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In some places heterogeneity of plastic deformation is observed even within one austenitic grain.
In some grains micro areas were revealed with the signs of heavy as well as weak deformations.
The latter initiates a formation of new slip bands in the neighboring grains (or subgrains) so that the direction of the new slip bands differ from that in the primary grain.
The microcracks, stopped at grain boundaries, behave unlike slip bands.
Increase in number of loading cycles leads to the addition of external and internal stresses in individual microstructure volumes.

These superior mechanical properties of UFG rare metals can be studied under cyclic loading at very high number of cycles [14] with shear bands [15] forming.
It has not grains and grain boundaries (GB) also.
Light optical microscopy (Fig. 2, a) show that at first pass the grain boundaries forming was started.
Large number of slip system were activated, resulting in the formation of deformation shear bands as observed in Fig.3, b.
At very first pass of ECAP in single crystal start the initial grain boundaries forming.

The average grain size changes with the sintering conditions.
Obviously, the grain growth is restrained during ultrahigh pre- ssure sintering [9].
The grain shape also changes from round-like to irregular with increasing pressure.
ceramics with large-sized grains.
Acknowledgements This work was supported by NSFC of P.R.China under grant number 50272040, Fok Ying Tong Education Foundation under grant number 91046, and Youth Science and Technology Foundation of Sichuan Province.

When sintered at 1450 oC~1500 oC, puncheon-like mullite grains were obtained and a higher temperature corres- ponded to mullite grains with larger size (Fig. 2b, c).
In Fig. 2c, both puncheon-like and sphere-like mullite grains could be observed.
Previous study [12,15] indicates that in spite of platy kaolinite [16], alumina grains can also act as the nuclei for the formation of mullite grains, which may explain the difference in morphology of mullite grains.
We also thank National Key Projects in the National Science & Technology Pillar Program under grant number 2011BAB03B08.
Messing, Development of textured mullite by templated grain growth, J.

Effect of Electroplastic Deformation on Martensitic Transformation in Coarse Grained and Ultrafine Grained Ni-Ti Shape Memory Alloy A.E.
The coarse grained state was obtained by quenching after annealing at 800°C for 1 hour and it formed microstructure with grain size of 80 µm.
As a result total number of the structure defects is decreasing, recovering martensitic transformation.
In this case there is no difference in steps number - both samples have 2-step transformation and no current influence (After cold rolling during cooling we can see only one peak - the second one will appear at lower temperature).
It can be explained by high dislocation density and grain refinement after ECAP

Microstructure analysis demonstrates that the grain sizes enlarge and the number of pores decreases with increasing Cu content.
The whole structure of Sr3YCo4O10.5+δ is loose stacked up by a number of irregular particles, and grain boundaries are not seen clearly as shown in Fig. 2a.
For Fig. 2b, the number of pores decreases, the grains enlarge, and one grain is usually connected with other grains.
Sr3YCo4-xCuxO10.5+δ (x=0, 0.2, 0.4) with higher Cu content, has larger grains and bulk density, less number of pores, which results in the pores in microstructure scattering the carriers weakly and hence increasing the electrical conductivity [18].
With increasing Cu content, the lattice parameters and unit cell volume increase gradually, grain sizes enlarge and the number of pores decreases, and the resistivity at room temperature reduces.

The grain orientation texture and (grain) spatial distribution of, at minimum, 1 mm × 7 mm (RD × TD) EBSD maps of BR_HR and GR_A materials were compared.
This method reduces the total number of experimentally measured points to a set of 2000 equally weighted orientations.
Only the {123} <634> S-oriented grains are shaded in Fig. 3(a) since they constitute the highest volume fraction of grains in the BR_HR material.
Fig. 3(e) shows that the IA resulted in elongated, coarse grains which have an average grain size (determined from line intercepts) of 129 µm (compared to a mean size of 100 µm for all non-Cube, 15° tolerance, grains) and a volume fraction of ∼51%.
Acknowledgment This research was carried out under the project number MC4.05238 in the framework of the Research Program of the Materials innovation institute M2i (www.m2i.nl), the former Netherlands Institute for Metals Research.

The analysis of simulation results has revealed that, due to a wide contact area with adjacent grains and interaction between microstructure elements, more intensive martensitic transformation occurred within larger grains of retained austenite.
The using of SSRVE concept reduced a number of elements within the micromodel in 20 times, while it lowered the calculation time in 16 times.
The large number of elements in the model, resulting in high computing time. 2.
Non-uniform rational B-splines (NURBS) were chosen as a grains representations.
All this entails aggregation of lightly deformed grains by means of other grains, and deterioration of steel mechanical properties later on.

The number of cycles when the ratio between the maximum and the minimum stress reaches 75 % has been defined as the fatigue life Nf.
But the number of cycles to failure is much more important here, probably due to a different thermomechanical treatment.
On the other hand, the other grains exhibit a grid pattern composed of white bands able to propagate through grain and twin boundaries.
Indeed, the more the material is strained, the higher is the number of grains presenting precipitate-free bands.
The two regimes exhibited by the Manson-Coffin diagram are due to the number of grain involved in the two different behaviours for plastic deformation accommodation.

If the ultrafine-grained materials are indeed manufactured industrially, it may offer a great advantage to a wide range of industry, such as light weighting of structures and components, rationalizing a large number of current steel grades, aiding recyclability, and reducing alloy costs.
The optimized SSMR condition provides the ultrafine-grained ferrite of about 1 µm in grain diameter except for a region near the thichness center of the sheet.
The center of the sheet consists of ferrite and bainite with cementite precipitation both at grain boundaries and inside grains.
Summary Ultrafine-grained C-Mn steel sheets with 1µm in average grain size have been obtained by SSMR process, in which the finish rolling temperature is around Ae3.
In addition, more than 80% of ferrite grain boundaries are of high-angle, consequently assuring the increase in strength by grain refinement according to Hall-Petch relationship.