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Fatigue crack initiated from specimen surface, when number of cycles to failure was shorter than 106 cycles.
(b) indicate typical coarse grains.
The MDFed Ti is composed of homogeneous ultrafine grained microstructure with the average grain size of 200 nm.
Figure 2 indicates the relationship between stress amplitude, σa, and number of cycles to failure, Nf, in the fatigue tests, called S-N diagram.
Surface crack initiation was also recognized in the MDFed Ti, when number of cycles to failure was shorter than 106 cycles.

Equation 4 assumes that the number of atoms in the actual and control simulation cell are the same.
The area of each grain is proportional to the number of atoms in each grain, the proportionality being the area per atom, ao.
To calculate the number of atoms in each grain, an atomic orientation order parameter ηi is used to define the orientation, and therefore the grain identity of each atom.
The number of atoms involved in each such shuffle is directly related to the atomic-structure of the grain boundary.
Typically, the number of atoms in each shuffle as well as the shuffle frequency increases with the symmetry of the grain boundary, and the temperature.

Introduction Reactive Ion Etching(RIE), is a kind of dry etching process which is assisted by plasma which is an ionized gas with equal number of positive and negative charges.
Table 1 : Maximum and minimum value for parameters Parameters -1 1 Oxygen 20 sccm 50 sccm Argon 30 sccm 80 sccm ICP power 500 W 1 kW BIAS power 100 W 300 W Next, the wafer is prepared whereby it is diced to get the number of samples needed for the DOE.
Fig. 2: Mean Grain Size Analysis before RIE Fig. 3 shows the statistic of the mean grain size for 16 experiments after RIE.
Fig. 3 : Mean Grain Size Analysis after RIE Consequently, this preliminary study presents that the RIE treatment results in increment of the grain size.
Overall comparison between grain size prior RIE treatment and after RIE treatment shows that grain size of aluminum increases after RIE treatment.

Fig. 1 Gravels in conglomerate layer Statistical Analysis of Grain-size Characteristics of Gravel Statistical Method of Gravel Grain Size.
This paper divides different particle sizes of gravel into grain groups, and statistics and analysis of the quantity, volume and their percentage of each grain group are carried out.
Table 1 Statistical Summary of Gravel Grain Size group quantity percentage（%） volume percentage（%） cumulative quantity percentage（%） cumulative volume percentage（%） <30mm 32.99 3.97 32.99 3.97 30-40mm 21.01 10.00 54.00 13.97 40-50mm 20.08 15.78 74.07 29.76 50-60mm 10.13 13.05 84.21 42.80 60-70mm 4.37 7.63 88.57 50.43 70-80mm 3.86 9.71 92.43 60.15 80-90mm 3.46 11.98 95.89 72.13 90-100mm 2.78 13.81 98.66 85.94 >100mm 1.34 14.06 100.00 100.00 total 100.00 100.00 Fig. 3 Quantity and volume percentage Fig. 4 Cumulative quantity and volume percentage From the Fig.3 we can see that the number of 30 mm below is the largest and the number of more than 100mm is the least.
The number of 30-40mm and 40-50mm size is about one fifth of the total quantity respectively.
This paper divides different particle sizes of gravel into grain groups, and statistics and analysis of the quantity, volume and their percentage of each grain group are carried out.

From the literature it is known that with increasing number of ECAP passes, after an initial formation of ultrafine cell boundaries, the grain size nearly remains constant, but the misorientation between the grains increases, see e.g. [15].
After ECAP deformation, irrespectively of the number of ECAP passes, the microstructure contains areas with nearly equiaxed ultrafine grains and shear bands with ultrafine elongated grains.
However, the SAD patterns show a more pronounced ring-like structure with a higher number of ECAP passes, indicating that the misorientation between the grains and therefore the fraction of high angle grain boundaries has increased.
With a higher number of ECAP passes the fraction of high angle grain boundaries increases and consequently, the cyclic stability of the UFG microstructure also increases.
TEM investigations have shown that after 4, 8 and 12 ECAP passes the grain size nearly remains unchanged, but from SAD patterns it has been concluded that the misorientation increases with a higher number of ECAP passes.

Retardation Effect of Grain Boundary Segregation on Grain Boundary Diffusion B.
The effect of grain boundary segregation (GBS) on grain boundary diffusion (GBD) is analyzed in frame of the new model.
Their composition is close to that of the nearest phase in grain in equilibrium with solid solution in grain.
In a number of systems with strong interaction (e.g, Ni-S, Fe-S, Ni-P) [12-14], it was shown that such associates are formed.
[2] Grain Boundary Diffusion and Grain Boundary Segregation / Ed.

Conductivity of Grains and Grain Boundaries in Polycrystalline Heteropoly Acid Salts B.
The contribution to conductivity by grain boundaries is higher than that by grains.
Salts of small-weak cations crystallized with a large number of water molecules (25-17) and those of big-strong cations form precipitates with lower hydration degree [11].
These RC circuits correspond to grains and grain boundaries.
The conductivity of grains is higher than that of the grain boundaries.

Particle - grain boundary pinning configuration is well studied [1-2].
Simulation procedure MC simulation of grain growth is well introduced [4].
N is the number of sites in the microstructure.
Journal Title and Volume Number (to be inserted by the publisher) 3 0 2000 4000 6000 8000 10000 12000 14000 16000 0 100 200 300 400 500 600 700 Time (MCS) Grain area (sites) particules : elongated circle square 200x200 fraction 5% random spread (a) 0 2000 4000 6000 8000 10000 12000 14000 16000 0 200 400 600 800 1000 1200 1400 1600 1800 particules : elongated circle square 200x200 fraction 1% random spread Time (MCS) Grain area (sites) (b) Fig. 3.
Kinetic of grain growth corresponding to particle conditions of Fig. 4.

On the other hand, the number of the effective cutting-edges also can be identified based on the working surface, but, this method requires the determination of the typical grain shape.
From the experiment, it is confirmed that the grain shape should be almost spherical for making the numbers of the effective cutting-edge identified from the working and ground surfaces equal.
The grinding wheel WA60J7V, which has alumina grains of average grain diameter d0= 250 µm, is used.
(3) With considering the typical grain shape, the number of the effective cutting-edges can be also determined from the measurements of the working surface profile and the grinding force
(4) By assuming the grain shape as spherical, the number of the effective cutting-edge identified from the working surface topography well corresponds to that identified from the ground surface topography.

Table 1 ingredient of Al2O3 ceramic s [wt.％] Number Al2O3 Nb2O5 CAS 1 99.8 0.2 2 99.6 0.4 3 99.4 0.6 4 99.2 0.8 5 99.8 0.2 6 99.6 0.4 7 99.4 0.6 8 99.2 0.8 9 99.2 0.6 0.2 10 99.0 0.6 0.4 11 98.8 0.6 0.6 12 98.6 0.6 0.8 Detecting methods.
With the increase of CAS, plate grains appear, and columnar grain is obviously reduced (Fig.4c).
During the grain growing, Fig.8 is the growth model of columnar grain in manner of squeezed liquid phase.
Smaller grains attach to bigger ones via liquid diffusion, and liquid phase is pushed to the grain side, bonding bigger grains into columnar ones. 4.
Zhu: Transactions of Nonferrous Metals Society Vol, 18(2008), p. 388 a) Bamboo shape columnar grain; b) Squeezed liquid phase; c)Bonding and diffusion of grains; d) Columnar grain Fig.8 The grain growth model of a columnar grain b) c) d) 160nm a)