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Currently, a number of characterization methods and techniques are applied for better understanding of γ massive (γm) microstructure, in order to tailor-make microstructures related with specific structural applications.
A number of theories based on the results of electron microscopy has been proposed regarding the formation of the massive grains in TiAl-alloys, these studies have all been performed two-dimensionally [6-8].
In practice, when analysing an orientation map obtained from SEM-EBSD, one can very often see that a number of γ variants are missing.
Even though, the maps do not show any drastic changes in γm grain morphology, the number of grains present in the analysed area is different.
(a) (b) Table 1 The frequency of each γm variants formed arising from one of the γ nucleus Grain Name/Depth of investigation γγγγn γγγγn T γγγγnb 1 γγγγnc 1 γγγγnd 1 0 µµµµm (Number of grains/ surface area) 27/1290 µm 2 14.25/2 µm 2 21/1063 µm 2 31/5258 µm 2 0/0 µm 2 13 µµµµm(Number of grains/ surface area) 24/984 µm 2 0/0 µm 2 27/494 µm 2 33/6332 µm 2 3/33 µm 2 The variant γnc1 arising from the nucleus γn is the dominant variant in Fig 3 (a).

The properties of ultra-fine grained materials are superior to those of corresponding conventional coarse grained materials, being significantly improved as a result of grain refinement.
The specimens were processed for a number of passes up to nine, using a die channel angle of 110°, applying the ECAP route BC.
Considering the billet rotation, different processing routes are possible: route A with no rotation of the billet between consecutive passes; route BA when the billet is rotated counter clockwise 90° on even number of passes and clockwise 90° on odd number of passes; route BC when the billet is rotated counter clockwise 90° after every pass (Fig. 1, b); and route C with the billet rotated 180° after every pass [3].
Calculated accumulated equivalent strain evolution vs. number of passes.
Butu, Mechanical behavior and microstructural development of 6063-T1 aluminum alloy processed by equal-channel angular pressing (ECAP): pass number influence, JOM, 64 (2012) 607-614

There were few dislocations in the grains and in the plate - like shaped g’ precipitates, but a large number of the dislocations were observed around the interface of the plate - like shaped g’ precipitates.
The number of dislocations at the interface increases with increasing the stress.
In particular, a large number of dislocations which are tangled with each other are observed at the vicinity of the interface between the matrix and the plate - like shaped g’ precipitates at 180MPa.
A large number of dislocations is observed at the rafted g/g’ interfaces as well as in the matrix phase near the interface between the matrix and the plate - like shaped g’ precipitates (Fig.8-(c)).
It is supposed that the strain concentrates around the grain boundary in comparison with the grain interior, that is, the drastic creep deformation occurred at the vicinity of grain boundaries.

This exceptional grain-refining ability of Zr has led to the development of a number of commercially important sand casting creep-resistant alloys[5].
For grain size measurement, at least 200 grains were taken.
For the alloy without Zr addition, the grain size is very big with grains size more than 800mm and the grain morphology is columnar.
When soluble Zr is 0.12%, the grain size decreases to 240mm and the grain morphology changes to equiaxed grain, and grain size gradually decrease to 62mm when soluble Zr content reaches to 0.87%.
The Mg-Zr master used contains a significant number of Zr-clusters, which can not be completely broken into individual particles after manual stirring for 10mins.

Can clearly see that strip shape and particulate austenitic distributes in martensitic matrix, a large number of strips were formed between austenite in lath martensite and the original austenite grain boundary, few granular austenite nucleation in martensitic matrix.
There are also a number of dislocation groups exist in that matrix in fig. 3(c).
(2) Upon application of external stress, the soft ferrite grain occurred strong plastic deformation and a large number of dislocations.
The grain became finer.
The grain retained austenite mostly transformed into ε-martensitic, and little stability grain austenite retained in the matrix

In this paper, we study building underground grain storage environment of different areas suitable for degree level, establishment of underground grain storage environment regionalization, has important practical significance.
Fig.2 National underground grain storage suitability rank partition map Conclusion The granary, grain reserve and processing plant built underground, make full use of underground space, from the perspective of sustainable development, food can is in a state of natural low temperature all year round, and implement green grain storage.
Therefore, underground space new green grain storage system research has the vital significance.
Grain and oil storage science and technology communication.
Grain and oil processing.

Description of the influence of austenitizing temperature on the austenite grain size was made using the mean diameter of grain.
Moreover, according to [3], fine grain also influences raising the resistance to creep.
Using the mean diameter of grain, a quantitative description of grain size was made for the parameters of austenitizing applied in the experiment.
For the empirical distributions of mean diameters of prior austenite grains, the number of size grades was established as 11.
Results of measurements and calculations for the prior austenite grain diameter.

In the nugget zone, there are a number of fine recrystallized grains and dispersed precipitates at grain boundaries.
In the thermo-mechanically affected zone, the grain size is not uniform and there are a number of precipitates at grain boundaries.
In the TMAZ on both AS and RS, there are a number of small white η phase particles at grain boundaries, therefore the shape of grains can be identified quite clearly.
It is obvious that grain boundaries are covered by a number of white η phase precipitates.
(2).In the nugget zone, onion rings are evident and there are a number of fine recrystallized grains and precipitates at grain boundaries.

Significant grain refinement was observed after high pressure torsion, while the homogeneity of the grain structure increases with the number of revolutions.
With the continuation of HPT, i.e. with increasing number of revolutions and the increase of shear strain, the fine grained area becomes dominant also at the centre of the specimen and the grain structure becomes more homogeneous, see Fig. 3 and Fig. 4.
The grain structure becomes more homogeneous and finer with increasing number of HPT revolutions.
Initially, i.e. after low number of revolutions, the grain refinement occurs only locally in the vicinity of grain- and twin boundaries.
The hardness values of the HPT samples do not vary with increasing number of revolutions.

When the ASR processed iron is further symmetrically rolled, the grain morphology maintains equiaxed and the grain size decreases to about 0.3 μm.
The grains are elongated along the rolling direction.
During plastic deformation, mass of dislocations form in the grains and slip to the grain boundary and the dislocation tangles.
Many dislocations assemble together and form grain cells to divide the original grains.
Acknowledgements This research is financially supported by the National Natural Science Foundation of China under contract number: 50671062.