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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.

Each element of simulation box is a number zi called spin or orientation which value lies between 1 and Q.
Q represents the number of possible crystallographic orientations of a grain (in this simulation Q=4).
Two adjacent numbers whith different spins constitute the grain boundary.
Moreover the number of spins has to be considered.
Thus we used a 5 mm grain diameter.

Two components in the Mössbauer spectra of nanocrystalline materials were also observed in a number of other publications (see, e.g., [11-14]), where it was assumed that one of them was formed by atoms in the crystallite lattice whereas another one by those in inter-crystallite areas.
This method was successfully applied for the investigation of grain boundaries in a number of coarse-grained materials [17,23-29].
Specified Model of Grain-Boundary Diffusion According to the emission Mössbauer investigations of grain boundaries in a number of coarse-grained metals [17,21-29], there are two lines in the grain-boundary spectra.
NGR Spectroscopy of Grain Boundaries in Coarse-Grained Materials Let us consider what information can be extracted from the Mössbauer studies of grain boundaries in coarse-grained materials.
Nevertheless, in spite of these limitations, the emission NGR spectroscopy is one of the most effective methods of investigation of the state of grain boundaries in UFG materials processed by SPD, and it was used in a number of publications [5,6,49-54].

The grain size of alloys, d, is controlled by the addition of potent nucleating particles (low nucleation undercooling ∆Tn), the number of those particles, �v, the proportion that are active, f, the solute content of the alloy, Q, [4] and the cooling conditions such as cooling rate and superheat when casting into cold moulds [5,6].
Whilst only a small percentage of TiB2 particles actually act as nucleating substrates [4,15], there are a number of things that can poison the grain refining effect.
Hence, reducing the grain size has an effect on a number of competing factors that can result in an increase or decrease on hot tear susceptibility.
A map of the hot tear susceptibility of ternary Al-Si-Mg alloys based on load at solidus measurements (numbers next to points) on the CAST hot tearing rig based at the University of Queensland.
These findings have been collated into a number of guiding points that can be considered by casthouse and foundry engineers when optimising their process operating costs and casting quality.

GRAIN REFINEMENT OF PURE COPPER BY ECAP N.
Heavy deformation was introduced in the samples after a considerable number of ECAP passes, namely 1, 4, 8, 12 and 16.
In the ECAP process, samples with cross section of a square or circular shape can be deformed without undergoing significant changes in the dimensions, enabling significant deformations through an unlimited number of passes within a die.
Theses increments are in accordance with the grain size.
Grain size for the ECAP sample.

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).

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.

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.

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.

Elongated grains were evident at the edge.
Nucleation efficiency refers to the effectiveness of a given type of inoculant with specific physical characteristics and solidification conditions, such as number density, size, size distribution, and cooling rate.
For a given MgAl2O4 spinel crystal size (100-300 nm) in the current study, amount of MgAl2O4 particles present in the master alloy seemed to be satisfying the number density required for efficient grain refinement.
The difference in the grain refinement between ultrasonicated and non-ultrasonicated alloys can be correlated with the change in the number of the nucleating particles.
This increases the number of particles taking part for the nucleation event.