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However, high quality diamond coatings are difficult to achieve on these substrates for a number of reasons.
The bombardment of these particles on diamond grains may cause an ample enhancement of secondary nucleation.
The average grain size of NCD film was less than 50nm and the r.m.s. surface roughness of the smooth film was approximately 28nm.
A high nucleation density was initially obtained that could provide very large number of contact points with the Ti substrate.
The significant low COF is possibly attributable to: (1) The nano-crystalline grain size, which yields a very smooth surface and consequently a low COF; (2) A small fraction of amorphous carbon at the boundaries of diamond grains, which has a lubricating effect. 4.

Fig.1 was the grain cumulative grading curve of all samples.
In this test, five levels were divided to compact, and the compaction number at each layer was 151, the compaction work was 600kJ / m3 [6].
Compaction curves of grain cumulative grading before and after compaction were also shown in Fig.1.
The difference between Bg and B5 lies in the different statistical object: all the grain groups are investigated in Bg, and only coarse grain fractions are calculated in B5.
The table shows that both Bg and B5 are all increased with increasing of the initial content of coarse grain.

FeSEM microstructures show liquid phase assisted sintering leading to fused grains and exaggerated grain growth.
A good number of reports [3-5] are available on WO3-added BT4 since BaO–4TiO2–0.1WO3 system resulted in excellent microwave properties.
The FeSEM microstructures showed interesting flaky grain morphology, shown in Figure 2(a and b).
The low Qf might be due to this phase and also due to other solid solution phases along grain boundaries.
A good number of combination of dielectric properties suitable for application as patch antenna can be realized from this system.

Costa et al. (2002), given a one-dimensional discrete time series signal, the coarse-grained time series is constructed by averaging a successively increasing number of data points in non-overlapping windows.
The length of each coarse-grained time series is equal to the length of the original time series divided by.
After construction of the coarse-grained time series of a physiological signal, the SampEn is calculated for each of the coarse-grained time series, plotted as a function of the scale factor.
Note that for scale 1, the coarse-grained time series is simply the original time series.
If increasing the number of groups does not significantly improve the within-group and between group distances significantly, then the number of clustering groups should not be increased.

When the annealing temperature was at 730 degree, zonal structures in the steel substrate disappeared, but there were some un-equiaxed grains and some small grains, that meant the recrystallization was almost finished, but the grains grew not very well.
When the annealing temperature was at 760 degree, the grains were equiaxed and small grain numbers decreased, that meant recrystallization were finished completely.
Many small particles precipitated at 730 degree, and these particles distributed along with grain boundary and sub-grain boundary.
The grains were equiaxed and when the annealing temperature was above 760 degree, the grains hardly grew up
(3) When the annealing temperature increased, many small particles precipitated, and these particles distributed along with grain boundary and sub grain boundary.

The grain sizes of resin bond diamond abrasion wheel are #270, W10 and W5.
Intracrystalline grains of ZrO2 is combined with alumina matrix directly and not incorporated into other impurities.
As shown in Fig. 3, the large numbers of dislocations are formed due to local residual stress in ZrO2 crystal lattice.
Under ultrasonic vibration, Less integrated grains are formed and the cracks appear on them.
The results show that ZrO2 plays an important influence on the generation and expansion of cracks and enhances the strength of grain boundaries.

Although there have been a large number of investigations on LCF property of Udimet720Li alloy, a systematic investigation on LCF property for PM Udimet720Li alloy is very few.
Before LCF tests, the grain morphology of the PM superalloy FGH720Li was observed by OM (Fig. 3a), the grain size was uniform and fine, there was no abnormal grain in the alloy, and the average grain size was about 10 μm.
Since the solution temperature was lower than the solvus-temperature there was a large number of primary γ’ precipitate located at the grain boundaries, and the distribution of primary was uniform in the alloy.
Fig. 3 Microstructure of FGH720Li alloy (a)grain morphology, (b)distribution of γ’ phase.
There were a large number of secondary γ’ precipitates with the size of between 100 nm and 200 nm, and the tertiary γ’ precipitates with the size lower than 30 nm.

Figure 4 summarizes the counted number of voids over the size of about 1µm in the area of 400µm x 500µm around central region of the minimum cross section.
In both type of specimens, large number of voids are nucleated after large scale straining just before ductile cracking, whereas no remarkable increase of voids can be seen before such large straining.
Fig. 4 Evolution of number of voids observed around center of minimum cross-section.
Table 3 Comparison between average dimple size and average grain size after straining.
Fig. 7 Comparison between fracture surface appearance and deformed grains for both smooth and R2 specimens.

Pulse frequency and pulse number are 3 ~ 20 Hz and 5000, respectively.
The effect of the grain size on hardness has been studied and explained by some authors.
Grain boundary hardening and grain boundary sliding are two mechanisms of the possibilities to change the hardness of films [13, 14].
According to the Hall–Petch relationship, the hardness of materials increases with decreasing grain size.
On the other hand, softening of materials caused by grain boundary sliding is mainly attributed to the large amount of defects in the grain boundaries.

Both properties allow us a number of new innovative investigations which have been discussed elsewhere [1,2,3].
The number of exposures depends strongly on the texture itself.
A medium grained Ti 2.5 Cu was heated up till 875°C in steps of 25°C using a mirror furnace originally used for neutron diffraction.
Grain growth started explosively at 875°C so that only some large β-grains existed.
Acknowledgments This work has been funded by the German Ministry of Education and Research (BMBF) under the contract numbers 03BRE8CL and 05KS1MCA/2.