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At cold deformation of polycrystalline aggregates occurs changing the shape (elongation) crystalline grains and modifying network crystallographic orientation, resulting in a preferential orientation in the direction in which occurs the maximum principal deformation of the body, a phenomenon that is called texturing.
The preferential orientation of grains creates the crystallographic anisotropy, which has the effect of the mechanical anisotropy properties of the material.
The method deformation networks is from the same book [4] it consists in analyzing the structure of the material before and after deformation, considering the body as being composed of an infinite number of material points, with a compact and continuous structure.

The grain size for both specimen ranges from 100µm to 500µm.
Since the elements of Al and Ga belong to the same family with the same number of outer electrons per atom equal to 3, the substitution of Al for Ga atoms in Ni54Mn25Ga21 alloys has no effect on the electron concentration e/a.
The room-temperature structures of Ni54Mn25Ga21-xAlx alloys after heat preservation at 1000 oC for 24 hours are all unitary martensites with the grain size ranging from 100 to 500µm. 2.

With the growth of social economy, a large number of wastes such as steel slag and coal gangue have discharged into the environment.
Sufficient quantity of liquid phase and appropriate grain are produced.
However, the grain will be dissolved if the calcination time is too long, so, that is not conducive to the formation of hard skeleton in aggregates.

Test method The vanadium slag samples taken from the Xichang steel vanadium products factory 1# rotary kiln, temperature control in the reaction zone of the furnace were 500 ℃, 760 ℃, 830 ℃, 840 ℃, 860 ℃ and 900 ℃, The corresponds sample number respectively is SL-1, SL-2, SL-3, SL-4, SL-5, SL-6, Analyse the vanadium slag samples using polarization microscope, scanning electron microscope, energy spectrometer
Observed vanadium slag samples of six groups with different calcination temperatures under polarized light microscopy, the SL-1 sample is mainly including irregular shape, polygonal pale brown vanadium spinel phase shown in Fig. 2; The edge color of vanadium spinel crystal in SL-2 has changed, which is surrounded by gray iron oxide, the heart is still pale brown, crystalline or polygon shown in Fig. 3; The vanadium spinel phase of the SL-3 and SL-4 has not obvious, inside is the wormlike, punctate white ilmenite transition phase, the substrate is calcium vanadate transition phase shown in Fig. 4; SL-5 and SL-6 have not see vanadium spinel, multilateral shape has been completely broken, mainly gray iron oxide and gather grain like ilmenite solid solution phase shown in Fig. 5 and Fig. 6.
The details are as follows: (1)At the temperature of 760 ℃, vanadium slag begins to oxidize from the edge and the phase of oxidation of iron oxide appear; At 840 ℃ vanadium spinel crystal is beginning to damage, oxidized into the ilmenite phase transition and calcium vanadate transition phase; When the temperature is 900 ℃, vanadium spinels have not existed, consists primarily of gray white quadrilateral iron oxide phase and grain like ilmenite phase

It was reported that high W content in the Ni-W changes the grain arrangement over Ni-44 wt.
The W in the crystal structure is transformed into amorphous grains that improve the corrosion resistance [9,10].
Dursta[11] proposed higher surface roughness may reduce the corrosion resistance, interpreted as a large number of defects present in the surface will allow corrosive solution penetration conducive to accelerated substrate corrosion.

After firing at 1400 oC for 15 h, relatively well developed and interlocked whisker shaped crystals having a high aspect ratio >30 (0.2-0.4 μm in diameter) were observed; the grains obtained at 1500 oC for 2 h had a low aspect ratio, compared with 1400 oC.
Souza et al. [7] have prepared mullite whiskers by firing compacts erbia-doped alumina hydroxide and silica gel, at 1600 oC for 1-8 h; the average molar ratio of Al2O3/SiO2 was 1.31, regardless of the Al2O3/SiO2 ratio in the glass phase generated a low value in the mullite grains.
Acknowledgements This work was supported financially by the Korea Energy Management Corporation (Project number: 2005-R-NM03-P02).

The stresses have been evaluated using the measured load applied to the bundle, the mean diameter of the fibres determined in an optical microscope by digital image processing and the number of single fibres in the bundle (supplied by Toray).
A possible reason for these lower values could be the sliding of grain boundaries, which is also confirmed by the numerical value of n indicating Rachinger sliding [2].
The structural origin, which results also in an elongation of the fibres, is probably grain boundary sliding.

Most experimental studies on the specific plastic deformation mechanism of pure Ti have been performed using a number of processing routes such as electropulse quenching [7-9], water quenching (WQ) [8-10], severe plastic deformation (SPD) techniques such equal channel angular pressing (ECAP) or rolling [11-13].
Figure 2 shows the microstructure with large grains, also homogenous refined lath-shaped can be seen, which can be identified to α phase as shown in figure 3.
a) b) Fig. 2 Microstructure of CP-Ti – 100X magnification: a) air cooling ; b) water cooling At a higher magnification, the martensitic transformation appeared in central part of grain and the formed α` phase changed into a relatively refined acicular shape with specific orientation, as shown in Figure 3 and 4, with a significant amout on water quenched sample.

For those samples doped catalytic additives, it can be observed that the large number of acicular α-Si3N4 existed in fracture surfaces.
Obviously, the hexagonal columnar β-Si3N4 precipitated from flocculent α-Si3N4 which was melted edge of grains, it is accorded to the solution-precipitation process.
The intermediary can not be seen in all of graphs because of grain boundary evolution.

The uniaxial simple rules of mixture considered in the following basically assume that strain rates and stresses are uniform over each phase domain, consisting of a single grain or a cluster of grains.
In the two-phase case, the equivalent assumption also leads to one equation more than the number of unknowns.