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Although epitaxial growth of AlN is achievable on carbon-face SiC substrates, the crystals might contain sub-grains slightly misoriented with respect to each other.
Symmetric 0002 reflection rocking curves provide the tilt angles of sub-grains with respect to surface normal, in addition to crystallinity.
However, for the sample-II and III, this peak shifts toward a higher wave number of 655 cm-1, indicating the reduction of misfit stress.

Number of studies conducted on commercial aluminum-based composite systems revealed a decrease in ductility with an increase in crack initiation (stress accumulation) sites such as the amount of reinforcement particulates [20,21].
It is possible to induce such fine grains due to an intensive plastic flow and recrystallization around the ceramics particles or rapid solidification of the molten aluminium cooled from ceramics particulate[22].
%TiB2/SiCp composite showing small equiaxed grains of Al that formed on the ceramic particle surface.

Results of Work Quantitative assessment of a contribution to the general deformation of ready details [6] shows that on 30% stages of the mechanical and strengthening processing bring in it and ~ 40% are connected with an initial condition of metal (chemical structure, a hardenability, the grain size, etc.) and semi-finished product manufacturing techniques (stamping, heat treatment, cleaning, etc.).
Features of metallurgy – the content of the basic chemical elements, constant and other impurity, the grain size, a structural state, impurity degree etc. participate in an indicator of a hardenability of steel.
The problem can be solved due to application of the endothermic atmosphere with the content of hydrogen ~ 40% instead of 20% or by ammonia additive in number of 0.5 – 0.6% to the endogas which is in the furnace.

In ceramics, pores form when the grain boundary diffusion during sintering process is insufficient. [18] To estimate their influence on the transparency, we assume that the pores are spheres with different sizes.
Np is the number of pores per volume, which can be obtained through SEM (scanning electron microscope) observation.
Wang, Sintering dense nanocrystalline ceramics without final-stage grain growth, Nature 404 (2000) 168-71

Polycrystalline or amorphous inorganic films deposited at a lower substrate temperature contain a large number of nonradiative recombination centers, so that these films can’t use as emitting layer in LEDs.
The grain size of ZnO crystals deposited at 125, 150, 175 and 200 °C are estimated to be 5.8, 6.7, 10.1 and 15.2 nm from the full-width at half maximum of ZnO (110) diffraction peaks, using Scherrer’s equation.
The grain size of ZnO crystals increases with a substrate temperature.

DSC - curves of the Ti50Ni25Cu25 alloy: а) initial RQ b) after HPT However, after this crystallization the structure is rather heterogeneous and it contains very coarse grains of the austenite phase [8].
TEM investigations revealed also that the annealing of the SPD processed amorphous Ti50Ni25Cu25 alloy at 450 °C leads to a formation of a rather homogeneous nanocrystalline structure [9] in contrast to the annealing of the non-deformed amorphous alloy, where a formation of micrometer-sized grains has been observed [8].
The increase in the number of nucleuses of crystallization, their uniform distribution leads to a formation of a more homogeneous nanocrystalline structure.

The precipitates were located along the grain boundary in the diffusion zone.
It is expected that the grain boundary is the major diffusion path for nitrogen diffusion.
But, the experimental results carried out at 550°C for 5 hours, shows decrease of the number of precipitates compared with the treatment of 500°C.

Compared with a number of ceramic reinforcements, TiB has advantages on thermochemical stability, mechanical properties and thermal expansion.
So, fine-grained matrix microstructure formed in the composite coatings.
The cooling rate of coatings increases with the increasing of scanning speed and the uniformly distributed TiB formed firstly accelerate nucleation, which beneficial to form equiaxed grains.

The solubility of gypsum is conversely proportional to the particle size, its solubility increases linearly with increasing mesh number [7].
The grain size distribution curves of gypseous soil is shown in Fig. 1.
The grain size distribution of the soil.

(0002) a no RUB (0002) b single surface RUB (0002) c reverse surface RUB Fig. 4 X-ray analysis of the two RUB routes (1010) (1011) (1011) (1011) (1010) (1010) Table 4 Result of 4 3 16(4 2 )L × orthogonal experiment Serial number Levels E（mm） A B C D E F G 1 1 1 1 1 1 1 1 2.98 2 1 2 2 2 1 2 2 5.80 3 1 3 3 3 2 1 2 5.00 4 1 4 4 4 2 2 1 5.17 5 2 1 2 3 2 2 1 3.40 6 2 2 1 4 2 1 2 4.80 7 2 3 4 1 1 2 2 5.83 8 2 4 3 2 1 1 1 5.46 9 3 1 3 4 1 2 2 3.80 10 3 2 4 3 1 1 1 5.90 11 3 3 1 2 2 2 1 5.70 12 3 4 2 1 2 1 2 5.47 13 4 1 4 2 2 1 2 3.43 14 4 2 3 1 2 2 1 5.03 15 4 3 2 3 1 1 1 6.20 16 4 4 1 4 1 2 2 5.40 Ⅰ 18.95 13.61 18.88 19.31 41.37 39.24 39.84 Ⅱ 19.49 21.53 21.1 20.39 38.00 40.13 39.53 Ⅲ 20.87 22.73 19.29 20.50 Ⅳ 20.06 21.50 20.33 19.17 R 1.11 9.12 2.22 1.33 3.37 0.89 0.31 Mechanical Property.
Before RUB, most grains were not activated because the basal planes were parallel to the axial direction of tensile stress and their Schmid factors were approximately zero due to the very strong basal texture, so the strength is high while formability is poor.
After RUB, grains rotated and (0002) basal texture component was weakened (Fig.3) which led to increase of the Schmid factor of basal-plane slip system which then was easy to start up[9].