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A high-purity fine-grained SiC powder was used as the growth source.
Let the number of vacancies in the intermediate layer in the course of spinodal decomposition be .
If we assume that the decomposition yields 6H-regions and 3C-regions with widths and , we arrive to the vacancy number preservation condition with .

A key issue for the safety and reliability of those SRM missiles and consequently for the effective and economic managements of missiles' inventory is the efficient Structural Health Monitoring of the energetic propellant grain.
This elongation resulted in radius decrease with associated changes in waveguiding conditions for a number of guided modes in the fiber.
Acknowledgements This work was funded by the R&D Project SESAMO (SEnsors for StructurAl Monitoring) of the European Defense Agency, Grant Number A-0931-RT-GC.

However, in the conventional truing process, the diamond abrasives on the wheel surface will be dropped off by the diamond truer and the acting abrasive number on the wheel surface will be decreased.
In the conventional dressing process of the resinoid bonded diamond wheel, the abrasive on the wheel surface will be sharpened and the acting abrasive number will increase on the wheel surface by rubbing by the GC dresser.
Table 1 Grinding conditions Wheel Grain size Diameter Rotational speed Resinoid bonded diamond wheel SDC1200 Φ70 mm 12,000 min-1 Work piece Rotational speed Binderless tungsten carbide 500 min-1 Depth of cut 0.5 μm/pass Feed rate 0.5 mm/min Coolant Solution type 0.5 mm Approximate radius: 100 mm Φ50 mm 10mm Fig. 6 Geometry and view of Fresnel lens mold for structured grinding. 0 100 100 0 60 0 90 0 100 70 Bottom side surface Outer side surface Outer side surface Bottom side surface μm μm Fig. 7 Compare the diamond wheel edge of before truing and after truing.

The mean grain size of the alloy was about 18 μm.
Φ4Φ4 (a)Rotating bending (b)Ultrasonic Fig.1 Shape and dimensions of specimens Specimen surface Compound layer Specimen surface Compound layer Fig.2 Microstracture of nitrided alloy Specimen surface Compound layer Fig.3 S-N curves of plain specimen (a)Ultrasonic (b)Rotating bending Detail of notch 10 4 105 10 6 10 7 10 8 10 9 0 200 400 600 800 1000 1200 Stress amplitude a (MPa) Number of cycle to failure, Nf (cycle) Aged alloy-US Nitrided alloy-US Aged alloy-TC Nitrided alloy-TC 10 4 10 5 106 10 7 10 8 0 200 400 600 800 1000 1200 Stress amplitude a (MPa) Number of cycle to failure, Nf (cycle) Aged alloy-RB Nitrided alloy-RB Aged alloy-TC Nitrided alloy-TC Fig.6 shows relation between crack growth rate ddN and stress intensity factor range ΔK in both alloys under ultrasonic.

Finally, metal impurities in the grain boundaries can increase atomic activation energy and decrease diffusion coefficient of metal impurities.
When solidification interface shape is convex, the silicon ingot is easy to produce big air bubble and large numbers of defects.
When interface shape is concave, it is prone to form fine crystal zone and produce impurity entrainment, pore and large numbers of defects [9].

The theoretical studies show that the concentration of antisite defects on both the sublattices are comparable, but the number of vacancies on Nb sublattice is much higher than the number of vacancies on the Sn sublattice [11].
In general, vacancies are consumed by sites that act as sinks, such as interfaces, grain boundaries, and edge dislocations [14].

Comparing with the traditional rolling process of the strips, strips obtained by semi-solid rheocasting-rolling process have uniform microstructure, round and tiny grains, so it has a bright future in the processing of magnesium alloys [1,2].
Turbulent thermal conductivity and the thermal conductivity of the fine slurry compose the effective thermal conductivity ,which is expressed as follows: (2) Where λ- effective thermal conductivity coefficient, Pγ- Prandtl number, Cp- slurry heat capacity, K- turbulent fluctuation kinetic energy; ε- pulsating turbulent kinetic energy dissipation rate, λm- slurry thermal conductivity under the static state.
In this paper, the large number of latent heat released by the crystallization process are treated by the enthalpy method.

Deformation mainly occurres in newly formed ferrite grain.
is clearance time of pass number.
Acknowledgment Funded projects provided by State Key Laboratory (northeastern university), serial number:2009004.

The experimental results indicate that the average grain size of RE0.5Sr0.5CoO3-δ thin films ranges from 86 to 165 nm，and the film obtained by heat-treating at 750 °C is highly oriented <110>.
Because the amount and distribution of oxygen vacancy at interface region has a decisive influence on the electrical properties and stability of the SOFC, a number of studies have been focusing on the oxygen vacancy ordering and electrical transport property of La0.5Sr0.5CoO3-δ [7-10], There have few studies on the amount and distribution of oxygen vacancy at an interface region for RE0.5Sr0.5CoO3-δ (RE=La, Pr, Nd) thin films.
This plays an important role in enhancing the oxygen ionic transference number and ionic conductivity and in improving the performance of SOFC electrode.

Using an optical microscopy, Fig. 1 illustrates the microstructure of these three materials in which several twins and carbide were observed in the grain.
of cycles Inconel 600 (Plain Fatigue) Inconel 600 (Fretting Fatigue) Inconel 690 (Plain Fatigue) Inconel 690 (Fretting Fatigue) Incoloy 800 (Plain Fatigue) Incoloy 800 (Fretting Fatigue) 100 101 102 103 10 4 10 5 10 6 107 108 200 400 600 800 1000 1200 1400 1600 1800 2000 Friction force (N) Number of cycles INCONEL 600 (101MPa) INCONEL 600 (177MPa) INCONEL 600 (205MPa) INCONEL 690 (182MPa) INCONEL 690 (202MPa) INCONEL 690 (231MPa) INCOLOY 800 (150MPa) INCOLOY 800 (200MPa) INCOLOY 800 (230MPa) 10 0 10 1 10 2 10 3 10 4 10 5 10 6 10 7 10 8 0 5 10 15 20 25 30 35 40 45 50 Local relative slip amplitude (µm) Number of cycles INCONEL 600 (101MPa) INCONEL 600 (177MPa) INCONEL 600 (205MPa) INCONEL 690 (182MPa) INCONEL 690 (202MPa) INCONEL 690 (231MPa) INCOLOY 800 (150MPa) INCOLOY 800 (200MPa) INCOLOY 800 (230MPa) INCOLOY 800 used as steam generator tubes registered very low levels.
Fig. 4 illustrates changes in friction force according to the number of repetition cycles after applying a fretting fatigue test with 50MPa of constant contact force at the contact region between the specimen and the contact pad.
Fig. 5 shows the local relative slip amplitude according to the number of repetition cycles after apply a fretting fatigue test.
As shown in Fig. 8 (d), a large number of dimples were observed in the final fracture region.