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As shown in a number of papers, this results in acceleration of diffusion processes, and, consequently, the processes of structure transformation start at lower temperatures than in traditional coarse-grained materials.
Its initial grain size was 50 µm.
Subgrains are observed within coarse grains.
Note that the coarse grain size achieves 2 µm, and the volume fraction of grains, 1-2 µm in size, is 40%.
As a result, the activation energy of grains is decreased essentially and the additional stage of rapid grain growth appears on the grain size-temperature curve (Fig. 2).

Thus, the number of nuclei in unit time is increased.
Therefore, the number of crystal nucleus is also increased per unit volume.
Because there are more nucleated grains at 900℃, the austenite grain mainly grows in cooling process.
The nucleus density after finishing rolling at 950℃ is higher than that at 900℃, and the nuclei number increases with increasing cooling rate.
With increasing cooling rate, the undercooling is increased and the nucleation energy is decreased, which accelerates the formation of austenite nucleus, thus the number of recrystallization grain increases and grain size decreases.

The film width can be quantified and its relationship with atomic GB structure can be clarified by studying the thermodynamic properties of premelted GB because the order parameter of PFC is the periodic local number density of atoms.
Mishin, Atomic mechanisms of grain boundary diffusion: Low versus high temperatures, J.
Gleiter, Amorphous structure of grain boundaries and grain junctions in nanocrystalline silicon by molecular-dynamics simulation, Acta Mater 45(1997) 987-98
Cannon, Grain boundary transitions in binary alloys, Phys Rev Lett 97(2006) 075502
Plapp, Phase-field crystal study of grain-boundary premelting, Phys Rev B 78(2008) 184110.

Through increasing the processing pass, further grain refinement can be achieved.
Fig. 3 (b) shows the microstructure in SZ of the single-pass FSP specimen, consisting of the coarse grain band and fine grain band.
After two-pass FSP, the grain is smaller than that of single-pass FSP.
Compared with BM, the number and intensity of β-Mg17Al12 diffraction peaks decrease a lot after FSP because they break up and part of them dissolve into the α-Mg matrix, which is in agreement with the microstructure observation (Fig. 3).
FSP can lead to a remarkable grain refinement in AZ91 magnesium alloy.

Attribute-based encryption (ABE) can keep data privacy and realize fine-grained access control.
It can obtain simple, flexible, fine grained, efficient access control.
First, it randomly selects a number for each user.
First, randomly picks a number , and sets .
When , the attribute number of access policy is 4.

The HPT strain degree was varied by the number of rotations or turns (n) from 1 to 7.
The transformation yield stress for martensitic transformation (sm) of the nanocrystalline alloy with a grain size of 20 nm is about 450 MPa (Fig. 1b), which is three times higher than sm in the initial coarse-grained state (sm » 160 MPa).
It is clearly obvious that sm value increases as grain size decreases.
Microstructure of the Ti49.8Ni50.2 alloy after ECAP 4500C n= 8 (a) and stress-strain curves (b) in the initial state and after ECAP with the same number of passes After ECAP processing ductility decreases, however, remains sufficiently high – about 25%.
The maximum recovery stress σrmax increases with the increase of the number of ECAP passes, achieving 1080 MPa after 8 passes and 1120 MPa after 12 passes, which exceeds the level of the initial condition (480 MPa) by more than 2 times [4].

Textured ZnO-Based Varistors via Templated Grain Growth Ender Suvacı, İ.
Anisometric elongated grains suggest anisotropic grain growth in this sample.
In addition, size of matrix grains increased from 0.2 µm to 6-8 µm.
In addition, as matrix grains grow, driving force for the template growth, which is arisen by surface curvature difference between templates and matrix grains, decreases.
Acknowledgments The financial support from Anadolu University Scientific Research Projects Commission (contract number: 020234) for this study is gratefully acknowledged.

Six different numbers of elements are used to discretise the core area, and the deviations to the maximum PSED values are shown in Fig. 2.
As can be seen from the figure, the PSED value increases with the increase of the number of elements, and converges (< 1%) when the number of elements exceeds about 86,000.
The main feature of the proposed CPFE model is that it takes the size, shape and orientation of individual grains into account, as compared with the traditional CP model which assumes all elements consist of a number of grains representative of the overall texture of the material.
No particular treatment is applied to the grain boundaries, thus the grain boundary effect is entirely caused by the different crystalline properties of neighbouring grains.
Deviations of the plastic strain energy density with increase of element number.

Meanwhile its grain was refined.
The additive ZrO2 made the grain shape of Al2O3 change and the grain size of Al2O3 decrease greatly.
The bigger ZrO2 grains are dispersed on the adjacent of several Al2O3 grains, meanwhile there are plenty of thinner nano ZrO2 grains dispersed in the Al2O3 grains to form the typical intragranular and intergranular structure.
The ZrO2 grains are mainly dispersed on the edge of several Al2O3 grains, and only few white ZrO2 grains are dispersed in the Al2O3 grains.
Most Al2O3 particles are platelet crystalline of hexagonal structure in the area where large number of particles of ZrO2 disperse, while the grains of Al2O3 are big and equiaxial in the area where a few number of ZrO2 particles disperse.

The material was selected because of its grain size which is of the order of 1 µm.
The observed crack shapes are shown in Fig. 3 for three different numbers of fatigue cycles.
This is a direct consequence of the small grain size encountered in this material.
From the K=f(θ) curves, and the experimental values of the crack size at different number of cycles, da/dN=f(∆K) and dc/dN=f(∆K) curves could be obtained.
For Al alloys, it has been shown that fatigue cracks with a size comparable to the grain size exhibit an irregular crack front which is caused by the presence of grains which impede or promote crack propagation.