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Results and discussion Table 1 is the chemical compositions of the (In15Sb85)100-xBix films prepared at different sputtering powers density and numbers of Bi tablets.
Table 1 Chemical composition of the (In15Sb85)100-xBix recording films using different Sb sputtering power densities and numbers of Bi tablets.
From Fig. 3(a), it is found that the grain sizes are about 15-60 nm and the grains are non-uniform for the annealed In15Sb85 film.
The average grain size of the annealed In15Sb85 film is about 30 nm.
It is found that the average grain size of the annealed (In15Sb85)100-xBix films are increased with Bi content.

The solution annealing at 1080 °C and water quenching resulted in an average grain size of 39 mm.
For subsequent in situ experiments 10 grains were chosen and their surface was carefully documented.
An example of in situ investigations is presented in Fig. 2 for the grain No. 6.
The same observation performed within remaining nine grains showed that PSBs after application of half-cycle were activated in 90% of grains.
This value is much greater than that reported for polycrystalline nickel pre-fatigued to higher fraction of fatigue and it is in agreement with the experimental finding that volume fraction of active parts of PSBs increases with decreasing number of cycles of pre-deformation [10].

The model consists of a single deformed grain into which small recrystallisation nuclei are randomly distributed.
The second term corresponds to the grain boundary mobility.
The number of nuclei per deformed grain for austenite recrystallisation is assumed to be 70.
This is an estimate obtained by calculating the ratio of the average undeformed austenite grain volume to the average recrystallised grain volume in samples quenched after deformation at 850°C, 900°C and 950°C to a strain of 0.5 with strain rate 0.5/s.
Secondly, the local distribution of stress and strain, which exists from grain to grain in deformed austenite and ferrite has not been taken into account.

Tensile testing was carried out on WDW-300E machine to provide numbers of tensile strength, yield strength, elongation, etc.
Grain size of samples at cast state was determined by direct measuring under microscope as (1).
l= (1) where, l: The grain size; L: length of measuring line (mm); M: magnification times; P: number of measuring line across grain boundaries.
This can be attributed to the grain refinement effect of modification agent.
Acknowledges This work is supported by joint research project between Shanghai Institute of Technology and Ningbo Dongdian Electric Equipment Manufacturing Co., Ltd., (Project Number: J2011-50).

The longitudinal microstructure of zinc rod (a, c) and wire made in wire drawing process (b, d) The increase number of draws cause enlargement the grain size for the wire.
During deformation grain size increases from 26 to 63 μm (respectively median is equal 61 and 26 μm).
The grain size was calculated for 100 grains (Fig. 4).
The work was financed by the European Funds- Operational Programme Innovative Economy Number: 5.72180.747 References [1] T.
Narayan, Mechanisms for grain size hardening and softening in Zn, Acta Materialia, 50 (2002) 5067–5078 [5] K.

Materials with ultrafine grains are commonly obtained by means of severe plastic deformation.
Disc precursors of the ordered FePd alloy were processed by HPTD at room temperature under a pressure of 6 GPa and different number of revolutions n = 0, 1/3, 1, 5 and 10.
The broad grain-size distribution (100 – 1000 nm), curvature of the grain boundaries, complex deformation contrast, a considerable amount of dislocations, and plenty of the moire patterns are observed, which indicates a strong fragmentation of grains.
Dependence of Hc of the FePd alloy on the number of revolutions in the as-HPTD state (open symbols) and after annealing at 450оС (solid symbols) Fig. 3.
Disordered subgrains (a) and ordered grains (b).

Equiaxed grains are presented in the annealed Inconel 625 superalloy with average grain size of 81 μm, with some annealing twinning grains, as shown in Fig. 1a.
It is found that the crack is extended along the grain boundary, and that there are a small amount of precipitates in the grain boundary of extruded Inconel 625 alloy tubes (as shown in Fig. 3b), there are also a small amount of precipitates inside the grain (as shown in Fig. 3c).
Since the element of C is strongly affinity with the element of Ni and Nb, the increasing content of element of C and Nb will leading to the increasing number and density of the primary MC carbides of Nb (C, N) and Ti (C, N).
Such carbides are usually considered as crack sources, since large stress concentration is formed between the interfaces of carbides and matrix, during the deformation process. 3) The precipitates appeared in the grain boundaries and inside the grain near the crack are primary MC carbides (as shown in Fig.3b and Table.2) 4)It is also found the primary MC carbides in the grain boundaries and inside the grain in the internal crack( as shown in Fig.3c and Table.2 ).
In addition to these factors above external factors during hot extrusion, the cracks are mainly generated from the grain boundaries or surfaces between the MC carbides and matrix of Inconel 625 superalloy.

With the increasement of the reduction temperature, the grain size of tungsten powder becomes coarse.
Recently, a number of authors investigated the synthesis of tungsten-based powders using different methods, such as the sol-gel method, chemical method co-precipitation, processes of mechanical activation, plasma reduction, and so on [5~7].
With the increasement of the reduction temperature, the grain size of tungsten powder becomes coarse.
Table 2 The Influence of the reduction temperature, the weight of materials in the ceramic boat and the hydrogen flow on the particle size of tungsten powder Number Reduction temperature / ºC Weight of materials in the ceramic boat / g Hydrogen flow / ml.min-1 FSSS of tungsten powder / μm A 800 10 100 1.122 B 750 5 150 0.674 C 650 10 100 0.402 D 650 5 150 0.318 Fig. 2 SEM images of tungsten powder obtained with BTO under the different conditions (Figure A for table 2 number A, and so forth) The influence of the weight of materials in the ceramic boat.
With the increasement of the reduction temperature, the grain size of tungsten powder becomes coarse.

The helical carbon nanofibers with a symmetric growth mode were synthesized with the nanocopper catalyst particles having a grain size less than 50 nm.
Thirdly, the two helical nanofibers are identical in coil diameter, coil length, fiber diameter, cycle number and cross section.
As shown in Fig. 7A, the two helical nanofibers both have two helical reversals, which appear at the coil position of the same cycle number.
From 1 to 3 coils (numbered from the catalyst particle), each nanofibers have tight coil pitch, from 4 coils, their coil pitches become looser.
The helical carbon nanofibers with a symmetric growth mode were synthesized with the nanocopper catalyst particles having a grain size less than 50 nm.

Clear grain boundaries indicated that the alloy had been fully recrystallized.
Grain size of the 7072 Al alloy varied from 1 μm to 3 μm (Fig. 1a).
But the alloy containing 1.5% Ce had a grain size around 1 μm (Fig. 1b).
A quite small number of large ellipsoidal particles with a size of several hundred nanometers could be also found.
The precipitate density dramatically increased and number of large particles decreased simultaneously.