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Doping with La+3 causes reduction in grain size, whereas Sc+3 increase the grain size.
Also, it is found reduction in the grain size after doping.
As a result develops the relaxor actions in a number of perovskites such as Pb0.78Ba0.22Sc0.5Ta0.5O3 [26] and PbSc0.5Nb(1−x)/2Tax/2O3 (PSNT) with 0 ≤ x ≤ 1 [27].
Langman et al. [30] ascribed this grain size decrease to the solid solution impurity drag mechanism, which says that the presence of the La3+ ion concentration gradient at grain boundaries causes hindering of grain boundary mobility and subsequently leads to slow grain growth.
It shows a big reduction in grain size.

EBSD analysis of the ferrite grain.
LABGs are mostly observed to be distributed in the lath and/or in the pocket grains.
The PG grains became more equiaxed, and lath within it became more equiaxed.
Investigation of the Laves phase is firstly characterized by the SEM/BSE, because it has a high concentration of high atomic number of W, which appeared as bright in the micrograph (Fig. 3d).
The increase of creep stress accelerates the grain recovery during creep test.

For comparison, the grain size of the Ni-3Cr-10Al alloy was ~500mm, through OM observation, as shown in Fig. 2b.
During oxidation, metal elements diffuse along grain boundaries much more easily than through the lattice, for instance, the activation energy of grain boundary diffusion was approximately one-half the value for that of lattice diffusion in nickel oxide [20].
Therefore, the grain boundaries are much higher compared with the corresponding conventional Ni-3Cr-10Al alloy (average grain size is about 500 mm).
On the other hand, a great number of grain boundaries can also be regarded as the short-circuit path for Cr and Al diffusion outforward to the oxidation front [12-17].
Because the dispersed Cr and Al nanoparticles and a great number of grain boundaries promote the rapid selective oxidation for Al after oxidation as soon as possible, and after a continuous fine-grained oxide formation, Al diffusion along grain boundaries control the transport process.

Meanwhile, it can be seen that a number of newly refined grains are observed, indicating that dynamic recrystallization (DRX) occurs in evidence during hot compression deformation.
Compared with deformation microstructure at deformation temperature of 800°C, which the formation of new recrystallized grains was seen to occur in the interior of original grains and along the original grains boundary, the recrystallized grains of 750°C were developed only along some initial grain boundaries and no new grains were observed inside the original grains under optical microscope (Fig. 2b).
Recrystallized grains Elongated thin grains b Compression direction a Grain growth d Elongated thin grains Recrystallized grains c Fig.2 Optical microstructures of the solution-treated alloy (a), and the hot-compressed samples with temperatures of (b) 750°C, (c) 800°C, and (d) 850°C.
Meanwhile, the dynamic recrystallization process generates a number of nuclei, which originate at the old grain boundaries, with various orientations.
In the present study, as seen from the microstructure development in different deformation temperature, the microstructure are consisted of elongate and flat grains which show the DR features and DRX grains originated at the boundaries of deformation grains in case of 750°C deformation temperature, and deformation grains and DRX grains in the interior of original grains and along the original grains boundary in case of 800°C, and deformation grains and DRX grain growth in case of 850°C.

The effect of precursor type and hydrothermal crystallization conditions on the morphology of lanthanide manganese grains was investigated.
In a sintered form, a number of perovskites is suitable in high temperature environments.
As can be seen from Fig.3, the shapes and the sizes of LaMnO3 grains are distinctly dependent on the synthetic methods and treated temperature.
As the results shown in Fig.2, the calcine temperature affects dramatically the shape and size of LaMnO3 grains obtained.
Conclusion This study demonstrated that the temperature and hydrothermal crystallization strongly affect the sizes and their morphologies of grains.

The grain size affects the amount of oil carried during operation.
The final customer specifies the coating thickness, grain size, and grain quantity on the piston surface.
The grains are evenly distributed on the surface, without any gaps.
The grains are evenly distributed across the surface without any gaps.
Additionally, the difference is visible in the number of elements detected on the piston surface.

Electron beam energy density was 40 J/cm2, pulse duration 200 ms, number of pulses 200.
а – composite grain size D = 50…63 mm, E=40 J/cm2, τ=200 ms, N=50.
Scale bar in the images equals to 1 mm; b – composite grain size D = 80…100 mm, E=40 J/сm2, τ=200 ms, N=200.
The nanosize carbides are uniformly distributed inside the grains (Fig. 3 a).
On increasing the beam energy density up to 50 J/cm2 and keeping the other parameters constant, the grain size grows and carbide dendrite framework is formed inside some grains (Fig. 3,b).

Introduction The increasing demand of electrical energy in Europe and the world can be met by a number of strategies; one of them is to increase the efficiency of coal-fired thermal power plants.
The M23C6 are presented as M23C6 at grain boundaries (M23C6gb) and inside grains (M23C6gi).
GB: grain boundary; GI: grain interior 4.
Precipitates radii are available for grain boundary (GB), grain interior (GI) and γ′ precipitates.
References [1] Information on http://www.innovations-report.de [2] Special Metals Corporation, Nimonic alloy 263, Publication number SMC-054, 2004 (Sept 04) [3] W.Z.

Sintered compacts showed a highly densified compacts (∼95% relative density) while retaining fine grains in the matrix.
There are number of advantages in using TiC as the reinforcement for Cu based composites.
TiC distributes uniformly in the copper matrix so TiC particle acts as a grain growth inhibitor during sintering process.
The hardness enhancement is attributed to the grain growth restriction by pinning of TiC at the grain boundary.
Acknowledgements This research is funded by Vietnam National Foundation for Science and Technology Development (NAFOSTED) under grant number 103.02-2011.49.

A notable grain refinement of the alloys without altering the phase structures of the alloys obtained by melt spinning.
Fig. 3 presents the relationship between cycle number and the discharge capacities of the alloys at 100 mA/g current density.
Evolution of the discharge capacity of the as-cast and spun alloys with the cycle number: (a) Pr0.2; (b) As-spun (10 m/s) It is generally known that the discharge capacity of an alloy electrode is determined by compound factors, such as crystal structure, phase composition and micro appearance, grain size, composition homogeneity and surface state, etc.
The refinement of the grain is favourable to the discharge capacity because the grain boundary can accommodate the maximum hydrogen concentrations, whereas the increase of the LaNi5 phase is deleterious to the discharge capacity in virtue of its electrochemical hydrogen storage property being much lower than that of the (La, Mg)2Ni7 phase.
The melt spinning and Pr replacement give rise to a notable grain refinement instead of changing the structure of the alloys.