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Owing to its high dielectric and thermophysical characteristics, chemical inertness and nontoxicity AlN can be used to solve a number of problems in electronics, electrical, chemical and mechanical engineering.
This induces an increase in the self-diffusion coefficient and hence an intensive grain growth during recrystallization.
In this case, plate-like grains form with an aspect ration of 20, i.e. self-hardening of the material takes place.
Many grains contain interlayers constituted by AlN multilayer polytypes.
Molybdenum grains are one order of magnitude larger than the grains of AlN matrix phase.

Alloy composition effected recrystallization of product through the effect of hot rolling plate grain size, then effected magnetic properties.
Supposing everything other component and process remain equal, the iron loss significantly decreased and magnetic induction deterioration was not obvious with the increase of Manganese element and the grain size increases.
Laboratory equipment and Inspection equipment Laboratory test methods and test equipment such as shown in table 1: Table 1 Laboratory equipment production processes test equipment smelt 25kg vacuum inductance furnace forge 650kg forging hammer hot rolling Click the frame 2 rolls reversing mill scouring man-made cold rolling Single frame 2 rolls reversible cold rolling mill anneal Simulation of electrical steel continuous annealing furnace Magnetic detection AC magnetic characteristic measuring instrument MTR -1322 crystalline grain metallographic microscope ODF X-ray diffractometer RINT/2500PC The component design ideas In order to eliminate the corrugated shape defects, the phase change of slab heating and hot rolling, promote the dynamic recovery and recrystallization,the elimination of large deformation grain.
So the P will control in the 0.02% following. 7）In order to improve the effect of inclusions and small precipitates on the grain, and improve the texture of the finished board, Sb segregation element to add a certain amount in steel[4].
Smelting component designs in table 2: Table 2 Design components Number of steel C Si Mn P S Al Sb 1 ≤0.005 1.80-2.00 1.90 0.15-0.35 0.28 ≤0.02 ≤0.005 0.25-0.40 0.30 - 2 ≤0.005 1.60-1.70 1.65 0.65-1.00 0.70 ≤0.02 ≤0.005 0.25-0.40 0.30 - 3 ≤0.005 1.60-1.70 1.65 0.65-1.00 0.90 ≤0.02 ≤0.005 0.25-0.40 0.30 - 4 ≤0.005 1.70-1.85 1.75 0.85-1.20 0.90 ≤0.02 ≤0.005 0.25-0.40 0.30 - 5 ≤0.005 1.70-1.85 1.75 0.85-1.20 1.05 ≤0.02 ≤0.005 0.25-0.40 0.30 - 6 ≤0.005 1.70-1.85 1.75 0.85-1.20 1.05 ≤0.02 ≤0.005 0.25-0.40 0.30 0.04 Test process In a 25kg vacuum induction having be furnaced smelting 6 furnace steel, the alloy steel were analyzed, as shown in table 3.

(6) If the level of grains has few changes for a long time, which means the disintegration is basically stopped and the experiment is complete.
Table 1 and table 2 is the gradual change of grain composition in disintegration testing after the sample ① and ② are submerged in water.
Table1 The gradual change of grain composition in disintegration testing of soaking sample ① dry-wet circle number Different particle composition percentage（%）(unit：mm) <40 <20 <10 <5 <2 <0.5 <0.25 <0.075 1 100 95.20 73.46 36.41 11.26 4.61 2.57 1.22 2 100 91.92 63.46 17.14 6.99 3.85 1.82 4 100 95.86 89.56 27.94 11.96 6.60 4.32 6 100 99.25 91.12 32.16 15.34 10.54 6.67 8 100 99.74 93.02 36.16 16.75 11.26 6.64 10 100 99.74 94.63 46.73 20.25 13.76 8.69 12 100 99.89 95.87 54.65 22.19 14.93 9.46 13 100 99.89 96.27 55.35 22.67 15.91 10.20 Table2 The gradual change of grain composition in disintegration testing of soaking sample ② dry-wet circle number Different particle composition percentage（%）(unit：mm) <40 <20 <10 <5 <2 <0.5 <0.25 <0.075 1 100 48.21 10.17 3.20 1.59 0.83 0.55 0.30 2 100 93.49 61.67 16.63 5.23 2.89 2.18 1.59 4 100 96.71 55.88 10.03 5.14 3.36 2.58 6 100 97.61 81.04 14.87 7.32 5.61 4.11 8 100 98.91 92.19 18.41 8.82 6.73 4.91 10 100 99.10 93.39 25.05 10.28 7.73 5.65
Table 3 and table 4 is the gradual change of grain composition in disintegration testing after the sample ③ and ④ are submerged in water.
Based on the Fractal Theory and the disintegration feature in this paper, the method that the number of fractal dimension can be got by quality is adopted.

The grain refinement in ferrite is usually attributed to the formation of dislocation cell walls, which progressively become low angle grain boundaries, and finally as the strain accumulates to a higher level, transform into high angle grain boundaries [6, 7].
It was also demonstrated that the carbon atoms segregated along dislocations and cell/grain boundaries gave a pinning effect, which finally led to a smaller grain size than in pure iron [6].
(1) where N is the number of rotations and h is the thickness of the sample.
The SAED pattern in Fig. 1(b) was taken from an area with the diameter of 3.5 μm, which displays concentric rings of spots, indicating plenty of nano-sized grains with high angle misorientations have formed; however, singular diffraction spots are still resolved on the diffraction rings, which suggests that a number of cells relatively large in size still remain.
It was estimated that the mean grain size of the ferrite is of the order of 10 nm.

ITTO film deposited at room temperature showed the enhancement in (400) orientation and the increasing in grain size.
With an increase in annealing temperature, the intensity of XRD peak increased and the grain size showed an evident increasing.
Fig. 2 Variations of I(222)/I(400) ratio and lattice parameter (a), grain size and FWHM (b) of annealed ITO and ITTO films.
Annealing can promote crystalline growth, which contributes to the activation of the dopant and reduces the number of donor sites trapped at the dislocations and grain boundaries and increases the carrier concentration.
The grain boundary scattering decreases with the increase in annealing temperature and the growth of grain size.

The hardening effect is achieved through drastic grain refinement down to ultrafine-grained range as well as pronounced substructure strengthening.
This technique promotes the formation a fine-grained or even ultrafine-grained structure in the welded material and thus normally results in excellent mechanical properties of welds.
Typical microstructure of base material: (a) EBSD grain-boundary maps and (b) TEM image.
As expected, FSW led to drastic grain refinement.
Acknowledgements This work is supported by the Ministry of Education and Science of the Russian Federation under the agreement №14.584.21.0023 (ID number RFMEFI58417X0023).

The value of crystallization energy EC calculated with the isothermal method is 517.8 kJmol -1 and the comparison with nonisothermal studies suggests bulk crystallization to occur with an increasing number of nuclei and a two-dimensional growth of crystals.
Initially, the author proposed a DSC (Differential Scanning Calorimetry) study with different grain sizes, a type of analysis that had already been identified by Ray et al., to scan for any prevalently superficial or bulk crystallization.
A part of the glass was ground with an agate ball mill and sifted at different grain sizes (<45µm up to 500-1000µm) for DSC studies (NETZSCH Jupiter, Model STA 449 C).
The DSC analysis at 10°C/min up to 1350°C conducted on a sample with a grain size between 500 and 1000µm allowed TG to be identified at 786°C and TP at 1100°C.
Values of n=1.5, m=0.5 are associated to a mono-dimensional growth of crystals for a bulk crystallization with an increasing number of nuclei, controlled by diffusion, while n=2 and m=1 are associated to a bidimensional growth controlled by diffusion or by a monodimensional growth non-controlled by diffusion.

The microstructure is dominated by large grains (Figs 1a-c).
As the recrystallization temperature increases, new grains shows a clear tendency for coarsening, i.e. they attain dimensions larger than the flat grains/cell widths.
The first one (observed at meso-scale) is composed of thin flat grains.
Coalescence is the process in which two or more neighbouring, slightly misoriented, cells/grains merge to form a single, larger, cell/grain [21].
Acknowledgements This work was supported in part by the Ministry of Science and Higher Education, project ‘Iuventus Plus’ IP2011 036471 and the Polish National Centre of Science, project number 3010/B/T02/2011/40.

A number of micro structural studies have been carried out on nickel aluminide coatings in the last few years [4-8].
There are at least two reasons why grain growth in nanocrystalline materials can be potentially very different from the situation in conventional large grained materials.
Secondly, the physical dimension of the grain boundaries in a nanocrystalline material would limit the formation of conventional second phase particles in large grained materials, and hence the conventional Zener drag mechanism of grain boundary pinning would no longer be applicable.
The contrast of the grains is the diffraction contrast caused by the difference in orientation of the grains suggesting that the samples are polycrystalline in nature.
Conclusions The normal grain growth kinetics under in situ isothermal heating in TEM was analyzed and abnormal grain growth observed in the high annealed films.

Due to the volatilization of PbO, a large number of lead vacancies are formed on the surface of Ba4Pb3O10 phase, which will engender a high interface potential barrier between Ba4Pb3O10 and (Ba,Pb,Sr)TiO3.
Desu believes that the formation of potential barrier on grain boundary related to the association of vacancy and donor segregated on grain boundary [2].
Because of the condition of oxygen abundance on grain boundary, the donors can form mono-ionized barium vacancy and titanium vacancy with oxygen: (× means no charge) × ⋅ +'+→+ O Ba Ba OVSbOOSb 422 2 1 2 32 × ⋅ +'+→+ O Ti Ti OVNbOONb 822 2 3 2 52 The ionic radius of Nb5+ is 0.064nm when its coordinate number is 6, which is close to that of Ti4+ (0.061nm).
The traps capture large numbers of electrons, causing the resistance to increase sharply, which is known as PTC effect.
The rest PbO form BaPbO3 with BaCO3 or BaO on the grain boundary.