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Imaginary part of the pseudo-dielectric function of a µc-Si:H film deposited on a-Si:H by the layer-by-layer method and measured at increasing number of cycles.
On the contrary, if the hydrogen flux is too high, a fast crystallization will be obtained but this will result in reduced grain size because of competitive growth of the high number of nucleation sites.
The numbers in brackets indicate the values of the RF power and the partial pressure of silane.
Besides crystallinity, the quality of the grains is an important parameter for electronic applications.
PSil stands for large grains polysilicon and PSif for fine grain polysilicon.

The average grain size is 10μm and no abnormal large grain is seen.
When the strain level continue to increase, the number of small grain decrease and some large grain appear once again.
Abnormal grain growth [J].
Abnormal grain growth and grain boundary faceting in a model Ni-base superalloy [J].
Influence of the primary recrystallization texture on abnormal grain growth of goss grains in grain oriented electrical steel [J].

In general, the metals and alloys having FCC lattice structure possess sufficient number of independent slip systems that can be activated at room temperature and therefore can be extruded at room temperature.
The equi-axed grains are of the size ~ 100 um.
These elongated grains resemble the original grains in as-cast conditions in terms of their volumes.
Some of these regions however do recrystallize but grain growth is restricted and thus these regions form a distinct colony of fine grain size (< 5 µm).
A higher degree of deformation (higher extrusion ratio) significantly lowers the volume fraction of unrecrystallized grains and improves the grain coarsening in the recrystallized grains.

Mechanical milling can bring about grain refining and change of lattice parameters.
Cu grain sizes are characterized by the peak of the XRD points of the composite.
The peak 1 and 2 of Cu the grain size peak changing with milling time.
After a long time of ball milling, grain was introduced in serious grain distortion, high density defects and nanometer fine structure, grain at high distortion stored energy state and the sintering activity improved which facilitating sintering densification.
For the composites being milled the grain continued to be refined and grains boundaries increase.

Too little water fails to develop adequate strength and plasticity where sands and clays grains are combined together apart thus the permeability is very poor.
The development of bond strength between the grains depends upon on the hydration of clay.
So, the clay becomes soft, lose its bonding power and less stiff and the sand grains are held further apart thus decrease the strength [7].
As a result gas has difficulty to pass through grain particles.
This has helped to remove the gases present in it thorugh the sand grains.

Tungstendisilicide (WSi2) was formed at the tungsten/silicon interface as well as grain boundaries of the silicon.
The size and the area of the silicon melting and the viscosity of the SiO2 layer were strongly influenced by The EB energy, which determined the size and the number of the voids in the capping layer.
The eutectic statistically distributed at the primary silicon grain boundaries.
In addition, the WSi2/Si eutectic became coarser at the primary silicon grain boundaries and spread more widely.
The strong tendency of formation of tungstendisilicide at the primary grain boundaries would reduce the efficiency of the solar absorber.

The typical nugget stirred zone and TMAZ are surrounded by a heat affected zone (HAZ) thus resulting in a very fine and equiaxed grain structure in the weld nugget causing good elongation [6].
Though large number of investigations has been carried out on friction stir processing of aluminum alloys, the study on friction stir processing of magnesium alloys is limited.
They investigated that FSP leads to finer and more homogenized grain structure.
These elongated grains are transformed into significant grain refinement in the nugget region and it has been reported that because of dynamic recrystallization due to frictional heat between the shoulder and the workpiece, initial elongated grain structure are transformed into fine equiaxed grains.
A significant equiaxed grain refinement is obtained in the nugget region, due to which the friction stir processed AZ31B material can exhibit superplasticity characteristics.

These lamellar LPSO phases arranged in the same direction in the same crystal grain, and arranged in different directions in different grains.
At the same time, it can be found that the number of particle phases decreased significantly, indicating that precipitated phases reintegrated into the matrix with the increase of deformation temperature.
A mass of DRX grains were produced after 1 pass.
After 2 passes, the grain size was consistent with the 1 pass.
A large number of precipitated phases produced with the decrease of the deformation temperature, which can pin the grain boundaries, so that the fine DRXed grains maintained the stability of the grain size during thermal deformation process.

It has been shown that the grain size and segregation of Si, Cu and Mg atoms from the solid solution in the grain boundaries area are the main factors that enhance the alloy strength.
SPD techniques allow realizing a number of strengthening mechanisms.
As a result a structure with an average grain size of about 100 nm and mainly with high-angle grain boundaries (NS state) was fabricated.
Konrad, in: Ultrafine-Grain Metals, edited by J.
Armstrong, in: Ultrafine-Grain Metals, edited by J.

Alemdag et al. [1] observed that the higher strains and the number of passes used, the better the material properties became.
Temperature affected the grain growth while the strain affected the deformation and the dislocation of the grains, resulting in a reduction in the size of the grains.
At the initial stage of deformation, the grains were large, as the deformation took place the large grains were broken down into small-sized grains.
These cumulative strains caused grain refinement and redistribution of the grains, sub-grains and phases, altering the hardness [12].
When an original sample of AA 7075 was tested for hardness experimentally, its average Brinell Hardness Number (HBN) was found to be 153.43.