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Due to the oriented grains of the cast carrots, only a few peaks were appeared in the bulk samples.
Table 1 shows the average size, number density and weight percent of the γ΄ precipitates under different cooling rates.
At higher cooling rates such as 15 ºC/min or air cooling, due to higher undercooling, an explosive nucleation has been occurred which has led to the higher number density as well as smaller precipitates.
According to Table 1, it is also observed that as the cooling rate is decreased, the size and weight percent of the γ΄ precipitates has increased as well as their number density has decreased.
The average size, number density and weight percent of the γ΄ precipitates under different cooling rates.

Such hypothesis is presented in Palmgren-Miner’s [1] model: , (1) where: D-damage degree, where a linear relationship is proposed, ni - number of loading cycles at a given stress level, Nfi - number of cycles to failure at a given stress level.
The model can be expanded to a chosen number of load block’s with the right modifications, e.g. for a three stage block loading program we obtain: . (5) · Chaboche and Lemaitre [5] model.
The authors have presented an exponential function in their past papers which distinguishes the load sequence [6, 7]: , (8) where: N – the current number of cycles to destruction at the instant t, Nf - is total number of cycles until failure.
Taking this into account by substituting equation (10) into equation (11a) and rewriting them in an integral form we obtain , (12) While solving the equation to obtain the constant λ we get: , (13) for - total number of cycles to failure we get: , (14) , . (15) The dependence between (16) and number of cycles N is shown in Fig.1 for φ=1 and λ=ln(2).
Eto, Effect of stress history on cumulative fatigue damage of fine-grained isotropic GCR graphite, Elsevier Science Ltd., Carbon Vol. 34, No. 8, 1996, pp. 967-974

Numerical modeling is useful to foundry engineers in knowing beforehand the condition of final cast product, in terms of controlling its mechanical properties, microstructural evolutions and grain morphologies, thus, improves the quality of casting.
A number of researchers in the past decades has provided a basic framework for solidification modeling, as indicated in the early work of Flemings and Nero [3] and Flemings et al [4].
Recently, macrosegregation in Al-4.5 pctCu in the presence of electromagnetic stirring was studied and reported by Poole et al [7], effect of frequency on segregation and final grain size was also reported.
They concluded that final grain size and operating frequency of the coil had the most significant effect on solute segregation.
Generally, the uneven distribution of the solute elements (macrosegregation) in casting system is as a result of 1. thermosolutal natural convection 2. shrinkage-driven flows 3. free floating grains and 4. deformation driven flows.

The chopping enhances the surface mobility of incident molecules and increases the number of nucleation sites which allows the adatoms more time to settle on the substrate.
This given extra time reduces grain size, fractures, voids, and vacancies in the films. 2 Materials and Methods 2.1 Thin film deposition and in-situ chopping of vapour Al2O3 thin films have tremendous potential for commercial application as anti-soiling and self-cleaning purposes of cover glasses.
Annihilation of excess vacancies dislocated grain boundaries, phase transformation precipitation or compositional changes produces additional strain in film and gives rise to intrinsic stress.
Due to the reduced grain size for WC films, the fractures are not propagating for long distance and it might be the one of the reasons for improved properties of EB evaporation coatings.
The SEM shows uniform surface morphology for films WC as compared to that of WoC which indicates a decrease in grain size in the films WC. 4 Conclusion Chopping of vapour atoms during deposition helps in extended time relaxation process to settle vapor atoms on the substrate and stress relief in the interfacial region, whereby the cluster formation is avoided and defect-free films are deposited.

Besides the methods of electromagnetic stirring, shear -cooling roll (SCR) and cooling sloop, scholars in China have also researched the methods of new strain-induded metal activation process [18], cooling slop tube [19], electricity impulse and quick-cooling [20], grain refinement and semi-solid remelting [21] and liquidus casting [22].
The essence of marking slurry (billet) includes grain refinement and spheroidization, especially grain refinement or dendritic breaking, no matter the methods of liquid or solid phase, which have been used to mark slurry (billet) of semi-solid state.
The paper [14] has reported that for in the process of spheroidization, increment in energy by methods such as stirring and grain breaking is helpful for formation of spheroidization. 3.2 Process stabilization of semi-solid die casting.
Literature [26], [37] and [38] have reported alternately semi-solid processing has been successfully applied to formation of many components such as connecting bar of automotive compression engine, automotive aluminum piston, wheel hub of automobile with XX model number.The most difficulty of industrial application is cost and quality.

According to guideline BS 1881: Part 201[1], non-destructive tests can be used in various situations, such as: technological control of preformed pieces; monitoring development of resistance; locating and identifying the extent of cracks, leaks and weak spots in concrete work; increasing the level of trustworthiness of a small number of destructive tests; evaluation of the potential durability of concrete; scheduling removal of molds and shoring; verifying fire damage; and follow-up of the effects of additives and additions.
High-initial strength and sulphate resistant Portland cement, potable water, natural washed sand (grain size 2.76, specific mass 2.59 kg m-3) and gneiss gravel (maximum typical dimension 12.5 mm. specific mass 2.63 kg m-3) was used to manufacture the assemblies.
This agrees with Mehta and Monteiro [2], which reports that in concretes with water-cement ratio around 0.55 the strength is lower by increases in aggregate grain size.
The vibration natural frequency of the compound seems not to be affected by the grain size of coarse gneiss (Fig. 2).
This means that thermography in the same way that the strength and the modulus is capable of detecting the nature and grain size of aggregates that were incorporated both in samples heated in the sun and were chilled Figures 6 and 7 show images obtained from two samples (with air incorporated and deterioration in a muffle furnace at 354°C for an hour) were cooled in the refrigerator or heated with solar radiation for two hours (from 2 to 4 pm).

These alloying elements are able to accumulate at the grain boundaries or to form the secondary phase particles, so that the galvanic corrosion in microscale is set up for the dissolution.
The reactions in the dissolution are expressed by Eqs. (1) and (2) as follow, where M is the dissolvable alloy matrix and x is the ionic charge number of the alloy matrix.
Meanwhile, they are able to penetrate the grain boundaries in the Al matrix, making these spots the most vulnerable under the stress.
Therefore, their grain sizes can be as big as 300 micron.
The highest cooling rate is at the periphery of the bar, and the heat in the center will be hard to dissipate out, leaving the bigger grain size at the center than those at the periphery.

Vacuum evaporation was a process which heated material by using vaporization and made the evaporated grain to spray on the substrate and formed solid film finally [6].
Open-circuit voltage was likely to the more recombination occurred in grain boundaries because of smaller grain size in low-temperature process compared with high-temperature process.
According to relevant research, incorporating a small number of sodium into CIGS thin film was contribute to improve its performance, thus, sodium was important to fabricate efficient CIGS thin film solar cells [15].
CIGS grain was smaller and the concentration of carrier was lower and there was high resistivity (In0.68Ga0.32)2Se3 phase in low temperature compared with in high temperature were discovered [17].

The grains, roughly round shaped, and grain agglomerates that dominate the microstructure, seem to be in a random orientation.
Typically, the conduction mechanism of metal semiconductor oxides is controlled by the amplitude of the potential barrier, which electronic superficial states due to chemical adsorption of oxygen species, for instance − 2O , induce in the grain surface and in the region between grains, an area depleted of electrons.
However it is perceptible when comparing the real part of the impedance plots at 40Hz, that, for the same working temperatures, when RH increases, impedance also increases (as the number of the physisorbed layers of water gets higher, for the same operating temperature, the complex impedance plot area increases instead of decreasing).

The key issue is the proper design of the W armour (size of tiles, grain orientation).
The selected grain orientation is parallel to the direction of the heat flow, in which case possible delamination is not so critical.
To ensure this function, the divertor components are subjected to numbers of non-destructive tests (NDTs) before the assembly and installation.
Divertor cassette size is based on the maximum size that can be handled via the Remote Handling (RH) ports and still have an integer number of cassettes per Vacuum Vessel sector.
To meet ITER requirements, numbers of NDTs at the various manufacturing stages of components are mandatory.