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Fig. 2(b) indicates that the large <111> and <001> grains involve sub-grain boundaries, and some <001> grains have crytallographic orientations nearly identical to those of the neighboring <111> grains in the directions normal to extrusion.
However, the grain size and the fraction of <111> grains increased by the re-solution treatments, as shown in Table 3.
The average grain size and the fraction of <111> grains.
In T7 temper, the coarsening of η precipitates (MgZn2) occurs in grains as well as along grain boundaries, which is associated with the widening of precipitate free zones (PFZ) along grain boundaries [5].
The curves in this figure are drawn by using a phenomenological equation, sa = sao + k{(Nf/Nfo)-m - 1}, where sa and Nf are the stress amplitude and the number of cycles to failure, respectively, Nfo is a reference number of cycles (=107 cycles in the present analysis), sao is the fatigue strength at Nfo, and k and m are constants [3].

Magnetic domain morphology showed that the number of domains increased after heat treatment, the exchange energy  between magnetic domains and the energy of magnetocrystalline anisotropy increased with increasing domain number,thus leading to better coercivity.
The domain orientation increases and the number of domains increases, the exchange energy  between magnetic domains and the energy of magnetocrystalline anisotropy increase.
On the other hand, there are plenty of precipitated phases impeding the movement of domain walls within grains or on the grain boundary [11].
(3) Magnetic stripe was very fuzzy,domain distribution was in confusion and magnetic anisotropy was weak before heat treatment.After heat treatment,The domain orientation enhanced and the number of domains increased,the exchange energy  between magnetic domains and the energy of magnetocrystalline anisotropy increased, meanwhile there were plent of precipitated phases within grains and on the grain boundaries,all the results maked the coercivity better, hysteresis losses higher and ratio of the remanence to saturation magnetization lager.
Temperature dependent mechanical properties of ultra-fine grained FeCo–2V.

The model predictions were confirmed by the experimental measurements that a state of steady nanograin growth can be achieved by designing a certain solute concentration and a proper initial grain size. 1 Introduction Even though nanoscale grain sizes can be fairly easily achieved in many polycrystalline materials, nanostructure stability is a primary concern for subsequent processing and usage. [1, 2] Element doping is an effective way to enhance the microstructure stability of nanocrystalline alloys due to the role of solute segregation.[3] The theoretical predictions about effects of solute segregation [4, 5] have been confirmed by a number of alloys, such as Y-Fe [6], W-Ti [7] and Cu-Zr [8], the mean grain size of the stabilized structure decreases with increasing concentration of the solute element.
and are the corresponding grain interior variables.
is the specific solute excess at the grain boundary, which can be derived as , , and are the solute concentration, thickness and atomic density of the grain boundary.
∆G more negative) than those of other grain sizes.
The mean grain size of initial sample is 40.7 nm.

However, all recrystallized grains are about the same size, implying that these cube grains do not have a growth advantage compared with their neighbours.
They appear on either horizontal or vertical grain boundaries.
Because of the large grain size of the starting material and limited number of grain boundaries after heavy deformation over a very large area, we were not able to quantify statistically the presence of intergranular cube fragments.
Grains are elongated, growing into the two neighbouring grains predominantly along the RD direction.
Some near-cube grains were formed on the boundary between the two grains during the deformation.

Moreover, the number of the precipitates at the grain boundary in the Cu-added alloy was smaller than that in the binary alloy.
All specimens were equal in average grain size, about 150mm, due to the homogenization at 853K.
Also, the average size of precipitates on the grain boundary in the Cu-added alloy was larger than that of the binary alloy.
The number of the precipitates on the grain boundary in the Cu-added alloy was smaller than that of the binary alloy.
Moreover, the number of the precipitates at the grain boundary in the Cu-added alloy was smaller than that in the binary alloy.

The numbers in (b) refer to grain orientations analyzed via EBSD (Table 1).
The numbers in (b) refer to grain orientations analyzed via EBSD (Table 1).
The numbers in (b) refer to grain orientations analyzed via EBSD (Table 1).
However, there were a number of significant differences.
The CA model successfully reproduced a number of the features of the DDRX and MDRX for Waspaloy ingot material.

Load Relaxation Behavior of Ultra-fine Grained Ti-6Al-4V Alloy Y.G.
In this study, superplastic deformation behavior of ultrafine-grained Ti-6Al-4V alloy was investigated on the basis of the inelastic deformation theory which consists of grain matrix deformation and grain boundary sliding.
To date, a number of grain refining processes are extensively reported to fabricate ultrafine-grained (UFG, below 1µm) materials, which lead to achieve superplasticity at low temperatures/high strain rates.
As shown in Fig. 4, the experimental data of CG samples (concave upward) were in good accordance with the lines drawn based on Eq. (3) with an exponent p value of 0.15, which is the same number found in earlier works on 7475 Al alloy and Ti-6Al-4V alloy.
The flow stress curves of UFG Ti-6Al-4V alloy changed their shapes at the intermediate strain rate region as compared to those of coarse grained microstructures, which was mainly attributed to the operation of grain boundary sliding with an aid of grain refinement via ECA pressings.

It can be seen that alumina grain grows up obviously, but its aspect ratio changes a little and the grain shape remains equiaxed.
Under restriction of the matrix alumina grains the intragranular zirconia particles within Al2O3 grains did not coarsen and still dispersed well (Fig. 4b).
With the sliding and rotation of matrix grains, some separated intergranular zirconia grains have chance to approach each other and grow up (indicated in Fig. 4b by small triangles).
Therefore, this fraction of intergranualr zirconia grains retarded the growth of the matrix grains, effectively.
Acknowledgements This work was supported by the National Natural Science Foundation of China under grant number 50375037.

The average grain size was determined from about 500 grains.
a 1 10 100 1000 10000 012345678 Particle diameter in µm Number of particles in 1/mm² 6060hom 6060hetr B 1 10 100 1000 012345678 Particle diameter in µm Number of particles in 1/mm² 6060hom 6060hetr Fig. 1 Cumulative two dimensional size distributions of large particles in the alloy.
The resulting grain sizes after annealing are shown in Fig. 4a.
The recrystallised grain size decreases with increasing strain.
The increase in recrystallised grain size at a strain of 5 to 10, as observed in Fig. 5, is probably related to a critical strain for grain-breaking, accompanied by a significant reduction in nucleation from old grain boundaries.

When the fraction recrystallized, Xrex, is determined, the grain size in the recrystallized regions can be calculated as where is the total number of nuclei.
Here NCube is the number of nuclei formed on old cube grains, NGB the number of grain boundary nuclei and NPSN the number of nuclei from particle stimulated nucleation.
The different nucleation sites are treated independently, so that the total number of active nucleation sites, number of potential nucleation sites and nucleation rate per unit volume respectively, are sums over s = GB, Cube and PSN.
The extended volume fraction of recrystallized grains (which is a key concept of the JMAK-approach), with time-dependent nucleation, is the integral of the volume 4p/3[r(t’,t)]3of grains nucleated at t’ times the number of grains nucleated at t’: , (7) where V and d* are the growth rate and initial diameter of recrystallized grains as given, by Eq. 4 and Eq. 5.
The number of sub-grains that will nucleate during the time dt is the number of available potential nucleation sites (that have not started to grow) , times the increase of overcritical subgrains during time dt.