggests that the microstructural heterogeneity introduced by diverse slip systems yielded additional nucleation sites.

Acetic picral solution was used for grain boundary etching.
The grains are not completely recrystallized and a high amount of low angle grain boundaries was detected.
With increasing number of ARB passes, the grain size decreases no more (see Fig. 4).
With increasing number of ARB passes, the intensity of basal texture rises.
Compressive yield strength (YS) and the maximum strength (σmax) dependence on number of ARB passes.

Novelty of this technique is one can build up significant amount of plastic strain by increasing the number of passes without much dimensional change.
Hence, the mechanical properties of Al-Li alloys are primarily dependent on grain size, nature, volume fraction and distribution of precipitates, both within the grains and at the grain boundaries and occurrence of precipitate free zones (PFZ).
Usually, a single grain is found to nucleate at any particle at the maximum.
These recrystallised grains were estimated to be in the size range from 20nm to about 100 nm.
It is suggested that with the assistance of non-deformable particles, it might be possible to get ultra- fine/nano-crystalline material through ECAE with relatively lesser number of passes.