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The impact of second phase grains on recrystallization hardness of Al-Cu and Al-Mn single crystals has been studied after the rolling process [5].
Average ultrafine grains have increased and it has been observed that orientation rate declined as the pressing temperature rose [7].
Temperature variations in the case of hot rolling (300 °C) process, as dependent on number of roll passes and time Fig. 6. 
Temperature variations in the case of hot rolling (400 °C) process, as dependent on number of roll passes and time Fig. 7. 
This temperature value has led us to the conclusion that the temperature would increase if the number of roll passes got higher.

In the laminated couples sintered by GPS, a significant reaction zone (~100-150 µm), containing a high aspect ratio of elongated polytypoid grains, was observed at the interface.
However, in the case of laminated couples sintered by SPS, a considerably thin reaction region (~2-3 µm) was observed, elongated polytypoid grain formations were also detected.
Semiquantitative EDX analyses of elongated grains revealed that they may be 15R polytypoid (SiAl4O2N4) phase.
EDX analyses of this phase was demonstrated that these grains could be 21R (SiAl6O2N6) or 12H (SiAl5O2N5) polytypoids.
Acknowledgement The authors would like to thank The Scientific and Technological Research Council of Turkey (TUBITAK) for funding the present work under a contract number of 104T248.

The increase in hardness can be attributed to grain size refinement based on the Hall-Petch effect and the high number of layer interfaces (dislocation blocking strain effects) contribution between TiN and (Ti, Al)N layers.
The diameter of crystal grain can be seen to increase and the bell mouth columnar structures are more obvious along the direction of grain growth.
The grain pattern and size are unregular.
The size of crystal grain is approximately equal in the direction of grain growth.
TiN/(Ti, Al)N multilayer coatings perform the highest hardness in three coatings as a result of grain size refinement and the high number of layer interfaces contribution between TiN and (Ti, Al)N layers. 3) The TiN/(Ti, Al)N coating showed superior performance in the cutting tests.

Plastic deformation leads to a structural refinement by introducing low angle dislocation boundaries and high angle boundaries in the initial coarse grains.
Since the plastic strain is proportional to the rotation number and distance to the sample center [9, 10], it is convenient to produce samples deformed to different strains by controlling rotation number and radius.
A pure Ni (99.5%, purity) with a grain size of 20-60 µm has been deformed by HPT.
The extended dislocation boundaries are dense dislocation walls (DDWs) and microbands (MBs), which are present as one or two sets in a grain.
The appeared strian is indicated by the number in the bracket.

The peak corresponds to PbZr0.52Ti0.4803 (Reference number: 00-033-0784).
The average grain size is reduced with further increases in La3+ content.
It shows that the grain growth has been slowed down by increasing the composition of La3+.
In this case, the higher amount of La3+ reduces the grain size.
Smaller grain size will contribute to an increase of dielectric constant and decrease the tangent loss.

At cryogenic temperatures, at which substantional freezing-out of charge carriers is expected, the number of carriers in the grain volume becomes very small, except the case of very high doping level corresponding to metallic type of electrical conductivity.
Due to this process, the average number of free charge carriers in polycrystalline material decreases and the potential barrier in space-charge region arises.
This is why the laser recrystallization of fine-grained polysilicon is used in order to increase the average grain size and simultaneously reduce the total area of grain boundaries, at which capturing of free charge carriers occurs.
As a result of trapping at grain boundaries, a space charge region (depleted of charge carriers) and the potential barriers appear at grain boundaries.
Laser recrystallization of fine-grained polysilicon increases the average size of grains and decreases the total surface area of grain boundaries responsible for the capture of free carriers.

With the width of the discharge slots 0.5 mm, the size of the crushing products is very sharply reduced due to the fact that their residence time in the chamber increases and the grains are subjected to a large number of collisions against each other, as well as abrasion against the inner surface of the crushing chamber.
REM-photographies a) - grains of diamond micropowders in the range from 200 μm to -40 μm; b) – fine-grained powders of 7 μm or less; c) - submicron powders.
Vibratory sieve is used to classify diamond powders by grain size.
This is due to the fact that some fillers have a large number of pores and micropores or other types of structural imperfections that cannot be measured with a microscope [11].
Assuming that the grains are spheres and the empirical relation d = 6/(γ SBET), which follows from this premise, where d is the grain diameter, γ is the density, we obtain the value of the equivalent grain diameter equal to d ≈ 1.43.

In addition, the grain refinement mechanism of maraging steel during the processing was discussed in detail.
The lath martensitic structure in ferrous alloys is typically characterized by a complex hierarchical substructure which is consist of packets, blocks and laths within a prior austenite grain [2].
In contrast, the values are increased up to 71%, 74% and 80% when further increasing the number of ECAP passes up to 8, 12 and 16 (Figs.2d–f).
Accordingly, increasing the number of ECAP passes results in increased volume fraction of HALB and decreased average lamellar spacing.
Further increasing the number of ECAP passes up to 8 results in the subdivision of the lamellar structure and forms evenly spaced lamellae.

The results indicate that the Ni-Y2O3 nanocomposite coating shows a refined crystal grain and improved corrosion resistance compared with pure Ni coating.
A number of literatures reported that using ultrasonic during the process of electrodeposition could obtain composite coatings with excellent properties such as Zn-Ni-Al2O3, Ni-TiN coatings [13,14].
Compared with the pure Ni coating (Fig. 2a and b), Ni-Y2O3 nanocomposite coating presents a refined crystal grain.
While the nucleation rate exceeds the growth rate of crystal, the grains of coatings become fine[11].
The corrosion process is retarded by proceeding along a circuitous path to reach the substrate due to the finer grain size of the coating.

At temperature of 250 oC, where serrated flows become most obvious, a large number of precipitated phases in slip band were found in micrographs.
The solute atoms formed the mass shadow at grain interior which caused by solid solution treatment.
A small amount of residual eutectic distribute along the grain boundary.
After tensile test at temperature of 400 oC, a large number of dimple appeared in the fracture surface.
In addition, the grain boundary diffusion energy is 92kJ.mol-1 and the lattice diffusion energy is 135kJ.mol-1 [14].Therefore, the deformation mechanism is mainly controlled by the grain boundary diffusion.