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Transmission electron microscope (TEM), high resolution transmission electron microscopy (HRTEM) and energy dispersive spectrometry (EDS) were used to systematically analyze the morphology of precipitates and their grain orientation with matrix at different tempering temperatures.
Finally, steels are air cooled to room temperature after tempering at different temperatures varying from 450℃ to 600℃ for 2h ( the samples are marked by numbers 1# to 4#).
Coarsening of precipitates causes that the number of precipitates particles decreases and distance between precipitated particles increases.
Each ring of the polycrystalline ring represents a group of grain crystal planes.
The largest number of circular particles have smallest size and of approximately 10nm.

This alloy has been widely used as master alloy by the aluminum casting industry for grain refining wrought alloys.
This master alloy contains some large TiAl3 particles ranging between 10 to 50 µm and a large number of TiB2 particles smaller than 10 µm.
The inserts in Fig.3 show that a large number of small TiB2 particles exist in interdendritic areas.
Although a small number of large TiAl3 particles were indeed engulfed by dendrites, the engulfment, however, was due to the nucleation process, in which large TiAl3 particles served as nuclei of the aluminum grains/dendrites.
Conclusions Apart from a small number of large TiAl3 particles that serve as nuclei for the aluminum grains/dendrites, other TiAl3 particles and TiB2 particles are pushed or rejected by the growing dendrites and are segregated in regions between dendrites arms.

This heat treatment produces a dispersion of very fine grained precipitates in alloys.
If the material is heated to above the maximum solution temperature, the grain boundary melting may occur and the material failures.
Totally 27 number of experiments were conducted.
If full factorial experiments were conducted 243 number of experiments had to be done.
Degree of freedom is one minus the level number.

The results indicate that the nanostructured zirconia coatings with original nanostructure and columnar grains have higher microhardness and adhe- sive strength than the conventional counterparts.
Vertical microcracks are observed in the coating along the column grains as a result of the release of thermal stresses when splats solidified and cooled down quickly.
The columnar grains undergoing several splats in the nanostructured coating present a different morphology with that in the conventional coating.
Consequently, after finishing a lamella it contains columnar grains through the lamella.
It may be explained that there exist a number of process-related defects such as micropores, microcracks, intersplat gaps in the molten regions, which influence microhardness values significantly, reflect the data scattering obviously within the distribution.

The concrete conglomerate properties change over time and depend on a number of factors.
The grain composition also plays a very important role in the concrete resistance to external loads, since as its composition reaches the optimum, the contact area between the aggregate grains increases including the concrete durability and elasticity approach to similar properties of the aggregate.
The closer the aggregate grains are located to each other, the greater the stress is, the less the cement stone shrinkage strain is, and the more the likelihood of forming microcracks between adjacent grains is [9, 10].
At significant distances between the aggregate grains, the own cement stone shrinkage is manifested to a greater extent.
The ratio between the sand-cement mortar and contact layer rupture areas will depend on the aggregate grain size and composition.

Laser grain-size analysis (Model BT-9300H Laser granularity distributing apparatus and Model BT-600 deconcentrator) was carried out in China University of Geosciences, Beijing with the triethanolamine as dispersing agent.
The grains are partly embedded in the glassy phase and the internal grains generally are random.
In Fig. 3(A) and Fig. 3(B), a big dendritic particle which is consisted of multi-length fibroid grains intergrowth about 350 nm in size can be observed clearly.
From the calculation results of mullite crystal(JCPDS Card number is 15-776), d(001)= 0.289 nm, d(400)= 0.189 nm and d(401)= 0.158 nm, the angles between these planes are f(001)^(400)= 90°, f(001)^(401)= 33.19° and f(400)^(401)= 56.81°.
Moreover, the SAED pattern of mullite illustrates that the grains has a zone axis of [uvw]=[040].

The grain height and width of GaZnO thin films deposited at different temperatures.
Fig. 3 shows the grain height and width of GaZnO films deposited at 250, 400, and 550 oC, respectively, which were measured by AFM.
On the other hand, from the deposition temperature of 400 oC to 550 oC, the carrier concentration of the film decreased mainly because of the increased number of chemisorbed oxygen ions which plays as trap for electrons.
The measured mobility may be influenced both by grain boundary scattering and ionized impurity scattering.
For low substrate temperatures (TS~250 oC to 400 oC), the grain boundary scattering decreases as the number of grain and roughness increases, while the ionized impurity scattering decreses as carrier concentration decreases for the samples with high TS upto 550 oC.

Average grain size estimated from GIXRD using the Scherrer formula found to lie in the range of 48-55 nm.
Uniform grain distribution can be seen in the AFM and the average grain size estimated from the AFM images lies in the range of 40-45 nm.
Such a grain alignment is attributed to the sputtering and surface diffusion induced by ion irradiation.[12, 15].
This ordered rearrangement of grains may provide a current path by increasing the number of metallic filaments under the influence of electric field.
We therefore feel that the large area filament density, i.e., number of filaments per unit area (emerging as a consequence of ion beam induced defects) away from the metal/LSMO interface, may be responsible for the observed RS switching in Ag/LSMO/Ag planar structures.

To increase HDD capacity, current research interest is on reducing the grain size of the media, decreasing the head flying height, employing a femto slider, and increasing both the number of platters and of the head gimbal assemblies (HGAs).
The higher the disk rotational speed, the higher the number of particles generated.
The effect of Brownian motion is also ignored because of the high Peclet number of the particle [11].
Figure. 6 Number of particles trapped from various HGAs with circulating filter located at left position.
Figure. 7 Number of particles trapped from various HGAs with circulating filter located at right position.

On mechanical properties, Young's modulus and hardness values increase for layers number increase.
These surfaces revealed that the TiN/NbN multilayer coatings consisting of up to 64 alternating layers had much smaller grains and uniform dense.
The morphology of grains size is important for a great effect on mechanical properties and friction coefficient in the experimental process.
The number of layers increased resulting in decrease of the friction coefficient.
Summary The TiN/NbN multilayer films produced for different total number of layers of 4, 16, 32 and 64, and total coating thickness about 2µm.