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This difference in groove numbers and maximum groove depths relatively corresponds to the difference in grain density and ha values shown in Fig. 4 and 5, respectively.
LGS also shows more aligned grain distribution with respect to z, compared to MGS. 500 µm Max. 35 µm 50 µm Max. 50 µm (b) MGS (a) LGS Ground depth, z Ground material width, r The number of grooves：9+1.5 mm-1 The number of grooves：6+0.5 mm-1 Figure 6.
The difference in ground groove numbers corresponds to the difference in grain density between LGS and MGS.
Thus, the number of ground grooves is calculated as Nge(z) x L, assuming all the effective grains on a GS surface form continuous groove lines.
As it is mentioned in profiles in Fig. 6, LGS forms higher number of grooves and more aligned grooves on a ground material surface than MGS.

UFG structure with an average grain size of ~0.3 µm was produced in Cu billets by TE processing.
There were also wellshaped grains.
The Summary of mean values of mechanical properties with number of TE passes increasing is shown at Fig. 8 a. 0 1 2 3 4 0 100 200 300 400 0 20 40 60 80 100 YS UTS YS and UTS, MPa Number of TE passes Elongation Reduction in area Elongation and Reduction in area, % 0 2 4 0 2 4 6 8 V, % Number of TE passes YS UTS Elongation Reduction in Area (a) (b) Fig. 8.
Valiev: Nature Materials, Vol. 3 (2004), p.511 [2] Ultrafine Grained Materials III.
Varyukhin: Ultrafine Grained Materials III.

Relationship between Fabrication Temperature and Microstructure Evolution The migration velocity (v) of grain boundaries can be given by the following equation [1]: (1) where A is the accommodation probability, Z is the average number of atoms per unit area at the grain boundary, Vm is volume of specific mol, Na is Avogadro’s number, h is Planck’s constant, R is the gas constant, T is absolute fabrication temperature, is the activation entropy, Qa is the activation energy, is grain boundary energy, and r is grain boundary curvature radius.
And its grain-boundary energy is J.
N is the sites number of the simulation domain. n is the solid-phase site number around one specific site.
The attempted N (total site number in the simulation system) times is regarded as one Monte Carlo Step (MCS).
The simulation time is expressed in term of the number of MCS.

Data were collected at a sufficient number of points within each cycle so as to obtain the detailed response of orientation-specific grain groups.
Cycle numbers for unloading analysis also are shown.
-400 -300 -200 -100 0 100 200 300 400 0 0.5 1 1.5 2 2.5 Cycle number hkl microstrain 111 200 220 311 Fig. 3.
The evolution of orientation-specific residual elastic strains as a function of the number of cycles.
Evolution of residual strains (hk.l), and the difference strain 100 001ε ε− , with the number of unload (see text).

A large number of investigations have examined the effect of different deformation and annealing conditions (temperature and time).
For the grain size measurements, both the average size of all grains, and the average size of only the grains with orientations within 15 o of <001>{100} were determined.
The solid line is the average value for annealing without magnetic field. 0 10 20 30 40 50 60 70 80 90 8 12 16 20 24 28 Grain size (µµµµm) Angle to magnetic direction cube grain size all grain size Figure 4.
The results suggest that the presence of the magnetic field results either in retardation of grain growth, or in an increase in the number of recrystallization nuclei.
Acknowledgements This work was supported by the National Natural Science Foundation of China under contract numbers 50474087 and 50231030.

Fig.1 Example of whiskers that have grown from a tin-plated brass component Background Investigations into whisker growth date back at least 50 years [1] and have established a number of conditions relating to their growth: • Whiskers are single crystals of normal (tetragonal) tin structure [2]
The growth axes of a number of whiskers were determined by shaking these free in an ultrasonic bath and then depositing them on an SEM specimen holder for EBSD measurements.
This, as well as other local measurements demonstrates that there exist high angle grain boundaries between the whiskers and the grains from which they grow.
In virtually all cases the whisker is seen to end as a cone where a high angle grain boundary separates it from the tin grain(s) in the coating below.
By contrast, there is no evident grain growth in the coating layer, even over months of storage.

The same length is applied to calculate the fatigue-effective stress and strain (averaged over ao length), the fatigue damage parameter PSWT, and finally the number of load cycles Nin for the growth step n.
At the weld notch, coarse-grained HAZ was observed.
Consequently, the grain size at 99% probability level is significantly larger, as is the volume-weighted average grain size dv.
The Hybrid has a pronounced peak at low grain sizes.
Figure 4: Relation between Martens hardness and different grain sizes: a) volume-weighted average grain size [7], b) grain size at probability level of 99% (PF = primary ferrite, P = pearlite, AF = acicular ferrite).

Even if the number fraction of larger grains in the nanostructure is low, their volume fraction can be sufficiently high to contribute to dislocationbased plasticity in the material [1].
As already demonstrated in many metals produced by ECAP, the grain size reduction can be roughly described by the "fragmentation" of the initial grains and the creation of sub-grains having an increased amount of misorientation with increasing strain; thus leading to ultrafine grains separated by high misorientation boundaries (Fig. 1a to 1c).
Figure 1 Evolution of the microstructure with increasing number of passes (route Bc) of ECAP: (a) 1 pass, (b) 2 passes, (c) 8 passes and (d) 12 passes.
Figure 2 shows some tensile engineering stress-strain curves recorded on the ECAP-Cu samples deformed at different number of passes.
It is clear from Fig. 2a that the strength of the material increases gradually with the number of passes from 1 to 8.

The eutectic lamella phase was refined by the extrusion; the grain size of the α and β phase was measured to be a few micro-meters.
Then, direct extrusion was carried out at 573 K to obtain the extrusion composed with fine matrix grains.
Refined matrix grains and dispersion of β phase were confirmed by microstructure observation and XRD analysis. 3.
Acknowledgement This work was partially supported by the Funding Program for Grant-in-Aid (Grant Number 25246012) for Scientific Research from the Japan Society for the Promotion of Science (JSPS).
Sherby, Low Stress Creep of Fine-Grained Materials at Intermediate Temperatures: Diffusional Creep of Grain Boundary Sliding?

Parameter RG582 PR9 Grain number [n] 176 220 Avg.
Regarding the grain number, it can be noticed from table 3 that there is an obvious relationship correlates grain number with Average diameter of granules.
Parameter RG582 PR9 Grain number (n) 176 220 Avg.
Therefore, a number of these grains is moving to form sub mono-layer as shown in figure 3.
In terms of granularity accumulation distribution report, table 5 shows the number of grains for reforming catalysts (RG582 and PR9) based on volume % and number of grains (176, 220 respectively).