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At high temperatures, grain fragmentation takes place due to frequent formation of kink bands initially at corrugated grain boundaries and then in grain interiors, followed by full development of new grains in high strain.
It has been discussed in detail in elsewhere [7-9] that further deformation to moderate strains leads to increase in the misorientaion angle and the number of kink bands.
Kink bands followed by new grains are scarcely developed in the twinned grain interiors.
When original grains are surrounded by fine grains, kink bands may be hardly developed in the remained original grains, because constrained deformation by surrounding grains can be relaxed by operation of grain boundary sliding and dynamic recovery in the surrounding fine grained region.
The misorientation and the number of boundaries of kink band rapidly increase with deformation, finally followed by the evolution in-situ of new grains with high angle boundaries in high strain

If the model represented a larger volume, with greater time an equiaxed grain structure would evolve from the original ribbon grains and normal grain growth would follow.
Journal Title and Volume Number (to be inserted by the publisher) 7 Deformation Structures Produced with Changes in Strain Path Microstructure Evolution.
In most commercial Al-alloys it is difficult to prevent grain growth when the starting grain size is submicron.
a b c d t = 0 t = 7 t = 22 t = 40 Journal Title and Volume Number (to be inserted by the publisher) 9 Continuous Recrystallization in Severely Deformed Alloys Severely deformed alloys contain elongated grain fragments with an average HAGB spacing (ω ≥ 15°) in the submicron range.
On Ultra-Fine Grained Materials, ed.

Surface defect grains formed on the surface of turbine blades: a) stray grain, b) equiax grain, c) freckle chain grain, d) low angle grain, e) surface pit grain, and f) recrystallized grain.
As already shown in our previous papers [9], each cross section of the surface defect grains showed an intermediate layer composed of elongated γ′ phase with a number of tiny Re-rich particles through the whole cross section.
Most of all, another cross section along the layer (Fig. 2c) clear shows that there are a number of tiny Re-rich particles in the layer.
A high magnification image (Fig. 3b) clearly shows that there are a number of Re-rich particles.
The cross section showed an intermediate layer composed of elongated γ′ phase with a number of tiny Re-rich particles regardless of the formation mechanism of each defect grain, which means that if there is any boundary region in a turbine blade, the layer and secondary phases can be found.

Coarse-grained materials are used more and more widely in modern industry.
This method includes two main contents: Firstly, a number of Intrinsic Mode Functions (IMF) which could describe signal characteristics is calculated from the detection signal according to Empirical Mode Decomposition (EMD).
Firstly, whether the number of the extrema point and the zero crossing point in h(t) are equal or differ by at most one.
Conclusion Because of a large number of structural noise appeared in the ultrasonic test of coarse-grain materials, HHT is presented to process this kind of signal here.
The influence of grain size variation on metal fatigue.

The number of passes can attain 40, and only a low alloy Mg as an AZ31 (Mg-3%Al-0.8%Zn in wt.pct.) with moderate strength is a suitable candidate for sheet fabrication.
In addition, fine-grained Mg alloys tend to significant grain coarsening due to rapid grain growth at elevated temperature.
Journal Title and Volume Number (to be inserted by the publisher) 3 Fig. 1.
Grain size distribution charts for specimens after rolling and static annealing at (a) 250°C and (b) 275°C. 0 10 20 30 Rolling at 300°C (a) Percentage, % Grain size [µµµµm] 1 10 Rolling at 275°C 0 10 20 30 40 50 Rolling at 300°C (b) Percentage, % Grain size [µµµµm] 1 10 Rolling at 275°C Journal Title and Volume Number (to be inserted by the publisher) 5 Fig. 4.
It is seen from a comparison of Figs 1a and 5 that static annealing after IR at 275°C converts the structure of the rolled specimens into the less constrained state: the grain boundaries are more regular after annealing, the dislocations are less visible within the grains, the number of fine particles is reduced within the coarsened grains.

Multiscale Modeling of SPD Processes for Grain Refinement I.V.
Second, the meso-level, the level of grain groups and single grains.
It is devoted to finding out the reasons of the deformation straining, the evolution of the grain size, dislocation density (total, in cell-grain interior, in cell-grain boundaries) and vacancy concentration depending on the SPD conditions.
In connection with this, the ingot material starts failing after a certain number of ECAP passes, when it has exhausted its strain capacity.
It's considered that the reason, why the grains of greater diameter split into a number of substructure elements, is the decrease of the total latent energy stored in the material due to the plastic deformation inhomogeneities.

A relative number of grains with deformation twice as high as the average deformation of the sample has been obtained.
Each square cell of the grain grid here is a model of an individual polycrystalline grain.
The two-dimensional distribution allows defining a relative number of grains with an exhausted plasticity resource.
The relative number of grains with a strain, which is half times more than the average one, increases in a nonlinear way along with a higher reduction rate of the sample (Table 1).
The number of grains, deformations and stress-strain state of which correspond to the selected intervals, were recorded into table cells.

The critical grain holding power of diamond sticks can be calculated by dividing the critical grain holding　pressure by the number of grain based on the specification of the diamond wheel.
As another reported, The number of grains which acts on grinding was calculated by modeling a grain on a cube.[4] It is confirmed that the critical grain holding power of resinoid bond diamond wheel which makes copper the filler is about 0.1N.
(2) 　fc：Critical grain holding power of one grain（N/piece），Fc：The grinding force just before the grain on a wheel work surface is dropping out（N），n：The number of grains which acts on grinding（piece）．
In addition, the number of grains which acts on grinding is calculated by Eq.3
(3) λ：The number of the grains per 1 square mm（piece／mm2），ℓ：The length of the arc which the wheel and the workpiece contacts on the surface grinding（mm），B：Width of a wheel（mm） 　 And, the length of the arc which the wheel and the workpiece contacts on the surface grinding can be calculated by Eq.4

When the number of grains through the thickness is only 1 or 2, the deformation is quite inhomogeneous.
However, the grain number increase to 4 or 5, the plastic deformation is far more homogeneous.
When the number of grains through the thickness is 1 or 2, all grains are located in the surface area and thus only surface grains.
Once the number of grains over the thickness is more than 2, some of which are interior grains and thus interior grain appear.
(2) When the number of grains through the thickness is small, surface grains are in majority and the surface grains constraint dominates the overall roll force.

In order to accurately identify the grain insects, the system required a single-layer grain sample [8].
We only need to collect one image of the grain insects rather than more to complete the detection of one grain sample.
Stored-grain Insects Screening Device and Grain Samples Stored-grain Insects Screening Device.
The dead insects could not be sieve out from the sieve sometimes, and the total number of the insects sieved out successfully was less.
Detection techniques for stored-product insects in grain [J].