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A comparison with pure Cu shows that the grain size homogenization is shifted towards higher number of ECAP passes.
Depending upon the processing regimes ECAP may influence the microstructure in a number of significant ways.
The total number of indentation prints in each sample was around 130.
%Co solid solution is shifted towards higher number of ECAP passes [5,6].
A comparison with pure Cu shows that the grain size homogenization is shifted towards higher number of ECAP passes.

On the contrary, when the sintering activity is too high, grain-boundary migration is dominant, so grains grow abnormally.
Illustrations are the grain size distributions.
The Weibull distribution function is generally used to evaluate the BDS, which can be described by the following equations[9]: (1) (2) where n is the total sample numbers for BDS measurement, i is the serial number of samples arranged in ascending order and Ei is the corresponding BDS obtained in experiment.
The formation of nanodomains increases the number of domain walls and reduces the energy barrier of domain inversion, thereby reducing Joule loss and thermal breakdown.
(c) BDS as a function of grain size.

Corrosion resistance also increased with decreasing grain size in zirconium at high temperature when nanocrystalline grains were compared to coarse grains [4].
The number following the letter corresponds to the duration of heat treatment time (in minutes).
Figure 1 summarizes the average grain sizes investigated herein and indicates the impact of annealing/heat treatment upon grain size.
The large grains result from slow cooling rates, and the columnar grains form from directional cooling.
Corrosion current (icorr) versus grain size for pure Mg.

With further increase in strain, fine grains are frequently developed in parts of original grain interiors and especially near original grain boundaries.
Under intense plastic deformation at low to moderate temperatures, deformation band are frequently developed and the number and the average misorientation of these boundaries increase with straining [3-9].
The mechanism of fine grains formation may be associate with grain fragmentation process by development of deformation bands.
Repeated deformation leads to increase in the number and misorientation of these bands and finally development of new fine grains in high strain.
Sakai: Ultrafine Grained Materials IV, eds.

Grain Boundary Induced Lateral Propagation of Intermetallic Phases in Nano-Grained Cu-Sn Thin Film Couples Yu.
Introduction In view of technical importance of nanomaterials in the design and fabrication of integrated circuits, a number of fundamental studies concerning reactive interdiffusion in thin metal films [1-5] have appeared in the literature during the last two decades.
The phase formation process begins at the GBs around each grain and then phase front moves towards the grain center.
The propagation rates were sensitive to the grain size in the films: the smaller the grain size, the higher the rates.
Sn concentrations at GB around the grain and inside the grain at the spreading phase front, depend on the grain size.

The range of the flight of a particle depends on a number of factors: its mass, the centrifugal force acting on it, the force of friction on the wall of the hull and the aerodynamic resistance of air during flight.
In turn, the vibration method has a number of disadvantages that can be eliminated by improving its design.
The upper 3 and lower 4 electrodes are located in the same plane and the distance between them varies from 0.2 to 0.3 times the width of the loaded strand of the inclined endless sheet, depending on the number of grinding grains poured from the feeder per unit time, and sorting accuracy.
The reliability of the measurement results in this case is ensured by a large number of scanned grains in comparison with the three-dimensional system.
The curve is plotted as follows: the points corresponding to the numbers of the separator cells are laid off as abscissa, and the shape factor values of the grinding grains are laid off as ordinate.

The numbers in the figure represent the maximum pole intensities
After this processing, each sample, taking A-1 for example, became into three ones as denoted by A-1-1, A-1-5 and A-1-10 (A-1 series) in which the last number represents the holding time (taking minute as unit) of annealing at 270 o C after cold rolling.
The fraction of grain boundaries with different character was determined on the basis of length fraction with the error less than 1.0%.
This is confirmed by the microstructure of early stage of recrstallization as shown in figure 4b in which lot of ∑3 boundaries appear size only around 10 microns, some grains with the same orientation but tend to grow larger by its boundary migration during annealing after cold rolling must be distributed evenly and the space between any two of this kind of grains is very short, it creates the possibility for the coalescence of the SBs clusters.
The initial microstructure which is at the end of primary recrystallization with fine grain size, a fair quantity of annealing twins and a random orientation can definitely result in a final grain boundary character distribution (GBCD) mainly composed of special boundaries (SBs) implying the GBCD has been optimized in satisfaction.

Under tensile conditions, thin specimen exhibit softer mechanical properties when the number of grains across thickness is lower than a critical number and this modification appears above a critical strain level.
Several previous studies reported a softening of the stress when the number of grains across the thickness, characterized by the ratio between the thickness (t) and the grain size (d), is reduced.
A sample is defined as multicrystalline when its number of grains across the thickness is lower than (t/d)c.
Assuming the normality of the plastic flow, the strain path is also modified by the number of grains across the thickness.
This thickness reduction is plotted versus the number of grains across the thickness for each complex loading.

Result also shows that the sandblasting process decreases the grain size of the material.
The increment for 85% of UTS is only 7.13% in number of cycles before fatigue fracture shown in this test.
Table 4 shows the final result for number of cycle before and after sandblasting samples.
Number of cycle achieved Before and After Sandblasting Samples Number of Cycle Before SB Number of Cycle After SB Increment 85% UTS 252029 270000 7.13% 75% UTS 338440 1569119 363.63% 65% UTS 518460 4810958 827.94% SEM.
GRAIN SIZE AGAINST SANDBLASTING TIME The reduction trend proves that the grain size decreases if longer sandblasting process is applied on the material.

The acetification restrains the increase of grain size for CaO as the number of cycles increase.
The grain size of CaO derived from original and modified limestones with the number of cycles can be determined from the main peak breadth in the XRD spectra.
The grain size of CaO derived from both original and modified limestones increases with the number of cycles.
It can be seen that the grain size of CaO derived from original limestone increases more rapidly than modified one with the number of cycles.
And the grain size of CaO derived from modified limestone increases more slowly than original one with the number of cycles increase.