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Granular films with well isolated grains can be obtained only with small film thickness (around 6 nm), when the grains are mostly spherically shaped.
To obtain the desired microstructure of well-isolated columnar grains, with a size less than 7 nm, a high C content is needed to form continuous grain boundaries at the initial film growth stage.
Thus, the grain size can be preserved due to the presence of the rigid grain boundaries, and the epitaxial growth of grains is ensured, to form grains with high grain aspect ratio.
For example, to obtain a recording density of about 4 Tb/in2, each recording bit must occupy an area of 160 nm2; or, with an average grain size in recording layer of 4.5 nm, an average grain pitch of 5.4 nm and at least two grains in the track direction, it results a track pitch of maximum 15 nm [15].
Acknowledgements This work was supported by a grant of the Romanian National Authority for Scientific Research, CNDI– UEFISCDI, project number PN-II-PT-PCCA-2011-3.2-0373.

The raw materials grain composition optimal distribution method in the representative volume of the composite is currently widely used to regulate the technological properties of ceramics using ash and slag waste.
Optimum granulometry allows to increase the mineral grains packing density, to reduce the elastic expansion of the compact after relieving pressure and to eliminate the repressive cracks formation.
However, the insufficient raw materials grain composition optimal distribution method knowledge, affecting the basic physical and mechanical characteristics of ceramics, determines the need to develop a new experimental method of mathematical composition of the ceramic compositions of the «loam + ASW» ceramic masses.
The pre-burning properties of clay raw materials had been previously studied, characterized by the following indicators: plasticity number - 16,46%, molding moisture - 31,59%, air shrinkage - 5,2%, coefficient of sensitivity to drying - 0,78.
Since loams contain a large number of quartz inclusions with a melting point of 1450 ° C, an additional silicate-lump of melt is introduced in the amount of 10 % by mass, to form a sufficient number of melted eutectics and to destroy the quartz crystal lattice.

The SEM displays that the as-deposited film is composed of uniformly distributed grains and the surface seems dense.
After heat treatment under 200°C for 30 minutes, the grains become a bit larger.
After heat treatment under technique 2, little change of the size of grains is presented in Fig. 2, implying that low heat treatment temperature under 85°C would not change the distribution and size of grains.
Table 1 Surface micro-hardness data of TiN 4 # film measured by nano-indenter Point Number 1 2 3 4 5 6 7 8 Hardness (Gpa) 19.25 25.25 27.03 23.35 19.12 17.88 26.04 27.56 Point Number 9 10 11 12 13 14 15 Hardness (Gpa) 25.58 19.66 20.05 26.33 24.77 32.74 22.41 Fig. 4 shows the surface morphologies of TiN 5# film before and after corrosion experiment in SBF.
Acknowledgements This work was financially supported by Shanghai Fundamental Key Project under contract number 08JC1421600 and Jiaxing Engineering Technology Centre of Light Alloy Metals, Chinese Academy of Sciences.

Introduction Today, an increase in the strength and plasticity of metals and alloys by grinding grains, fragments (or subgrains), and substructure cells is widely used.
According to the published data, the weld zone and the heat-affected zone in titanium alloys have a different number of characteristic sections that reflect different limiting heating temperatures and different cooling rates [9].
At the second stage, the metastable phase b-Ti can breakdown into a number of metastable phases w-Ti, α¢¢-Ti and α2-Ti [8, 11].
Numbers indicate the places of indenter “pricks” in different structural components of the alloy: 1 is in a single-phase grain with a low microhardness value; 2 is in the structure region with high microhardness values; 3 is at the interface boundary Such a spread of microhardness values is caused by the circumstance that the indenter, when pricked on the surface of the sample, falls each time either into different phases or into interfacial boundaries.
Sharkeev Yu P 2010 Evolution of the structure and mechanical properties of ultrafine-grained titanium Mat.

Introduction Magnesium and its alloys have excellent physical and mechanical properties for a number of applications.
Rapid abrasive tests were carried out by using wear and friction test apparatus with applied load of 50N and number of rotation of 200r/min.
As it is revealed, the size of grain clusters increased significantly with the increase of current density.
This can be ascribed that increase of current density will promote the nucleation of new grains and the growth of nucleated grains, thus the coatings with rough macro surface.
As it is indicated, incorporation of nanosized SiC particles did not make the position of Ni peaks shift, but Ni peaks broadened noticeably, which reveals the introduction of SiC particles could refine the grain size of Ni matrix.

Due to their peculiar structure, large number of layers and thickness in the nanometer range, coatings with submicrocrystalline structure and nanostructured coatings combine the qualities of layered systems and the specific properties of nano-objects.
Carrying out the process under conditions of ionic bombardment intensifies the processes observed during the deposition of multilayer coatings contributes to a fine-grained structure, nanoscale grains and layers, as well as the formation of complex compounds by (Fig. 1): - the kinetic energy of the bombarding ions which is supplied to the coating and is converted into heat for the local structures; - the possibility of cleaning the surface for a coating deposition; - the increase the number of active adsorption centers and the density of centers of nucleation; - activation of plasma-chemical reactions of synthesis of complex compounds by supplying heat directly into the zone of the formation and growth of atoms; - the increasing the degree of ionization of the condensed stream to reducing the temperature of synthesis of coating and to curbing the growth of grain sizes, as well as to amorphization of the growing film; - the stimulation of the diffusion processes at the interface between
For the formation of a fine-grained structure, effect of the additional ion bombardment is the most essential.
In the cavity formed by the parts surface and the screen, the generation of charged particles by oscillating electrons, the number of ions bombarding the surface and the speed of its spraying increase.

The experimental data have allowed to (temperature and grain size) on the speed of liquid metal front Mg7-FeSi alloy.
from the weight of the melt filled in the casting mo is explained by the fact that a number of Ukrainian companies use initial iron melt with a high sulfur content (0.030-0.035 %) in ductile iron production technologies.
High Mg7-FeSi alloy consumption that a number of Ukrainian companies use initial iron melt with a high 035 %) in ductile iron production technologies.
Phase-to-phase interaction can proceed and under the combined scheme when the part of master alloy grains is dissolved in a reactionary dissolved in the conditions of moving liquid inetics into the Granular Mg Master Alloy.
It is shown that depending on process param can be impenetrable, partially penetrable and completely -to-phase interaction character can be accordingly superficial, phase interaction can proceed and under the combined scheme when the alloy grains is dissolved in a reactionary layer and the part of grains emerges and is dissolved in the conditions of moving liquid-solid environment.

The addition of Mn3N was found to contribute to α-Fe grain refinement to a certain extent, but to harm the uniform growth of the τ1 phase in the stage of subsequent annealing. 1.
Table 1: Microalloying elements and their effects on the α-Fe grain refinement of solidification microstructure.
To evaluate the size scale of each solidification microstructure, the average radius ratios, rave/rave0, where rave0 and rave indicate the average radii of the α-Fe dendrite particles of the primary crystals in the alloys without and with a microalloying element, respectively, were estimated by the following equation: n0/n = (rave/rave0)3, 　 (2) where n0 and n are the numbers of α-Fe particles per 0.01 mm2 in the solidification microstructures in the alloys without and with a microalloying element, respectively, cut perpendicular to the solidification direction.
However, nitrogen is expected to be segregated at the α-Fe/FeLaSi phase boundaries, since it is known as one of the grain boundary segregation elements in pure α-Fe [20].
The addition of Mn3N was found to contribute to α-Fe grain refinement but to harm the uniform growth of the τ1 phase in the stage of subsequent annealing.

The grain images of 3(C) and (D) were completely similar to those of 3(B) in grain structural arrangement, but found to be slightly dense and compact with slight holes and a few nano-grain clusters.
The homogeneous grain arrangement eradicates intrinsic point defects observed in pure CZTS films.
The equation below occurs at the maximum intensity, n = 1, 2, 3,…., which is the number of planes, where λ from the equation is the wavelength of the beam.
The good bandgap range could be attributed to CTAB, which improved the grain size and compact crystalline structure [27,29].
[22] N Bakr “Deposition and Characterization of Cu2ZnSnS4 Thin Films for Solar Cell Applications,” International Journal of Applied Engineering Research ISSN 0973-4562 Volume 13, Number 6 (2018) pp. 3379-3388, Research India Publications, http://www.ripublication.com

The Al-Ti-C master alloy is considered to be a grain refiner which has good application prospects and is given detailed studies[3-4].The preparation process of Al-Ti-C master alloy, relationship between its microstructure and refinement effect have been studied[5-6].There are few reports in respect of researches on the precipitation phenomenon of second-phase particles TiC and TiAl3.
After the master alloys are added into the aluminum melt, fully stir to make them melt and mix well, thus getting the three groups of refined sample mass whose numbers are 1 to 3 successively and whose compositions are as listed in Table 1.
Fig.1 shows the XRD diffraction spectrum and microstructure photo of Al-TiC master alloy, from which we can see that in the master alloy only the TiC phase is contained, a large number of TiC particle groups congregate, and the particle size is between 0.1μm and 0.5μm.
It can be seen that the master alloy only contains the TiAl3 phase, which is block-like and in uniform distribution and large numbers.
When TiC and TiAl3 coexist in the aluminum melt, after 60 minutes of heat preservation, the differences in grain sizes on the top and at the bottom of the sample will decrease (Fig.6 (b)).