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The grain size was 1-4µm.
When the substrate temperature was 600°C, the sheet had sharp irregular polyhedral grain, and when the substrate temperature was 700°C the sheet had quite regular grains.
The grains are with sharp irregular polyhedral shape.
As the number of turns of the substrate is 12 round/min, the upward vertical acceleration introduced by bonding force or adsorption affinity is calculated to be 8.5m/s-2.
The grain size is 1-4µm.

The effective strain gradient increases with the number of compression.
Introduction The reduction of average grain size to an ultrafine grain scale represents a traditional way of improving mechanical properties of polycrystalline metals and alloys.
The number of initial tetrahedral elements was 30000.
Moreover, the strain gradient increases with the number of CCDC.
The strain gradient increases with the number of CCDC by two routes

AFM analysis presented different morphologies, showing that the coatings with 15 bilayers had an average grain size of 49 nm; while the 30-bilayer coating exhibited grain sizes of 99 nm.
This is due to the increase in number of bilayers with nanometric thicknesses, which, along with the applied voltage polarization, present a variation in the microstructure - evident in the reduction of grain size.
Grain size and roughness results are shown in Table 1.
Bilayer Grain size (nm) Roughness (nm) 1 113 ± 9 4.4 ± 0.5 8 39 ± 4 3.6 ± 0.5 15 49 ± 4 3.2 ± 0.5 30 99 ± 6 1.9 ± 0.5 The graph on roughness versus the number of bilayers is observed in Figure 2.
Vol 24, number 8, (1953), p 981-988

The rapid improvement of fracture strength probably due to the decrease of grain size, pore distribute and the second phase (redundant Si4+ ions) segregating on the grain boundary which enhanced the bond energy of grain boundary.
The addition of SiO2 has significantly effect on grain size.
The increasing of the addition of SiO2 reduced the average grain size which cause the grain boundary phase increased.
Furthermore, the number and distribution of pore in the specimens reduced also enhance the bond energy of grain boundary and result the fracture mode to predominantly transgranular.
Acknowledgements The authors gratefully acknowledge the support of the National High Technology Research and Development Program of China (grant number: 2001AA325030).

The power of grain size was taken from a regression model developed previously that is able to predict the static recrystallisation kinetics of vast number of carbon and microalloyed steel grades.
It was reported that due to the pinning effect exerted by sulphur-rich particles, grain growth is delayed up to reheating temperatures as high as 1250°C, thus resulting in a fine austenite grain size prior to subsequent deformation.
No specific study was undertaken to vary the grain size and to estimate the grain size exponent (s) for two reasons: first, it is quite difficult to get large variations in grain size owing to the presence of sulphide inclusions, which retard the grain growth process up to at least 1250°C [2] and secondly, the grain size exponent has also been found to be strongly grain size dependent [8-10].
Hence, the equation developed for the grain size exponent (s) in the previous regression model [8-10] has been employed here in predicting the SRX kinetics.
Similarly, systematic relaxation tests carried out on a number of C/CMn steels yielded strain rate exponent values in the range -0.75 to -0.8.

The average WC grain diameter was approximately 0.45μm.
So, the aggregate of several WC grains or coarse WC grain with sizes of 6 – 7 mm in diameter become the fatigue crack initiation site for the present fine grained WC-Co material.
Figure 6 shows the variation of crack lengths, 2a as a function of number of cycles, N.
(2) The aggregate of several WC grains or coarse WC grain with sizes of 6 - 7 mm in diameter become the fatigue crack initiation sites for the present fine grained WC-Co material.
(3) The fatigue lifetime can be approximated by the crack propagation life, and the number of cycles spent in crack initiation can be neglected

This will allow to save metal, reduce the required deformation force, costs of labour and energy due to reduced number of passes of the metal through the working stands.
That is, the use of this tool provides a fine-grained isotropic structure in the volume of deformed metal.
The maximum difference in the number of slip lines when comparing longitudinal and transverse cross sections is observed after rolling of brass billets in smooth rolls (fig. 5).
Visually, this is reflected in the fact that within some grains of the glide lines of dislocations more than the other (fig. 5 a,b).
After rolling in the relief rolls, this is not observed, the distribution of slip lines within individual grains and in the other direction is uniform (fig. 5 c,d), i.e. all the grain in a relatively equally involved in the gliding of the dislocations, and, consequently, in the plastic deformation.

It is indicated that the average Nusselt number showing an undershoot during the transient period and that the time needed to reach the steady state is longer for low Rayleigh number and shorter for high Rayleigh number.
This interest was estimated due to many applications in, for example, packed sphere beds, high performance insulation for buildings, chemical catalytic reactors, grain storage and such geophysical problems as frost heave.
Variation of the transient average Nusselt number with s at different Rayleigh number.
This variation of the transient local Nusselt number is reflected on the average Nusselt number.
Fig. 4 shows the variation of the average Nusselt number with the dimensionless time for different Rayleigh numbers.

However, the addition of Ce increased the proportion of high-angle grain boundary from 33.2% to 40.2%.
A large number of studies[1-4] have shown that adding appropriate amount of rare earth in steel can improve the welding performance, mechanical processing performance and mechanical properties of the material by refining the grain, metamorphic inclusion and microalloying.
In the boundary maps of the 1# (Figure 3c) and 2# (Figure 3d) steels, the blue and red lines respectively denote the low-angle grain boundaries (5°＜θ＜15°) and high-angle grain boundaries (θ＞15°).
The HAGBs can change the crack propagation direction or interrupt the crack, hinder the crack propagation effectively, facilitate grain boundary sliding and enhanced grain rotation, which improve the ductility of the material [6].
(b) (a) Low-angle grain boundary (5°<θ<15°) High-angle grain boundary (θ>15°) (c) (d) (f) (e) Figure 3.

Chromium diffusion along the grain boundaries is more favorable.
The carbide formation reveals that the distance between carbides increases and the number of grains in the steel decreases as carbides grow.
Fujibayashi et al. also observed cavities with dimensions of less than 5 µm in small grains [5].
This progression can happen either inside the grains or at the grain boundaries, depending on the microstructure and stress state of the material.
In this study, Fig. 5b confirmed that cavities located near grain boundaries were due to high load, under which, the stress concentrated on the grain boundaries, leading to the formation of cavities near these positions.