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Recently, ultrafine grained microstructures with a grain size of less than one micrometer were obtained after annealing of severely deformed alloys [3-6].
Despite the large number of studies on continuous recrystallization operating in various metals and alloys processed by large strain deformations, some characteristics of this mechanism, e.g. texture evolution, are not known in detail.
In this case, the grain coarsening takes place homogeneously without preferential growth of any individual grains.
Number Fraction, Ni / N 0.0 0.1 0.2 0.3 0.4 0 10 20 30 40 50 60 0.0 0.1 0.2 0.3 0.4 Misorientation, θ (deg) 0 10 20 30 40 50 60 0 10 20 30 40 50 60 ε = 2.0 ε = 4.4 ε = 2.0 625o C, 30 min ε = 2.0 625 oC, 2 hours ε = 4.4 625o C, 30 min ε = 4.4 625 oC, 2 hours Fig. 6.
The development of primary recrystallization associated with grain boundary migration over long distances results in a decrease in the total number of low-angle subboundaries, while the fraction of high-angle grain boundaries increases.

The number and the density of surface defect were increased.
CURM then produced a large number of sub-grains.
With the strain increasing, dislocation cells increased in the number and reduced in the size.
Finally there are many sub-grains within the grain, the size of grains on the metal surface is smaller.
It needed greater resistance to transform, which played the role of grain boundary strengthening, Smaller grain size in the same volume needs the larger number of grains in the same deformation.

For smaller number of turns (N = 1), the Hv increased with distance from the disk center.
The ultimate tensile strength, UTS, and the total elongation, EL, were plotted in Fig. 8 as a function of number of turns.
Some continuous-recrystallized grains were observed.
Fig. 8 Mechanical properties of HPT-processed iron as a function of number of turns.
Langdon: Ultrafine Grained Materials III, TMS, ed. by Y.T.

The average grains size is 7-6 index, when welding without the TMF influence and the average grains size of the weld metal corresponds to 8 index, with separate inclusions of grains with 7 index when welding with the TMF influence.
These data are summarized in monographs [1, 2] and given in a significant number of publications [3-5].
Besides in a number of publications, it is shown that the transverse magnetic field (TMF) use also allows to obtain the above-mentioned positive effects.
Thus, the data on the TMF influence on the weld crystallization in arc welding are few in number.
Electromagnetic stirring and grain refinement in stainless steel GTA welds.

Average squared output error (ASE) decreases with increase of the hidden node number.
The irregular blocky carbide ((Cr0.4Mo0.2W0.2Ni0.1Ti0.08Co0.02) C(1)) with bright contrast indicates that this phase contains elements having higher atomic numbers.
During thermal exposure, particles near grain boundary merge into layer of the grain boundary, which plays the main role in the grain boundary coarsening.
Although interface between the M23C6 particles and layers is not obvious, the cores with dim contrast in the grain boundary should be M23C6 particles due to light elements having lower atomic numbers in composition.
This prevents dislocations from piling up against grain boundaries and in consequence inhibits stress concentration on grain boundaries, when dislocations move to grain boundary.

If it is assumed that nucleation only occurs at grain boundaries, then a given number of nuclei per length of grain boundary in a fine grained material will lead to more homogeneous recrystallisation than the same number in a coarse grained material.
Therefore, a large initial grain size provides fewer nucleation sites due to the reduction in grain boundary area per unit volume.
Note that after a reduction of 50%, the original fine-grained (A) material gave an appreciably finer grain size after recrystallisation than the original coarse-grained (C) material.
However, after a 70% reduction, the grain size after recrystallisation was similar regardless of different initial grain size.
The recrystallised grain size decreased markedly with increasing deformation and decreasing initial grain size.

The starting material had equiaxed austenite grains with mean grain size of 35 μm.
This is called grain subdivision which is the basic process of grain refinement by SPD process.
Fig. 4c shows the change in density of low angle boundaries versus number of the ARB cycles.
(b) (a) (c) Fig. 4 Relationship between the number of the ARB cycles and a) the martensite transformation starting temperature (Ms), b) the austenite grain size (boundary interval along ND), c) density of low angle boundaries (2°≤θ<15°) within the austenite.
(iii) The Ms temperature changed depending on the number of ARB cycles.

And the grain size was 200nm when the KNN powders was synthesized at 700℃.
The powders grain cannot grew up since the grain surface is stable [24].
With the temperature increasing to 800℃, the grain size grew up to 2μm.
The grain growth is consistent with Ostwald ripening.
(°C) Fig.9 Atomic number of the KNN powders sintered at different temperature (700℃, 800℃, 900℃) The amounts of Na, K and Nbatomic ratio in typical sample calcined at different temperatures(700℃, 800℃, 900℃) were measured by XRF in Fig.9.

Building Factor of Grain-Oriented Silicon Iron (3% SiFe) with Different Thickness on 100kVA Three Phase Distribution Transformer Core N.
The winding will be wrap with the number of turn in the model core transformer is 256 turns.
It is clearly can be seen that when using thinner transformer core lamination steel plate, both normal and power loss will reduce in number.
Ideally, the building factor of the transformer cores assembled from grain oriented silicon iron, M4 should be more than 1.
Building Factor Grain oriented silicon iron steel M4, 0.23mm thickness 1.219 Grain oriented silicon iron steel M4, 0.27mm thickness 1.250 Losses reduced using thinner steel plate 2.5% Conclusion The building factor at the operation mode flux density, 1.5T is 1.219 W/kg for 0.23mm thickness and 1.250 W/kg for 0.27mm thickness.

Voronoin method[6,7] is a common method to construct nano-polycrystalline materials: First, a number of points whose Z coordinate are controlled to obey the linear probability density function are randomly generate as the center of the grains,and the distance between grain centers is adjusted to avoid the two grain centers being too close.Then, calling the Voronoin function of MATLAB to generate the grain boundary topology of GNG model.Finally, a C++ script from the literature[8] was developed to fill each grain with the face entered cubic (FCC) copper atom lattice.
The initial positions of crack tips in the three samples are in the grain, along the grain boundary, perpendicular to the grain boundary, respectively.
(4) Figure 2 Schematic diagram of relative crack calculation In the process of tensile deformation, as Fig. 3 shows, a large number of hexagonal close packed (HCP) structures occur in the interior of larger grains and near the crack tip, which reflects the intense dislocation activity and a large number of stacking faults in these two regions.
Heterogeneous lamella structure unites ultrafine-grain strength with coarse-grain ductility, J.
Fracture behavior of precracked nano-grained materials with grain size gradients, J.