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The ball milling of aluminum powder leads to an increase in specific surface area, a decrease in apparent density and a decrease in the value of the crystallite size, which indicates a decrease in grain size.
The studies performed allowed proposing various technical inventions to enhance the choice of the working gas and its parameters (pressure, temperature), the proper shapes and sizes of powder particles, the spraying strategy (nozzle traverse speed, number of passes, pre-heating of powder, spraying angle, etc.), and the arrangement of sublayers (to enhance coating adhesion) and masks (to produce patterned coatings).
Ball milled particles are characterized by a layered structure consisting of a large number of ultrafine aluminum particles.
It can be seen that the ball milling of aluminum powder leads to the following changes: the specific surface increases from 0.26 to 0.42 m2/g, the apparent density decreases from 1184 kg/m3 to 1156 kg/m3 for a ball milled material, the mean particle size of the powders increases from 29.38 to 34.52 μm and the value of the crystallite size decreases from 60 to 49.48 nm, which indicates a decrease in grain size.
The ball milling of aluminum powder leads to the following changes: the specific surface increases from 0.26 to 0.42 m2/g, the apparent density decreases from 1184 kg/m3 to 1156 kg/m3 for a ball milled machined material, the mean particle size of the powders increases from 29.38 to 34.52 μm and the value of the crystallite size decreases from 60 to 49.48 nm, which indicates a decrease in grain size.

SnS2 can exist in a number of polytypes [9].
This suggests that lattice strain in thin films restricts the growth of grains.
The number and diameter of bumps decrease when the substrate temperature increases.
This change in optical energy gap can be explained by the increase in grain size [16].
When the temperature increases, it causes a significant augmentation in the grain size of SnS2 thin films.

It is known that increasing the finishing temperature leads to more uniform and fine-grained structure.
Effect of Number of Rolling Pass.
To find out about the relationship between the number of rolling passes and the surface roughness, the values of surface roughness (Ra) have been plotted against the number of rolling passes as shown in Fig. 4.
It can be seen that with increasing the number of rolling passes the surface roughness is reduced.
The suggested explanation is that the increase of the number of rolling passes means increase of the reduction.

As compared to the non-doped one (Fig. 3 S1), the average grain size appears smaller in the 2 at% N-doped sample (Fig. 3 S2).
When the nitrogen content increased to 4 at% (Fig. 3 S3), the thin film surface became non-uniform and the grain size became greater.
However, when the substrate temperature was further increased, the grains grow up and surface roughness increases with reunion phenomenon (Fig. 3 S4-S6).
The number of adherent platelets on the surface of nitrogen-doped TiO2 films is obviously less than that of pyrolytic carbon films.
Adhered platelet number and decrement rate of platelets for blood platelet on TiO2 and untreated pyrolytic carbon films, respectively.

According to modern views [12, 18, 20, 21, 22] the process of interaction of calcium carbonate with the products of hydration occurs on the surface of calcite grains.
As a result, the surface of calcite grains may contain compounds of the type: calcium hydrocarbonylates (3CaO×Al2O3×CaСO3×10H2O; 3СаО×Al2O3×nCaCO3×mCa(OH)2); calcium carboferites (3СаО×Fe2О3×СаСО3; 3СаО×Fe2О3×nСаСО3×mCa(OH)2; double compound Ca(OH)2×СаСО3.
The number of newgrowths in the cement stone is increased by the amount corresponding to the amount of calcium carbonate bound [20].
Frost resistance studies have shown that the concrete grade by frost is considered to be secured due to the required number of freezing and thawing cycles, Кfrost res≥0,95.
Sample number % chalk by total weight of cement and chalk Number of freeze and thaw cycles 45 75 110 150 № 1 0 1,21 1,18 1,0 0,75 № 2 10 1,28 1,26 1,15 0,95 № 3 20 1,25 1,21 1,1 0,8 № 4 30 1,15 1,11 0,89 – № 5 40 1,11 1,04 0,82 – Кfrost res≥0,95 Fig. 3 Frost resistance coefficients of concrete samples.

Introduction In the mine building project, we need to make use of a large number of steel in the construction of concrete and the production of precast concrete components.
Table 1 is the situation of inclusions and grain size of cold--rolled thread steel and cold-drawn smooth steel.
From the table, we can see that the grain size of steel is very small, the differences of inclusions are also small, either cold-rolled process or cold -drawn process.
Table 1 The metallographic organize of the cold-roll thread steel and smooth steel Categories Specifications Inclusions Grain [Φ/mm] [size] Cold-rolled thread steel 5.5 Small sulfide 9 Cold-rolled thread steel Cold-drawn smooth steel 6.0 5.5 Small sulfide Small sulfide 9 9-10 Mechanical Properties.
The experiment is composed of five groups, the number of specimen for each group is 10, and the results are shown in table 4.

By metallographic analysis and performance tests, the results show that microstructures are compact, grains are fine and mechanical properties are excellent.
The number of pores in billets gradually decreases; the interfaces wettability and binding ability are improved by mass transferring.
The grains are finer.

The results are discussed on the basis of Schmid factor analyses in conjunction with microstructural features namely, grain morphology and precipitation.
In general, variations of properties with the positions and directions are caused by crystallographic texture, morphological features (such as shape and size of strengthening precipitates, grain morphology, extent of recrystallization), compositional inhomogeneity, and variations in quenching path [1-3].
This is due to the fact that the matrix contains high number density of shearable precipitates (h¢) and the solid solution is depleted of solute elements.

The results show that the multilayer coatings were smooth, dense, and small in grain size with clear layered structure.
Compared with traditional electroplating, brush plating often provide coatings with more condense structures and finer grains.
Table 1 Samples prepared for corrosion tests samples Ni Pb Pb/Ni 1# Pb/Ni 2# Number of sublayers 1 1 5 for each 5 for each Top layer Ni Pb Ni Pb Characterization and Corrosion Tests.

Using the measured orientations of adjacent martensitic variants, the orientations of parent austenite grains were calculated under the assumed orientation relationships for the austenite to martensite transformation.
Based upon the correct identification of individual orientations, the microstructural and crystallographic characteristics concerning the number and the shape of martensitic variants, the inter-variant orientation relationships (ORs), the twin interfaces and the martensitic transformation ORs were revealed with statistical reliability and reproducibility.
It is seen that the martensitic plates are self-accommodated and clustered in colonies, where one colony or several colonies are located within one original austenite grain.
If the different sets of austenite orientations predicted from all individual martensitic variants within the same initial austenite share a common orientation, the assumed OR should be the one that governs the martensitic transformation, and the resultant common orientation is the orientation of the initial austenite grain.
Let be the orientation of an austenite grain with respect to the orthonormal sample coordinate system.