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In A5MS and A5MSZ specimens after 8 pass WMD as shown in Fig. 3(e) and (f), the fraction of dynamic recrystallized equiaxed grains increases with increasing number of pass in WMD process and adding Sc and Zr elements.
While elongation of A5M increase rapidly from 19% before WMD to 36% after 2 pass and maintain constant value with increasing the number of pass up to 8 passes.
(See Fig. 5(b)) In A5MS as shown in Fig. 5(c), tensile and yield stress maintain constant values with increasing the number of pass up to 8 passes.
(process : route B, number of pass : 8 pass, temperature : 673 K) (a) strain rate sensitivity (m) (b) elongation to failure Summary 1.
The A3MSZ and A5MSZ alloy containing 0.2% Sc and 0.1% Zr elements have uniformly distributed fine grain of 2-3 µm in average size with increasing the number of passes.

The results show that, in the grain growth process, most of the spherical second-phase particles located at triple junctions, while the stick SPPs located at the grain boundaries along the grain boundary.
The SPP acts as obstacles to grain boundary movement to retard grain growth.
Phase field model The microstructure of grain growth in phase field model [10] for polycrystalline materials is described by a set of orientation field variables, in order that distinguish different orientations of grains; here P is the integer number of possible orientation.
The average radius of SPPs r=3.3 g.p. , the orientation number P =36, and other parameters m==1.0, =2.0, =1.0.
Then particles appear as black spot, grains are bright and grain boundaries gray.

When the grain boundary is rough, normal grain growth occurs with a moderate rate.
On the other hand, for faceted boundaries, either abnormal grain growth or grain growth inhibition occurs resulting in a duplex grain structure or fine-grained structure, respectively.
Journal Title and Volume Number (to be inserted by the publisher) 3 essentially no movement of faceted boundaries is expected [3,4].
Grain growth is inhibited when the driving force for grain growth is below a critical value, while abnormal grain growth occurs when the driving force is above a critical value for some large grains.
Journal Title and Volume Number (to be inserted by the publisher) 5 The formation and thickening of intergranular amorphous films also affects the growth kinetics of the single crystal.

This paper studies its denoising performance for ultrasonic testing signal with white noise and grain noise, and analyzes the effects of the time-frequency atoms number on denoising performance.
Denoising of experimental ultrasonic signal with grain noise.
To verify the validity of MP denoising method for grain noise and study the effect of the selected atom number on denoising performance, the experimental ultrasonic signal with grain noise is analyzed.
Therefore, grain noise can not be matched well.
In Fig. 3(c), the noise will also increase when the atom number increases, so the interface echoes are almost immerged in grain noise.

The mean austenitic grain sizes were measured and compared.
One of the blocks is at 15 °C, while the other is at 25 °C Journal Title and Volume Number (to be inserted by the publisher) 3 to obtain a temperature difference T.
Conclusions A number of isothermal annealing treatments at 1000, 1050, 1100, 1150 and 1200 ºC were carried out in AISI 304 stainless steels with reductions between 30 and 80%, with the aim of studying the evolution of the recrystallised grain growth.
At lower annealing temperatures the increase of the grain size is still relatively low and only a minor influence on TEP is observed, since the contribution of grain size to TEP is overshadowed by other effects, such as the dissolution of particles.
Journal Title and Volume Number (to be inserted by the publisher) 5 Acknowledgements The authors acknowledge financial support from European Coal and Steel Community (ECSC7210-PR-368).

Firstly, the formula for estimating the bed load transport rate in the bed of sand waves of prototype by model experiment was derived based on the similarity of grain Froude number; Secondly, several model experiments that the bed forms is similar with the prototype were carried, and the formula was verified.
The similarity based on grain Froude number proposed in reference [4], is the method for estimating the bed load transport rate in the bed of sand waves of prototype by model experiment, wherein the Froude number is defined as: where τ* is the dimensionless tractive force including grain resistance and form drag; u* is the shear velocity; s is the effective gravity constant; g is the gravity acceleration; d is the mean size.
The flow condition of ripple or dune bed form that was discussed mainly in this paper is the lower flow regime, and Froude number of flow was less than 0.8.
It could be judged that the bed form was ripple because the grain Froude number of this experiment was less than 20.
The number of large data of τ*e obtained from our experiment was not enough, so it was necessary to bring into the data of experiment done by Shinohara et al.

The alloys can be divided into groups such as the so-called ordered alloys and intermetallides because they have a number of special properties.
The number of atoms in three-dimensional calculated blocks ranged from 20000 to 50000.
The number of displaced atoms in the cyclic mechanism could range from three to several dozens.
The probability of the appearance of cyclic mechanisms including a big number of atoms was increased with the increase of temperature.
A sharp increase of the intensity of diffusion by the three above-mentioned mechanisms and the appearance of collective displacements of a large number of atoms due to grain boundary slipping and intergrain slipping are the most typical phenomena for plastic deformation.

Journal Title and Volume Number (to be inserted by the publisher) a b Fig. 1.
The curved boundary in configuration Fig. 1a can be represented by a number of differently inclined "pure tilt" elements, the boundary in configuration Fig. 1b - by a number of mixed tilt-twist elements with increasing twist component along the boundary.
The driving force was provided by the surface tension of a curved grain boundary: bpa =γ , where bγ is the grain boundary surface tension and a is the width of the shrinking grain.
grain I grain II I I I directions of motion ϕ I ψ Fig. 3.
Journal Title and Volume Number (to be inserted by the publisher) 100 µm 0200 400 600 800 1000 0 100 200 300 400 500 600 Y [µm] X [µm] a b Fig. 6.

Ultrafine grain.
This was attributed to the thermal instability of UFG microstructure; a grain coarsening occurred during a large number of stress repetitions.
Grains with sizes up to a few tens of micrometers surrounded by fine grains were formed after the annealing as a result of discontinuous recrystallization.
In UFGA, however, a large number of smaller damaged areas with macroscale uniform distribution are formed.
After the stressing, large grains with sizes in excess of 100 μm embedded in fine grains were formed.

Grain boundary character evolution during grain growth in a Zr alloy N.
Sample annealed for 15 min at : 600 750 °C Average grain size (equiv. circle diameter) : 5.5 17.3 [µm] Step size for EBSD map acquisition : 0.5 1.5 [µm] Total area of EBSD maps : 2.57 6.23 [mm 2] Number of grains (> 4 pix. ; ≥ 5°) : 83358 20488 Table 2.
In the small grained sample (Fig. 2a), the grains with [0001] tilted towards +TD (i.e.
Grain boundary populations.
With increasing texture strength, the number of grain boundaries between gB and gB' also increases, those orientations precisely having a common <11-20> axis (parallel to RD).