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The crack growth increment for each cyclic loading (da/dN) in crystalline metals often occurs in the range of 10-6 to 10-3 mm, and this extension is usually smaller than the grain size of such materials.
Coarse grains were prepared by a strain-annealing technique.
The orientation of each of grain was determined by the back-reflection X-ray Laue method.
Fig. 2 Orientations of A-,B-,F-specimens. 450 400 350 300 250 200 150 105 106 107 108 Stress Amplitude(MPa) Number of cycles Non failure A-specimen B-specimen F-specimen 450 400 350 300 250 200 150 105 106 107 108 Stress Amplitude(MPa) Number of cycles Non failure A-specimen B-specimen F-specimen Non failure A-specimen B-specimen F-specimen Fig. 4 S-N curves of pure Ti single crystal, with different orientations. 100μμμμ m Crack growth direction [1120] [1100] [1120] [1120] [2110] [1210] Hole 100μμμμ m Crack growth direction [1120] [1100] [1120] [1120] [2110] [1210] 100μμμμ m100μμμμ m Crack growth direction [1120] [1100] [1120] [1100] [1120] [1120][1120] [2110] [1210] Hole were parallel to <11-20> (Fig5(a)).

The further investigation on corrosion interface (as shown in Fig.4 (b)) reveals that the preferential corrosion of the α-Fe occurs and then Zn atoms diffuses along the interface of Fe-Zn compound and grain boundary of α-Fe/Fe2B respectively.
Table 2 Average microanalysis results by EDS spectrum at each point in Fig.4 The main dissolution mechanisms between a solid and liquid metal corrosion can be described by various processes: dissolution, formation of intermetallic compounds at the interface, penetration of liquid metal along grain boundaries [12].
Nevertheless, a number of cracks occur under the phase transformation stress of corrosion products (shown in Fig.4 (c) and (d)).
Obviously, these cracks extend along the grain boundary from corrosion layer to substrate gradually (shown in Fig.4 (c)).
Number Fe Zn Phase wt.% at.% wt.% at.% 1 8.71 10.05 91.29 89.95 δ-FeZn10 2 6.79 7.86 93.21 92.14 ζ- FeZn13 3 0.00 0.00 100.00 100.00 η-Zn 4 11.31 12.99 88.69 87.01 δ-FeZn10 5 5.69 6.59 94.31 93.41 ζ- FeZn13 Conclusions The influence of boron concentration of cast high boron white cast iron on corrosion resistance to liquid zinc is investigated and the present work supports the following conclusions: 1.

Introduction Rice husk (RH) is the natural sheaths that form of the rice grains during their growth.
Due to the high silica content, rice husk has become a source for preparation of number of silicon compounds such as solar grade silicon [4], silicon carbide [5], silicon nitride [6], zeolite and concrete and cements surfactant [7].
Table1: The composition of the quartz replacement by RHA in weight percent Mix Number Kaolin Feldspar Quartz RHA AP1 50 25 25 0 AP2 50 25 20 5 AP3 50 25 15 10 AP4 50 25 10 15 AP5 50 25 5 20 AP6 50 25 0 25 The composition was mixed using a ball mill for 1.5 hours.
The solid grains rearrange and draw close to each other to form more homogeneous and continuous bulk, with a fine water absorption and the porosity decreases with soaking time.
The increase in the bulk density and the substantial decrease in porosity of the mixed containing RHA, are attributed to the glassy formation and densification of the individual grains during the vitrification process.

The number of composite nitride and carbon-nitrogen compounds correspondingly increases.
RE-iron inter-metallic brittle compounds formed within the grain boundary and grain interior when the RE contents is too high.
RE can purify the grain boundary and reduce the interface energy.
Table 6 gives the number of crack initiation in cycling process.
The samples without RE addtion had a number of thick crossing cracks.

As the result, Au nanoparticles are formed on the boundaries grains of the film of molten gold as shown in Fig. 1(a).
Melting at grain boundaries occurs due to a decrease in the melting point at the boundaries caused by a high concentration of point defects.
The particle size increases, and their number decreases.
The total number of particles also decreases.
Inset N is the total number of particles.

In China's coal mine, spontaneous combustion accounted for 56% of the total number of mine, the fires it caused account for 90% ~94%of the total number of mine fires [1].
Fig.2 and Fig. 3 for the coal fly ash and respectively of grain size of loess analysis results.
Fig.2 A coal fly ash grain size analysis Fig. 3 Loess some coal mine grain size analysis Taken from the fly ash and loess particle size analysis, the fly ash particle size is mainly concentrated in the 0-50μm; Loess particle size is mainly concentrated in the 0-60μm, solid particles larger than fly ash.

Among those methods, the Powder Metallurgy (P/M) route is generally preferred since it offers number of advantages.
After machining, the surface roughness values were measured in three different locations on the same slot using Mitutoyo surface roughness tester SJ-310 model with cut off length of (λc) 0.8 mm and number of sample as five using diamond tip of 5µm in diameter and is shown in Fig. 3.
The SiC particles in the Al matrix are non-uniform in size, irregularly shaped and randomly dispersed within the matrix grain as well as grain boundaries.
Microstructure images: (a) A356 alloy (b) MMC with 5% SiC A356 Alloy Al grain SiC 50µm MMC with 5% SiC SiC (c) 50µm MMC with 10% SiC (d) 50µm MMC with 15% SiC Fig. 4.

It was observed that although the coating was ~5 µm thick and continuous, the surface of the coating was rough. 0 10 20 30 40 0.1 1 10 100 1000 10000 Number (%) Diameter (nm) Size Distribution by Number Record 15: BaTiO3 29-03-2005 Figure 2.
As shown in Figs. 6 (A) and (B), even at 900ºC the particles sintered well and they even exhibited grain growth.
Since high surface area (i.e., fine grain size) and porosity are essential for sensing applications, sintering should be utilized for only achieving neck formation among particles to improve mechanical integrity of the coating.
In addition, grain growth should be prevented.

However, the as-deposited-CVD-film has a non-uniform thickness and grain size, randomly oriented crystals, and a high surface roughness with the mean surface roughness ranging generally from one to several microns [3].
A CVD diamond wafer as manufactured had a very coarse surface, whose initial surface roughness was 16 to 18 μm Ra, as shown in Fig.1(a), where the pyramidal grains could be clearly seen.
The Raman spectra collected from the surface have a sharp intense peak with positions varying from 1331.14 to 1333.12 cm-1, showing that these pyramidal grains were diamond [7].
This is because a Raman peak position will shift to lower wave numbers under tensile strains, but to higher wave numbers under compressive strains.

Rainwater especially in cities and towns with polluted air contains a great number of dissolved nutrients.
Pollen grains and the spores of microorganisms are released and then cling to frontages.
In the close nearness of a frontage (to 10 metres) grow birch trees and bushes in a small number, which probably serves as one of the sources of spores.
The plaster has very coarse-grained structure with sharp grains (Fig. 6), which is another positive factor for successful growth of microorganisms on the frontage.