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A comparison between the grain structures shown in Figs. 3(a) and 3(b) indicates that the growth speed might be quite different for each recrystallised grain depending on the interface mobility and the stored energy.
After the recrystallisation grains become equi-axed again in Fig. 3(c).
In (b) recrystallised grains are highlighted by different colours and deformed grains in white with grain boundaries shown using black lines.
Recrystallisation nucleation sites were selected using the criterion: relatively high cumulative number of slip system activated during the previous deformation.
Resutls showed that it is possible to simulate the typical recrystallisation textures experimentally observed for rolled FCC and BCC metals using this nucleation criterion by choosing appropriate critical values although the number of possible slip systems for the FCC metal and the method of calculating the number of activated slip systems in this work are different to the ones used in literature.

The germination characteristics such as germination rate, germinating, germination index, vigor index, and content changes of protein and nucleic acid in wheat grain were determined by germination bed method.
The contents of protein and nucleic acid in the grains affect on the seed germination and growth [2].
Germination rate/% = (Germination number / total of grain number for test) ×100% Germinating /% = (Germination number within 3days/ total of grain number for test) ×100% Germination index = Gt/Dv, Gt for germination number in t days, Dt for days Vigor index = G1S, G1 for germination index, S for sum the length of bud plus root Results and Discussions Effect of extract concentration of disused battery on wheat germination Wheat grain was placed in germination bed including the extract of disused battery for 216h, observing swell level of wheat germ every day, recording the change of germination per 100 wheat grains, the results are shown in Fig. 1, x axis is the extract concentration of disused battery, y axis is the germination rate, and z axis is the wheat grain culture time.
The wheat grains were soaked in 0%, 15%, 30%, 50% and 70% of extract concentration respectively.
The synthesis metabolism of nucleic acid is dominant with the increase of cell number during seed germination, the content of nucleic acid in cell enhance quickly.

The grain size continues to increase significantly at 900ºC where the grain size is almost twice than the grain size observed at 800ºC.
The grains are now densely packed to each other with no uniformity in terms of the grain growth.
The grain growth attributed from these two factor would result in the increase in the number of domain walls in larger grains.
The impact of wall movement towards magnetization or demagnetization will be larger than that of domain rotation as the number of domain walls continues to increase.
The presence of greater numbers of domain walls as a result of grain growth leads to the increase in the magnetic saturation.

Mechanical characteristics of the initially cast Al-Mg-Zr and Al-Mg-Zr-Sc alloys as a function of the number of ECAP passes.
As seen from the graphs, the strength of the alloys increases with the number of ECAP passes.
The best result in terms of ductility was achieved with the Al-Mg-Zr-Sc alloy by applying 6 passes of ECAP. 100 150 200 250 300 350 0 2 4 6 8 Number of passes YS, MPa 270 290 310 330 350 370 390 410 430 450 0 2 4 6 8 Number of passes UTS, MPa 20 25 30 35 40 45 0 2 4 6 8 Number of passes RA,% 10 12 14 16 18 20 0 2 4 6 8 Number of passes EL,% Al-Mg-Mn-Zr Al-Mg-Mn-Zr-Sc Fig. 11.
This is considered to be the mechanism responsible for the finer grain structure (with the average grain size of 850 nm) in the Al-Mg-Zr-Sc alloy.
Valiev, in: Recrystallization and Grain Growth, edited by G.

The refinement of grain always companies the refinement of Si particles.
Vast number of finer TiAl3 and TiC particles can be in situ precipitated from melt and homogeneously distributed in melt, which results in the low-Ti aluminum alloys billets being self-refined into the fine equiaxed grain.
When remelted it to produced alloys, high number of the intrinsic TiAl3 and TiC particles existed in low-Ti Al alloys billets are transmitted to A356 melt.
The restricting effect of Ti on the α-Al grain growth is very larger.
The testing A356 alloys have the excellent grain refinement effect and fading resistance.

The abnormal grain growth is well known may be suppressed by a pre-straining treatment.
FSW resulted in drastic grain refinement in stir zone, as shown in Fig. 3a.
The evolved microstructure was characterized by nearly equiaxed grains with the mean grain size of 5.7 mm.
It is clear that the pre-strain suppressed the abnormal grain growth effectively.
Specifically, the pre-strain rolling along the WD was most effective for inhibition of the abnormal grain growth Acknowledgements This work is supported by the Ministry of Education and Science of the Russian Federation under the agreement №14.584.21.0023 (ID number RFMEFI58417X0023).

The C hk.0 and the q1 and q2 parameters have been numerically evaluated and compiled for a large number of hexagonal crystals in [18].
This value can be converted into different average size values averaged over the number (arithmetic) area or volume of coherently scattering objects, especially, if assumptions are made about the shape and size-distributions of these objects [24].
The TEM grain size, in most cases, is rather the average size of regions delineated by large-angle grain boundaries.
This means that with increasing size, in general, the grain size becomes larger then the subgrain size since here the grains can accommodate more then one subgrain.
This result is interpreted by assuming that the vacancy accumulation in the grain boundary region is larger than in the grain interior or matrix regions.

In order to mimic polycrystals as realistically as possible, the well-known Voronoi’s polygon is adopted to generate grains with the mean grain size .
The anisotropy of grains is considered via given orientation of slip planes in each grain.
grain B grain A M O N GB l (a):Dislocation penetration grain B grain A M O N GB l (b): Dislocation emission Fig. 2.
In each grain, two slip systems are arranged.
Acknowledgements The financial support from the Program for Changjiang Scholars and Innovative Research Team (IRT 1027), NSFC under the Grant Number 11172188 and Fundamental Research Funds for the Central Universities is greatly appreciated.

The grain sizes of material were also measured with the comparison method.
Table 2 Material grain sizes Temp[℃] 800 900 1000 1100 Grain sizes grade 9.5 8.5 8.0 7.5 Fracture Roughness Measure Method of Roughness.
The roughness parameters Rc and Ra are related with the grain size of the material for 16MnR steel.
Acknowledgement The research work is supported by Nature Science Foundation of Anhui Province Education Department (Grant Number:KJ2009A126).
The research work is supported by Nature Science Foundation of Anhui Province Education Department (Grant Number:KJ2008A144).

Grain Refinement Mechanism of Al-5Ti-1B Master Alloy by ab initio Calculations HanLong Zhanga, Yanfeng Hanb*, Jun Wangc, Yongbing Daid and Baode Sune State Key Laboratory of Metal Matrix Composites, Shanghai Jiao Tong University, No. 800 Dongchuan Road, Shanghai 200240, People’s Republic of China ahanccyy@sjtu.edu.cn, byfhan@sjtu.edu.cn, cjunwang@sjtu.edu.cn, dybdai@sjtu.edu.cn, ebdsun@sjtu.edu.cn Keywords: Grain Refinement; Al-Ti-B Master Alloy; Interface; Ab initio simulation Abstract.
Introduction Fine equiaxed grains are most preferable for alloys being used at room temperature.
Grain refinement by the inoculation of Al-5Ti-1B master alloy into the melt of aluminium alloys has become the most popular practice in industry [1].
However, their experimental conditions are quite different from the real grain refinement practice in industry.
It is defined as follows: , (2) where Axy is the area of interface, Δz is the increment along Z direction and is the time-averaged number of atoms between z-Δz/2 and z+Δz/2.