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The typical microstructure of the wire is austenitic with nanosized grains (Fig. 8).
The average grain size of the austenitic phase is about 71.3 nm.
The nucleation from austenitic to martensitic is possible because the austenitic grains are nanosized (~ 71 nm) and they are oriented almost the same as the crystal lattice between single grains.
Induced loading or stress on SMA wire enables that austenitic grains start to rotate and plate can grow over the austenitic grains.
Complex deformation by a combination of torsion and bending caused an increase in the number of dislocations and, thus, a higher density distribution of the martensitic plate on the microstructure.

Fig. 1 Optical microstructure of the extruded alloys: (a) Mg-5Y-3 Ni -0.2Zr, (b) Mg-5Y-3Zn -0.2Zr It was found that large number of block-like and lamellar LPSO structure was distributed along with the dynamically recrystallized (DRXed) α-Mg fine-grain.
The DRXed Mg grains about 1-3μm in diameter and LPSO structure about 1-9μm in thickness and 3-41μm in length were observed in Mg-5Y-3Ni-0.2Zr alloy, while the DRXed Mg grains about 1-5μm in diameter and LPSO structure about 1-6μm in thickness and 1-12μm in length were observed in Mg-5Y-3Zn-0.2Zr alloy.
Dislocations piled-up to form kinks when the grain was rotated to the orientation with the negligible Schmid factor for the basal slip in LPSO structure.
Accommodation of large plastic strains and defect accumulation in nanocrystalline Ni grains, J.
Sakai, Dynamic evolution of new grains in magnesium alloy AZ31 during hot deformation, Mater, Trans, 44 (2003) 197-203

The peak stress vs. cycling number curve is given in Fig. 3(d).
Figure 3(f) shows the stress-number (s-n) curve of deformation cycle.
(b) (d) and (f) show the peak stress vs. number curves of the cyclic deformation under three mean strains.
The two images are taken from the same grain under two beam conditions with different operating vectors.
After the saturation of cyclic hardening, the cyclic softening may be attributed to the reorientation of grains [10].

On the other hand in recent time a number of publications aim at the determination of residual stresses by continuous indentation methods [e.g. 7,8].
For the fine grained construction steel S690QL the materials behavior was defined by using a constitutive material model for finite deformations.
In this work they were identified by comparison of experimental data of a set of specific uniaxial tensile tests for the fine grained construction steel S690QL with simulation results.
As a consequence of the tendencies illustrated by Fig. 2(a) and (b) the mechanical properties, which are Journal Title and Volume Number (to be inserted by the publisher) 5 determined using characteristic values of the force indentation depth curves are clearly affected by the imposed prestresses.
Mech., A22 (2003), p. 309 Journal Title and Volume Number (to be inserted by the publisher) 7 [17] T.Y.

In this case the substrate remains unaffected by the grain penetration.
On the other hand, in the bottom figure part, the FEM calculated stress fields correspond to a larger grain size of 100µm radius, whereas the grain penetration depth amounts to 450nm.
The applied impact loads were 30, 60 and 90 daN and the number of impacts was set to 10 5, 4x10 5, 106 and 3x10 6.
In order to provide an overview of these tendencies at various impact forces and number of cycles, numerous impact tests and nanoindentations were conducted and the related results are displayed in fig. 5.
In both cases, these courses remain independent by the number of impacts. 4.

For large values of the buoyancy number the solute buoyancy forces prevail over thermal ones.
Consequently, prior to the solidification stage the buoyancy number was around 28 and the natural convection was almost completely suppressed despite the application of a thermal gradient.
The dendrite fragment serve as nucleants for the solid phase and increase of their numbers promotes finally a finer solidified structure as shown in Fig. 6.
Besides the macrosegregation and channels, the effect of thermo-electric magnetic forces on the transport processes results in the re-organisation of the grain boundaries which happens preferentially in the deep mushy zone.
A striking example of a grain boundary organization into a peculiar ring-like structure is shown in Fig. 9 [7].

This number is based on a sensitivity analysis performed repeatedly for different workpiece materials.
For 41Cr4 steel and selected values of and this number is optimal value.
View of: a) Huber-Mises-Hencky’s intensity stress for the initial stage of the process, b) graph of displacement of node number 53170 on the Y-axis Case 2:  µm, .
Kukielka, Numerical analysis of micromachining of C45 steel with single abrasive grain, GAMM 79th Annual Meeting of the International Association of Applied Mathematics and Mechanics E-Publishing (2008) Bremen
Kukielka, Numerical analysis of the influence of abrasive grain geometry and cutting angle on states of strain and stress in the surface layer of object, in J.T.M.

The microstructures of the Ti-30Nb-xZr alloys had an equiaxed grain structure, in which the needle-like α phase precipitated at the boundaries of β-phase grains, as seen in Fig. 1(c).
At higher Zr content, precipitation of α-phase also occurred in the interior of the β-phase grains.
The two Ti-30Nb-xZr alloys had smaller numbers of micropores and nanotubes on the surface (Fig. 4c and d) compared to the two Ti-30Ta-xZr alloys (Fig. 4a and b).
The size and number of micropores and nanotubes should be important for clinical biomaterials use.
The Ti-30Nb-xZr (x = 3 and 15 wt%) alloys had an equiaxed structure, with smaller numbers of micropores and nanotubes compared to two Ti-30Ta-xZr alloys.

Introduction Titanium alloys have been widely used in a large number of industrial applications due to its high specific strength, good corrosion resistance as well as its high thermal stability [1, 2].
In addition, TiAl3 is also an effective grain refiner since it acts as the nucleus of α- Al during the refinement of aluminum alloys [5-8].
One main purpose of this work is to investigate the correlation between the adhesion and atomic or electronic structures of the TiAl3/Al interface by means of density functional theory, in addition of its appeal from a basic science standpoint, the final motivation for the study is to explore the grain refinement mechanism of Al-Ti-B master alloys in the future research.
Two parameters that affect the accuracy of calculations are energy cutoff, which determines the number of plane waves in the expansion, and the number of special k points used for the Brillion zone integration.
Using x-ray diffraction measurements at a synchrotron source and a quenching melt spinning technique, the heterogeneous nucleation of Al grain is found that metastable TiAl3 phase on TiB2 surface acts as the nucleus of α-Al.

Whereas the isothermally oxidised samples exhibit surface roughening [Fig. 2 (b)], arising from the original as-deposited NiAl grains [Fig. 2 (a)], the cyclic conditions seems to promote spallation and the formation of wrinkles [Fig. 2 (c)].
The additive layer thickness decreases with the number of cycles as does the interdiffusion layer.
The drop of the Al content to reheal the oxide scale that spalls off with the number of cycles, bring about significant β to γ' transformation accompanied by volume contraction [12, 14].
It appears that isothermal conditions favour surface rumpling whereas wrinkles develop with the number of oxidation cycles.
However, the wavelength remains close to the original NiAl grain size.