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During the SMAT process, the metal surface was shot-peened by a large number of stainless steel balls.
The microstructure is characterised by uniformly distributed equiaxed nanometer scale grains (grain size in the range of 50nm to 100nm).
At the depth of 80m, there existed a large number of submicrometer scale grains (up to 0.3m).
At a depth of 220m, apart from some submicrometer scale grains there were also a few large grains in the size of 1-2m.
The grain size ranged from 50nm to 100nm.

The α laths appear to be coarser at the interior of the grains and finer in regions adjacent to the grain boundaries.
In the LM image a dark phase can be seen formed along the β grain boundaries and as precipitates within the grains.
The distribution and number of precipitates within the grains is inconsistent.
However, there is significant contrast at the grain boundaries and so the grains in general are easily discerned.
The STA sample has a more uniform dispersion and greater numbers of the fine lath like α precipitates, which are the greatest contributors to strengthening.

The surface preparation steps can permeate the pores and conformal CdS growth can be seen on the grain surfaces.
Therefore, it is likely that the grain boundaries are inverted, and have therefore n-type conductivity.
This is expected to result in a Voc loss of some 200 mV as Voc scales as the logarithm of the number of recombination centers.
One can now compare dense, vacuum deposited CuInS2 to porous, large grains, electrodeposited CuInS2 and to nanoporous DSC.
CdS deposition can be observed on the grain boundaries.

For fine-grained soils he found this method accurate in fully saturated cases only.
The thermal conductivity of a soil can be calculated as a weighted combination of dry and saturated soils, where „Ke” weighting factor is the Kersten-number.
„λdry” representing the thermal conductivity of dry soils: (3) The number 2700 represents the average density of solid minerals (2700 kg/m3).
For coarse-grained soils, if Sr > 0,05: (5) For fine-grained soils, if Sr > 0,1: (6) Soils can be differentiated as coarse-grained and fine-grained soils based on [3], and if a certain soil contains at least 5 % smaller than 2 μm (0,002 mm) particles, the soil is considered as fine-grained.
Identification of grained soils occurs with the grain size distribution curve, where the mass percentage of each fraction is necessary.

Microstructures, grain size and phases were determined by TEM and X-ray diffractometry (XRD).
TiC has a face center cubic (FCC) lattice type with space group Fm3m and α-alumina has a trigonal lattice type with space group R3c, which corresponding to the JCPDF file number 32-1838 and 89-3072, respectively.
TiC grains were usually located at Al2O3 grain boundary and triple junctions.
It could be implied that TiC played an important role in pinning effect and inhibiting grain growth of alumina during HIP process [2].
Castro, Sinter-HIP of alpha-alumina powders with sub-micron grain sizes.

The initial average grain size of the material was found to be 50 µm.
After the first pass average grain size reduces to 6 µm and grains are randomly distributed and some are elongated.
After second pass (route Bc) grain size reduced further and lamellar grains of 2 µm spacing were observed.
The material compressed in x direction after 3rd pass of ECAP shows elongated grains with higher density of dislocations, both inside the grains as well as near the grain boundaries.
As depicted in the Fig.9a.with increasing number of passes stage IV hardening tends to become narrower.

As shown in Fig. 5: austenite dominates the microstructure of Co-base alloy surfacing layer, a large number of cell grain structure can be seen clearly from the microscopic morphology.
Under the effect of electromagnetic, grain of surfacing layer organization more refine than not applying to magnetic field, when magnetic field current is I=3A, the refinement of grain achieve to the best state, and distribute uniformly.
Grain is refined by electromagnetic mixing mainly through the three ways to increase the nucleation rate under the effect of the magnetic field [3]: 1) dendrite fragments of the tail of molten pool; 2) separation of semi-molten grain in molten pool edge; 3) heterogeneous nucleation particles.
So, the growth time of dendritic crystal grain along the maximum heat reverse direction is very short, thus the size of grain is reduced.
Cobalt-based surfacing layer is mainly composed of matrix Co, cobalt carbide CoCx and carbide hard phase Cr7C3; In addition, there are a small number of Fe3C.

Apart from that, SEM shows that more addition of Cu dopant increase the grain size.
Analyses of the ceramic microstructure and composition indicate that Al ions are distributed in grain boundaries, and that uniform boundaries indexed as NiAl2O4 surround the grains has been made.
Although there have been a number of investigations on the electrical, optical and structural properties of NiO electroceramic, no systematic study have been done on the Cu doped NiO electrical properties at varying deposition conditions.
The increasing of grain size would increase in density as well.
SEM observation shows that increasing of Cu dopant concentration enlarges the grain size.

Numbers of research are focused on functional properties of porous materials.
In case of fine powders predominated small pores below 5000 µm2, whereas, in the structure of sinters made of coarse-grained powder, large number of bigger pores can be observed.
When materials porosity increased, jump number of open pores, which lead to growing of metal surface contacting with electrolyte, hence the current raise.
Figure 7 - SEM images of pores morphology of 316L steel sinter with porosity of 47% made of coarse-grained powder after corrosion test; magn.: (a) 100x, (b) 350x.
In case of sinters made of coarse-grained powders, pores dimension allows a free liquid circulation and effective formation of oxide protecting film Fig. 7).

Such discontinuous yielding characteristics has also been observed in a large number of bcc materials [10].
This microstructure exhibits newly formed recrystallization grains with irregular grain boundaries.
At the critical strain, the migration of a large number of interfaces leads to flow softening.
On the other hand, for the material with high stacking fault energy (SFE), the grain growth (big angle grain boundaries migration) rate is slow, a steady-state stress-strain curves occurs.
Fig.4 (c) shows a typical microstructure which includes a number of the local slip bands, some of which cross the grain boundaries, indicating the flow instability occur in the form of adiabatic shear bands.