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After the extrusion, the alloy presents a bimodal grain structure consisting of fine equiaxed dynamically recrystalized grains with about 1mm grain size and elongated strips of unrecrystallized grains.
Average grain size increased to 5mm after the heart treatment.
The maximum number of cycles was defined as 107 cycles.
Number of cracks observed at specimen surface was summarized in Fig.4.
Fig. 4 Number of cracks observed at the specimen surface during fatigue test.

The larger, elliptoid M23C6 particles mainly precipitate on prior austenite grain boundaries and sub-grain boundaries, while the finer spherical MX particles are precipitated on the dislocations within martensite laths.
The M23C6 particles precipitated on the grain boundaries are elongated along the grain boundaries direction, in which diffusion coefficient relatively high.
Therefore, with the temperature increasing, M23C6 and MX particles which begin to coarsen and dissolve in matrix, can not cause an effective pinning on the grain or sub-grain boundaries and dislocations.
Moreover, in this two-step tempered sample, the size of laths width and precipitates is lower than that of sample S2, while the dislocations density and precipitates number is higher than the latter.
These particles precipitated at early stage can pin the grain or sub-grain boundaries and dislocations, retarding recovery of which at a higher temperature.

As the deformation rate decrease, the lamellar organization in the titanium alloy will convert into the equiaxed grains.
When the sample was compressed for 5.6mm, a few equiaxed grains occurred.
When the sample was compressed for 7mm, a large number of equiaxed grain occurred.
When the sample was compressed for 7mm, a large number of equiaxed grain occurred, this is because that the deformation of powder particles was so sufficient that distortion energy had been produced a great deal, which made dynamic recrystallization carry out completely.
Further compression up to 7mm, a large number of equiaxed grain occurred.

Microcracks propagation is evidently impeded by grain boundaries at low stress level and high stress ratio.
Detailed test procedures (stress level and stress ratio) and number of specimens are shown in the Table 2.
Microcracks slow down or stop near grain boundaries.The fact that microcracks have difficulty in traversing grain boundaries means that the crack plane has some favorable orientation with respect to the slip plane.
Microcrack propagation was clearly affected by the orientation of grains.
(4) Microcracks slow down or stop near grain boundaries.

Introduction Grinding usually can produce excellent surface finish due to a large number of abrasive grains which simultaneously engage in cutting.
In optimization of wheel surface topography to improve grinding efficiency, Aurich et al.[7] conducted simulation of grain distribution on an electroplated wheel.
Although a certain amount of research works has been reported on the development of new grinding wheels by using new types of abrasive grain and performing grain distribution optimization, very few papers have been found on developing a new wheel or tool which can combine the advantages of conventional wheels and cutters.
However, due to the smaller number of cutting edges, the surface roughness obtained by cutting tools is relatively worse than that by grinding wheel.
Acknowledgements The authors sincerely thank the research supports from the Chinese National Natural Science Foundation (Grant Number: 50875225 ) and from the Science and Technology Department of Hunan Province(Grant Number: 2009GK3166).

The deformed state of the region of interest (Fig. 1) contains a number of interesting features related to the texture evolution taking place.
From inspection of the EBSD maps the grains of the <1120> fibre appear more stable in that they contain less evidence of orientation change than the grains of the <1010>fibre.
Not only have these grains rotated by a larger degree but also the GAM of the <1010> grains (Fig. 4) appears to be greater too.
With a greater degree of distortion the grains of the <1010> fibre could become preferred locations for Fig. 4 Grain Average Misorientation (GAM) angle distributions for grains of (red) and (blue) fibres after 10% strain.
Conclusions -Prismatic slip dominates deformation in most grains.

Average grain size of this structure was defined as ~280 µm.
Apart from that, all the grains have grey contrast and grain boundaries are not clear and evident any more.
The formation of stable lamellar flow pattern was more apparent as number of TE passes increased.
Distribution of the average grain sizes was almost homogeneous.
The Office of Naval Research Global (ONRG) is greatly acknowledged for his partial support for the participation at the conference through the grant number N00014-08-1-1011.

Introduction In a number of countries the neutron diffraction method is used on a large scale in solid-state physics and materials research.
Where the distribution of grain orientation is not random we are dealing with a texture.
In number of countries the neutron diffraction method is used on a large scale solid state physics and materials research.
Our project is concentrated to investigation the grain-oriented materials by means of neutron diffraction method.
The determined pole figures are used to calculate the coefficients of expansion Cl µν for expanding the ODF function into a number of generalised spherical functions.

Samples were obtained from the middle portion of the rolled blanks in the number of 3 pieces for one test.
The boundaries of the grains and intergranular delamination, specific to corrosion, are not observed.
Results and discussion On the grain boundaries, dispersion phases can be seen (nanophases of 90 – 200 nm size, see Fig. 6).
In the melt №3 sample, allocating nanoparticles are visible not only at boundaries of grains and blocks, but also inside the grain, which is typical for Mg2Si phase.
The preferred structure of welding seam area using weak pulsed current (WPC) is presented in the samples of melts number 2 and 4, structure of melts number 1 and 3 has defects, but in general microphotographs demonstrates, that microstructure is fine-grained (1 – 10 μm). 2.

This study aims to investigate the effect of temperature and the number of cycle spheroidizing on mechanical properties and microstructure.
In this study, we thus investigate the effect of temperature and the number of spheroidizing cycles in low-carbon steel on mechanical properties and microstructure.
The grain size is 7.9, 6.7, and 5.6μm.
It will have more grain boundaries that cause the grain to be more difficult to move.
It was because of acceleration in recrystallization and grain growth mechanism at the higher temperature, so grain size increased, and grain boundary decreased.