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Finally, the hardness values are reasonably homogenous along the disc diameter as the number of turns increases to 5 and 10 turns.
There are some reports on the grain refinement during HPT processing of Al-5% Mg [9] and Al-1% Mg [10].
The grain structures in the HPT-processed Al-0.1% Mg were also examined by EBSD using a JSM6500F SEM.
Fig. 3(a) shows the disc centre area has coarse grain structures but with higher number fractions of low-angle boundaries introduced by HPT shear deformation.
Langdon, Principles of equal-channel angular pressing as a processing tool for grain refinement, Prog.

For these alloys a grains with orientation of {111} and {100} grow much faster than grains {113} and particularly {110}.
For the ω-geometry, we have d=[(V p Phkl dβ ∆ω)/ 4πn] 1/3 (1) where V is the irradiated volume, p is the multiplicity factor, n is the number of crystallites with different orientations, Phkl is the pole density of the (hkl) reflection in the inverse pole figures, ∆ω is the measured angle range in the rocking curve, and dβ is the vertical divergence of the Xray beam.
Then the grain size value for this grain can be obtained from Eq. 1: di =[(V p Phkl dβ ∆ω)/ 4π] 1/3 (Si/ΣSi)1/3 (2) This approach [1] allows the determination of the fraction of recrystallized grains (fr) and of the grain size distribution for any grain orientation.
The grains with orientation of {111} and {100} grow much faster than grains {113} and particularly {110}.
At the same time the grain size of "textured" grains is much lower - (220) and (311) reflections on Fig.2b.

Introduction Some polycrystalline materials show very high tensile elongation prior to failure when a number of microstructural requirements are fulfilled [1].
As-quenched Zn-0.3Al alloy is composed of coarse-grained η-phases having a grain size ranging from 100 μm to 250 μm (Fig. 1(c)).
Furthermore, α-phase grains with ~110 nm are mainly located at the boundaries of η-phase grains having ~540 nm grain size [5].
ECAP leads to a significant grain refinement in the η-phase grains of Zn-0.3Al alloy.
The mean grain size of the η-phase grains is about 2 μm.

Ensuring Strength of Fine Grained Concrete with Mixed Cement Binders A.
Yung it has been proven that hardened cement stone contains a large number of unreacted cement grains, which can be replaced without loss of strength with the corresponding fractions of mineral additives.
In modern construction, the use of fine-grained concrete (FGC) is due to its special properties compared to traditional heavy concrete.
Purpose of the Work Ensuring the strength of ordinary fine-grained concrete with the rational use of cement.
However, this indicator is equalized by the number of CASB with its maximum amount (х2=+1) in concrete 400 kg per 1m3.

Introduction Over the last decade, a number of techniques collectively referred to as severe plastic deformation (spd), have emerged as a promising approach for the production of bulk ultrafine-grained (ufg) materials [1].
As expected, grains were severely elongated in the region recognized by the number 2.
The grains in the region are highly elongated, showing extensive plastic flow.
Formation of shear bands may explain as follows: elongated grains along the shear bands are generated in the favor path which depends on die geometry and billet size and then fragmentation of (a) (b) Adiabatic shear band 1 2 3 the grains into equiaxed smaller grains.
The shear bands contained much finer grains compared to the bulk materials.

Experimental results show that a considerable number of spherical γ’ phase distributed uniformly under solution at 982℃ solution for 1h and 718℃ aging for 1h.
Results and Discussion Microstructures of GH2132 after different aging treatments are shown in figure 1.Figure 1(a) displays equiaxial polygon grains after aging treatment and the grain boundaries are clear.
The carbides not only reduce the binding force of the grain boundary and damage the continuity of the grain boundary, but also become a source of crack and make the alloy occur brittle fracture.
(2) After the secondary aging, large particles of carbide precipitation appeared in grain boundary, which not only reduce the binding force of the grain boundary and damage the continuity of the grain boundary, but also become a source of crack and make the alloy occur brittle fracture.
This paper is supported by Guiyang Municipal Science and Technology Project (Contract Number (2012207)03,(2012101)2-5), and Guizhou Industrial Research Project(Contract Number〔2014〕3018), Guizhou Provincial College Special Engineering center for Materials Protection of Wear and Corrosion , College of Chemistry and Materials Engineering, Guiyang University Project(KY[2012]023) References [1]Chen Qi, Chen Ya-wen, Kong Fan-ya.

The several numbers of methods using external forces have been applied to introduce fluid flow during solidification of molten metal in casting process.
Microstructure of the ingots cast with the conventional Direct-Chill method exhibited relatively fine dendrite grains at the surface area, but coarse dendrite grains at the ½ radius and large equated dendrite grains at the centre.
Globular grains were obtained in AZ91 alloy subject to high intensive ultrasonic vibration.
The grain size was reduced gradually from 202µm to 146µm with increasing ultrasonic power [21].
The result shows that the long dendritic silicon phases are split into number of particles [22].

The results indicate that surface melting and grain refinement were found in the melted surface layer.
Remelting and grain refinement in the surface layer is mainly responsible for healing fatigue damage and fatigue life improvement.
Fig.1 reveal that fatigue damage was healed completely under conditions 1, selected different pulse numbers and conditions 2, pulse number of 1.
The small grains are, the more grain boundaries of copper film specimens have.
Plenty of grain boundaries could hinder the generation and movement of dislocations, which delay fatigue crack initiation.

The orientation distribution functions (ODF) for the 2 % Si steel 9 % cold worked, 9 % cold worked and annealed for 5 min in salt bath at 760ºC were determined, but the ODFs of the annealed samples for 10 and 30 minutes after cold working are not useful since the material presented very large grains (with an average diameter of about 300 µm, as shown in Fig. 1d), and, therefore, in a small number, which leads to pole figures that are statistically unreliable.
The produced CSL histograms and the grain orientation between grains for the samples are those for the longitudinal section, here not reproduced for reasons of space.
Furthermore, these grains may be consumed through the growth of other grains before nucleation starts.
Due to the high cold rolling reductions, grain boundary density is high so that there is a considerable amount of SIBM grains.
Therefore, it seems reasonable to suppose that the appearance of the exaggeratedly large grains occurs by recrystallization, starting in the more deformed grains and consuming the grains with orientation close to {011}<100>.

At room temperature the alloys (particularly Al-Mn) exhibit significant grain refinement by grain fragmentation leading to "grain sizes" of less than 10µm.
After multiple forging to strains of order 3, both EBSD and X-ray diffraction indicated the development of a well-defined crystallographic texture of which an example is given by the pole figures of Fig. 3 (composite Al-Mn sample to cover a large number of grains).
Over the length scales of 100-200µm, grains are seen to develop by fusion of several, previously separate, grains.
The difficulties of quantitatively characterizing as-deformed grain sizes in large-grained material are well known.
At room temperature the alloys (particularly Al-Mn) exhibit significant grain refinement by grain fragmentation leading to "grain sizes" of less than 10µm.