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In Fig. 3, HRTEM image and diffraction pattern of the coating showed a typical of the amorphous structure embedding a number of nanocrystalline particles with a size of about 2 nm homogeneously.
Nanocrystalline TiAlCrAg coating had grain sizes about 200 nm.
Grain size reduction provided two contributions to the formation of an external Al2O3 scale [22]: (1) increasing the number of possible nucleation sites of Al2O3 due to an increased frequency of grain boundaries intersecting the alloy surface; and (2) enhancing the diffusivities of Al as a result of grain-boundary diffusion.
Therefore, the critical concentration of the nanocrystalline coating should smaller than that for a coarse-grain one.
Hence, grain size reduction enhanced the formation of a continuous Al2O3 scale and improved oxidation resistance, as observed at 900°C here.

The production of blisk type rotors by high temperature brazing of blades via powder solder as well as the production of blisks by friction welding have a number of design and technological difficulties dealing with joining of a number of close range positioned blades with a disc.
This is possible due to the fact that a specific feature of nickel is its high diffusion mobility, in particular, a high coefficient of grain boundary diffusion of nickel.
All these determine the necessity in ultrafine-grained or/and nanocrystalline structure processing of heat resistant deformed Ni-based alloys.
The uniform ultrafine-grained (UFG) microduplex structure (Fig.1 a) with γ grain size and δ phase plate thickness about 800 nm has been processed in alloy EK61 by multi-step isothermal forging.
It has been established that the structure with the grain size ~130μm (Fig. 1 c) is formed after annealing in one g - phase region up to 1215оС (6 h), air cooling and following ageing.

A parent austenite grain consists of several packets (the group of laths with the same habit plane).
When a grain boundary is being illuminated by the electron beam, diffraction patterns from grains with different orientations overlap in the Kikuchi pattern, so the IQ number is going to be low.
The IQ values were averaged over the scanned area, so we assigned one number to each surface.
This phenomenon comes from the fact that different areas have different surface morphologies and grain distribution.
Ginsztler, Evolution of special grain boundaries in austenitic steels, Materials Science Forum 589 (2008) 19-24

Introduction Transparent conducting oxides (TCOs) films are prerequisite for most photovoltaic applications and have been subjected to a very large number of investigations for several decades [1,2].
The morphology contains grain whose crystallite size is strongly dependent on the film thickness.
However, these grains have a large average size compare to that obtained by XRD analysis.
The resistivity of ZnO is directly related to the number of electrons, electrons formed by the ionization of the interstitial zinc atom and the oxygen vacancies.
And with the reduction in the density of grain boundary, the probability of impurity scattering at grain boundary decreases which lead to the arising of the Hall mobility.

The above results indicate that a higher spinning rate is always beneficial for enhancing the diffusion ability of hydrogen atoms in the alloys, for which the refined grain and the increased internal stress by melt spinning are mainly responsible due to diffusion coefficient be directly proportional to the internal strain [8].
Fig.5 shows the cycle number dependence of the discharge capacity of the alloys, at a charging-discharging current density of 20 mA/g.
The enhanced discharge capacity of the alloys is basically ascribed to the refinement of the grain and the formation of an amorphous phase due to the fact that the hydrides mainly exist in grain-boundary and amorphous phase regions [9].
The capacity retaining rates of the La0 and La2 alloys as a function of the cycle number are depicted in Fig.6.
The grain refinement produced by melt-spinning exerts a negligible effect on the anti-corrosion capability of the alloy, which is the major reason why Fig.6 Evolution of the capacity retaining rate of the alloys with cycle number: (a) La0 alloy, (b) La2 alloy the melt spinning nearly did not show a helpful impact on the cycle stability of the La0 alloy.

The level of information and required number of replications is illustrated in Figure 2.
In order to make inferences on member's properties, number of replications must be determined.
Knowing the expected variability and required risk of type one and type two errors, number of measurements can be estimated.
X-ray sensitivity and accuracy depends on the number of parameters associated with the emitter (x-rays source) and receiver.
A number of challenges need to be overcome before the technique can be effective in quantitative assessment.

These pores are formed by evaporation of excess water from fine-grained mortar containing lime sublime submicroscopic pores, but this technology is unfortunately dependent on the usage of expensive autoclaves in the production process [1].
This is a test of yield, density, foaming number and the half-life of the technical foam.
Foaming number This dimensionless number labelled as Nf expresses the ratio of the volume of technical foam formed from the given volume of foaming agent solution.
The technical foam of higher density, but a lower foaming number and a shorter half-life is created by aeration additives.
Then, after a number of experiments, we came to the conclusion that the optimal concentration is 2.5%.

Since then, although there have been inevitable peaks and troughs in the number of papers published, interest in the use of microwaves for processing ceramics has remained remarkably high.
To overcome this intrinsic processing difficulty, a number of 'solutions' have been investigated, such as: 1.
In addition, the combination of hybrid heating with a new firing strategy known as two stage sintering [16] has yielded the ability to achieve nanostructured zirconia with densities >99.5% of theoretical whilst retaining final average grain sizes as fine as just 65 nm using precursor nanopowders with an average grain size of ~16 nm [17], figure 3.
Provided sufficient migration across the bond line of both glassy phase and grains occurs, then a fully homogeneous microstructure can be obtained.
Known as IS (independent section) machines, they produce only one bottle at a time but are arranged in banks such that a large number (e.g. 20-50) bottles can be produced at the same instant.

And it’s characterized by a 2-3 grain size number (Fig. 1) according to the scale of macrostructures of titanium alloys [13].
Part of the boundaries of β-grains is bordered by a thin grain-boundary α-rim.
A different orientation of the colonies of the primary α-phase plates inside the grain is observed.
Typical grain (a) and intragranular (b) structure of VT23 tube The study of the structure by transmission electron microscopy is shown that the plates in the α-colonies do not contain a large number of dislocations (Fig. 3 a), but some of them are twinned and the twins break the plate into a series of parallel-oriented fragments (Fig. 3 b).
This provided the formation of a coarse-grained polyhedral recrystallized β-structure with a low dislocation density.

Effect of Cr content of grain boundary precipitates on creep-rupture property of heat-resistant steel Super304H Fig. 5 shows the variation of Cr content ((CCr)GBs) with count number frequency (R) of particles precipitated along grain boundaries in two groups of austenitic steel Super304H tube samples (WJ and SM) which experienced creep rupture tests at 700℃ and in a series of externally applied stress levels, respectively.
It is seen that the Cr concentration of grain boundary precipitate particles corresponding to a certain level of the R determined by the EPMA-EDS + MPSM increased with decreasing stress level and increasing creep-rupture time for the bulk steel samples.
The parameter Ka is defined as , showing the increased level of Cr partitioning in the grain boundary precipitate particles for a ruptured sample investigated.
This phenomenon indicates that the lower the stress level applied, the longer the rupture time experienced, and accordingly the higher the concentration in Cr in the grain boundary precipitates acquired in the ruptured samples, which reveals the fact that the Cr content of the grain boundary precipitates reflects directly their phase stability of the tube samples.
Fig. 1 Comparison of observed g¢ volume fractions [1-17] with those predicted by the present MPSM for some Ni-base superalloys Fig. 3 Comparison of observed g¢ lattice parameters [5,6,8,16,19-21] with those predicted by the present established calculation method for some Ni-base superalloys Fig. 5 Cr content ((CCr)GBs) vs. count number frequency (R) of grain boundary precipitate particles in two groups of creep-ruptured samples (SM and WJ) tested at 700℃ for Super304H Fig. 2 Comparison of observed TCP phase volume fractions [5] with those predicted by the present MPSM for some Ni-base superalloys Fig. 4 Evolution of the SRO parameters of Re in MC simulation Fig. 6 The externally applied stress level and Cr concentration distribution parameter Ka of grain boundary precipitate particles vs. creep rupture time in two groups of creep-ruptured samples (SM and WJ) tested at 700℃ for Super304H Table 1 g¢ volume fraction of