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In the view of a number of researches [2-5] one of the promising methods of intensive plastic deformation for mass production of ultramicrograin structures in strip and band are processes of vertical asymmetric sheet rolling based on asymmetry purposefully created by means of different speeds of working rolls, divergence of diameters and contact friction conditions, etc.
Mechanical properties and microstructures of ultrafine-grained pure aluminum by asymmetric rolling // Scripta Materialia. 2009.
Texture Control and Grain Refinement of AA1050 Al Alloy Sheets by Asymmetric Rolling // International Journal of Mechanical Sciences. 2008.
Shear deformation and grain refinement in pure Al by asymmetric rolling // Trans.

Hf-rich precipitates segregate close to the coating surface, along grain boundaries and at the interface between the additive layer and the inter-diffusion layer.
Mass change, mg/cm2 Number of oxidation cycle Fig. 1.
Inclusions of HfO2 oxide are formed on the grain boundaries of NiAl/Al2O3 phases.
Grain boundaries of Al2O3 oxide are the places of HfO2 precipitation.

The micrograph of Figure 2a differs from the 1a by having a greater number of pores, it´s attributed to a greater amount of quartz in the composition B, on the basis of the transformation of quartz (α) to quartz (β) during cooling, causing stress and cracks on the grain and the matrix.
Comparing of Figure 2c with 1c, there is, in principle, a disparity in the micrographs presented, because only perceives the emergence of mullite (primary or secondary) in the composition, which was not expected because according to Janssen [6], the microstructure of porcelain siliceous consists mainly of quartz grains, crystals of mullite, glass phase and pores or air inclusions.
The size and shape of grains and pores, as well as the composition and amount of vitreous phase are significantly affected by variations in the composition of the raw materials and the manufacturing process, but should be kept within narrow limits by technical standards (International Electrotechnical Commission, 1996).

.% of submicronic fraction of the same powder grade with an average grain size of 5-7 μm) by the SPS method at a compaction pressure of 30 MPa and temperature of 20500C.
The treatment of the film/substrate system by an electron beam was carried out with the SOLO (IHCE, SB RAS): energy of the accelerated electrons was 16 keV, energy density of the electron beam made 17 J/cm2, time between pulses made 0.3 s-1, number of pulses was 3, pulse duration made 200 ms, residual atmosphere pressure (argon) in the working chamber »2*10-2Pa.
The titan atoms penetrate into the volume of the ceramics through the grain boundaries dividing В4С crystallites.
The titan atoms penetrate into the volume of the ceramics through the grain boundaries dividing В4С crystallites.

A number of 6 specimens has been sampled [5], and from each specimen it was put together samples formed by 3 specimen tests for base material and 3 specimens for test welded head to head (Fig. 2).
In lack of an inclusion to decelerate the phenomenon of development of grains in the superheated area, the micro-structure in HAZ (Heat Affected Zone) and the seam will be formed from rough grains, with a low mechanical resistance and with characteristics of high plasticity.
As the crystalline grains are refined, they become more smooth, and the resistance characteristics increase[8].

It was observed that there was an increased on the atomic percentage of Sm as loading increases due to the number of Sm ions present in the electrolytic bath.
At 0.5% loading of samarium, it can be observed the formation of uniform grain size particles which are deposited onto the surface of nanosheets.
The uniform grain size of the Sm particles as well as the porous nature of cobalt nanosheets can be beneficial for ion transportation on the electrolyte for the application as an electrode for supercapacitors.
The formation of uniform grain size particles onto the surface of nanosheets as observed with 0.5% Sm can be favorable for the application as an electrode for supercapacitor due to the additional active sites for ions to interact.

The novel sediment sampler in this paper differs from the conventional hydrocyclone, of which its sediment outlet is sealed in the sediment collecting tank and the separation cone has been treated by different incisions according to the grain-size distribution of particles (Fig.1).
The laboratory simulation experiments were conducted to determine the separation efficiency for different grain-size particles.
(4) Where represents turbulent stochastic coefficient; represents average velocity; represents Gauss random number.
Assuming that the mass flow of sediment in the sampler is 100%, the separation efficiency for the particles with the grain size of 50~100 µ m has been determined to be as high as 78%~99%.

The small pores can be caused by the combustion of the organic substance used as a pore-forming agent, and the large pores may result from the accumulation of particles with a large grain size range.
Herein, the shape of the ZnO clusters was irregular, and the number of ZnO grains was reduced because of the less porous substrates.
Therefore, the number of adsorbed dye molecules is degraded and the photocatalytic activity is enhanced because the placement of catalysts in the porous material enhances the adsorption capacity [47].
Nikazar, technology, An investigation into the simultaneous influence of withdrawal speed and number of coated layers on photocatalytic activity of ZnO thin films, J.
Chen, Technology, Method for determining crystal grain size by x‐ray diffraction, Cryst.

Although the chemical stability of polycrystalline TiN which has been used in Al metallization is superior, it has been reported that Cu diffuses through the grain boundary of TiN to the Si substrate and results in barrier failure [3].
On the other hand, amorphous thin films are an attractive alternative to polycrystalline thin films because of the absence of grain boundary for diffusion, since most barrier failures occur along grain boundaries.
The Cu nucleation density represents the number of Cu particles per unit area in SEM micrographs.

The soldering parameters (temperature gradients, time above liquidus, etc.) determine the amount and the microstructure of these phases, such as the average grain size of the solder which has great influence on the mechanical properties of the joint.
Although it is very difficult to determine the number of tin crystallites in these cavities, the average size of these cells are characteristic as well.
The CO2 laser soldered samples has finer microstructure and smaller grain size (left).
Since the basic mechanical properties of the solder joints is determined by the average grain size of the solidified solder, the fine IMC microstructure has a key role as well.