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The effect of grain size in nanocrystalline alloys is difficult to analyze because challenges of controlling a number of other microstructure factors.
For this purpose, the effects of various microstructure factors on deformation behavior of nanocrystalline alloy need to be better understood, including grain size, grain interior composition, grain boundary composition, and grain boundary width.
As the grain size decreases to tens of nanometers, the deformation becomes dominated by grain boundary instead of grain interior.
At this stage, partial dislocations nucleate on grain boundary, rapidly pass through grain and get absorbed by opposite grain boundary.
Taylor, A unified approach to motion of grain boundaries, relative tangential translation along grain boundaries, and grain rotation, Acta Mater. 52 (2004) 4887-4898

Grain refinement using master alloy is a very good method.
And the number, the size cannot compete with those in the static cast.
Consequently, improved the grain refinement.
And grain refinement using ATB is disabled.
The result of grain size obtained by differently intense stirring show that dendrite breaking should be the mechanism of grain refinement.

This research follows in the experimental testing of connections loaded parallel to the grain.
The thickness of the annual rings and the angle of the grain were also measured.
element, gM is partial factor for material property (gM = 1,3 for solid wood) Conclusion As the number of samples is small, the presented results are prone to statistical error.
This is why a round timber carrying capacity in tension perpendicular to the grain is deciding for the round timber bolted joints carrying capacity perpendicular to the grain.
Acknowledgements This paper has been achieved with the financial support of the Ministry of Education, specifically by the Student Research Grant Competition of the Technical University of Ostrava under identification number SP2014/184.

Fine-grained polycrystalline metals have a very high yield stress and excellent workability.
In recent years, various techniques for producing fine-grained materials with a grain size of less than 1µm have been developed.
Although many SPD processes exist [6-9], the basic grain-refinement mechanism is still unclear.
The cell sizes after the relaxation, the average grain size, and the number of atoms are given in Table 1.
Fig.1 Analysis region Fig.2 Processing route Fig.3 Initial structure Table 1 Cell sizes and number of atoms Cell size [nm] xL yL zL Average grain diameter d [nm] Number of atoms Model S 76.6 2.0 76.4 --- 1,007,160 Model P 76.5 2.0 76.7 22.6 999,356 Table 2 Relationship between processing route and shear direction Rotational angle 1st process 2nd process Zθ Yθ zxγ xzγ zxγ xzγ Route a( A ) °0 °0 - Route b( CZθ ) °180 °0 - Route c( CBYθ ) °0 °90 + Route d( CB-C YZ θθ ) °180 °90 + + Results and Discussions Time Evolution of the Defect Atoms.

In 1966, W.B.Morrison has succeeded in grain refinement to about 1.6µm in 0.13%C steel and showed that such a yielding behavior is taken over even in fine grained steel [1].
The grain refinement below 1.6µm is not so easy but ultra fine grained (UFG) iron has been obtained by consolidation of mechanically milled iron powder [2,3].
Grain size was controlled in the range between 15µm and 70µm.
Sub-number of samples (C30-1 or C30-2 etc.) means the lot number of heat treatment.
It is probably that carbon segregated at grain boundary plays a role to stabilize the dislocation emission site at grain boundary and this leads to the increase in ky.

Building Factor of Grain-Oriented Silicon Iron (3% SiFe) with Different Thickness on 100kVA Three Phase Distribution Transformer Core N.
The winding will be wrap with the number of turn in the model core transformer is 256 turns.
It is clearly can be seen that when using thinner transformer core lamination steel plate, both normal and power loss will reduce in number.
Ideally, the building factor of the transformer cores assembled from grain oriented silicon iron, M4 should be more than 1.
Building Factor Grain oriented silicon iron steel M4, 0.23mm thickness 1.219 Grain oriented silicon iron steel M4, 0.27mm thickness 1.250 Losses reduced using thinner steel plate 2.5% Conclusion The building factor at the operation mode flux density, 1.5T is 1.219 W/kg for 0.23mm thickness and 1.250 W/kg for 0.27mm thickness.

The starting material had equiaxed austenite grains with mean grain size of 35 μm.
This is called grain subdivision which is the basic process of grain refinement by SPD process.
Fig. 4c shows the change in density of low angle boundaries versus number of the ARB cycles.
(b) (a) (c) Fig. 4 Relationship between the number of the ARB cycles and a) the martensite transformation starting temperature (Ms), b) the austenite grain size (boundary interval along ND), c) density of low angle boundaries (2°≤θ<15°) within the austenite.
(iii) The Ms temperature changed depending on the number of ARB cycles.

A number of selective research about γ phase microstructure development of nickel-based single-crystal superalloys are scrupulously expounded further below.
Hao Chen and Xinbao Zhao [10,11] analyzed effect of repair conditions on stray grain formation, low angle grain boundaries, preferable epitaxial growth and crystallography-induced dendrite growth during single-crystal nickel-based superalloy AM3 component repair by laser cladding.
(2) where Γ is the Gibbs-Thomson coefficient, R is the dendrite tip radius, Pei is the Peclet number for i, mi is the liquidus slope, C0,i is the initial concentration for i, ki is the partition coefficient for i, ζc(Pei) is a function of the Peclet number, Iv(Pei) is the Ivantsov solution and Ghkl is the average temperature gradient near the dendrite tip.
Stray grain formation and solidification cracking are preferentially confined to vulnerable [100] dendrite growth region.
Epitaxial laser deposition of single crystal Ni-based superalloy: variation of stray grains.

The starting sheet had equiaxed grains with the mean grain size of 120 µm.
After annealing at 450 ºC, the number of recrystallized grains increased and the area fraction recrystallized was 59%, which was smaller than the 8cycles specimen.
Figure 3 shows a dependence of the area fraction recrystallized on the number of the ARB cycle.
In case of annealing at 400 ºC, the recrystallized fraction hardly changed even when the number of the ARB cycle increased.
Number of the ARB cycle Area fraction of the recrystallized grain /% Fig. 3 Dependence of area fraction of recrystallized on the number of the ARB cycles.

Under high zinc application (5 mg kg-1) the grain zinc content increased by 61%.
Increasing nitrogen application under low zinc fertilizer, the grain zinc mainly comes from the root zinc uptake.
Therefore, the plant nitrogen nutrition may have great effect on wheat zinc absorption, transport and grain zinc accumulation through affecting the number of substances and activity of the above protein and nitrogen-containing ingredients.But so far, researches of the nitrogen fertilizer on plant micronutrients (such as zinc) are rarely reported.
Figure 1 The straw zinc remobilization ratio of wheat plant 2.4 The analysis of grain zinc From table 3 that we can see that when Zn application is 0.2 mg kg-1, the grain Zn mainly comes from absorbing Zn from the soil; when Zn application is 5 mg kg-1, the grain Zn mainly comes from straw Zn.
At grain formation process, the accumulation zinc will be given priority to transfer to the grain, used for the formation and development of grain.