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In addition, the grain size of thin films was extracted from the XRD data by a standard methodology.
When sputtering temperature and sputtering power is fixed, the content of the nitrogen in the cavity is low at a lower N2/Ar flow ratio, the number of nitrogen atoms is far less than the number of the sputtering out of copper atoms.
Table 1 Effect of N2/ N2+Ar ratio on the FWHM and grain size of Cu3N (100) Sample No.
As we all known, the grain size mainly depended on the competition of the growth speed between growth and nucleation.
The FWHM of peak (100) is 0.758, corresponding grain dimension of 10nm.

It is seen that grains with light contrast develop, particularly in the outer regions, of the coating and that the size and relative fraction of these bright grains increases with time.
The reduction in number of precipitates can be readily associated with the development of γ' grains within the coating since Re, Cr and W are soluble in γ' whilst only Cr is readily soluble in βNiAl [17, 20].
The ripening and rearrangement of refractory metal sigma phase precipitates also involves diffusion of Re, Cr and W through the coating to either γ' grains or preferentially to grain boundary sites where they would be expected to be more stable.
A Pt modified β-NiAl coating on CMSX-4 alloy undergoes transformation to a mixed βNiAl + γ'-Ni3Al coating with solution of certain refractory metals in the γ' grains. 2.
Both Ostwald ripening and rearrangement effects arise for refractory element precipitates in the coating such that the number of precipitates decreases, their size increases and they predominantly partition to grain boundaries in the coating. 4.

Due to the large grains size of the parent b phase, the specimen was rotated in order to increase the number of analysed grains, limit any texture effect, and obtain the amount of each phase.
Using a heating rate of 0.14°C/s (fig. 4a), very small quasi equiaxed grains are obtained, distributed homogeneously in the grain.
Precipitation along grain boundaries of the parent b phase can be noticed too, surrounded by a precipitate free zone.
The high number of particles also limits and hinders the growth of the new phase.
The primary a grains have not been modified but we can observe that a secondary phase has precipitated between these grains showing a dense and fine acicular morphology.

In-situ formation of elongated β' grains have been shown to increase the toughness of the material.
The idea was to prepare a single phase so-called SiAlON ceramic without an amorphous grain boundary.
Although a number of cations can stabilize the α-structure, extensive phase relation and properties studies have previously mainly been carried out in the yttrium containing system [9-12].
The bridging of cracks by intact elongated grains and grain pull-out are observed in the region behind the crack tips, just as with whisker reinforced ceramics.
This behaviour led to a number of impact studies at high strain rates (103 and above) and the shock physics and chemistry Fig. 6: Comparison of flexural strengths (average of 4 samples) of different non-oxide materials at high temperatures - Al2O3-TiN, RBSN and AlN [Ref.31].

The value and distribute of the measured flume and river sediment date 1~0.99 0.99~0.9 0.9~0.8 0.8~0.7 0.7~0.6 0.6~0.5 <0.5 Number 7843 379 148 145 118 29 2 Proportion 90.52% 4.37% 1.71% 1.64% 1.33% 0.33% 0.02% Eq.5 can be simplified as （6） The common methods to express in Eq.6 are in Table2 Table2.
When the grain is relatively small()，the critical start velocity in Eq.8 can be neglected, so Eq.8 can be defined as （9） Now Eq.9 is very similar to Velikanov Equation and some other open channel equation of sediment carrying capacity, which is also proved the rationality of the formula.
In rivers with comparatively larger grain, is more reflected the power factor of flow sediment. while in inshore with comparatively small grain, when diameter of the grain is less than 0.03mm,we use flocculation settling velocity of 0.03mm to replace of the grain settling velocity.
In order to consider the gravity effect of comparatively larger grain, is used to revise Eq.10 as （11） Where is a parameter, and are special form of Eq.11.

In order to prevent the fatigue crack propagation that was verified in service [3], a recently developed ultrahigh-strength austenitic stainless steel was selected (Cr-Mn steel - number 1.4376) and its mechanical properties and the fatigue resistance are under study.
While offering a good corrosion resistance, these alloys when welded or cooled slowly from high temperatures, may become susceptible to intergranular corrosion by the precipitation of chromium carbides in grain boundaries [4].
Inclusion of MnS Inclusion of TiO Before the chemical attack was applied, both steels were observed in the microscope, having been detected some inclusions (Fig. 2a, b); after 15s of chemical attack, the observation of the microstructure have shown carbide precipitation, in both steels, at the grain boundaries (Fig.2c), as well as ferritic phase (Fig. 2d).
The ASTM grain size number of the AISI 316L and Cr-Mn were determined through a grain size scale applied in the microscope, having been reached a value of 3 and 8, respectively, corresponding to a mean diameter, d, of 12,7µm and 2,25 µm.
[ ]MPa d �AlTi�b WVMo CrSiC         ++++++ ++++++ = − 21 %2,0 46,016,03282,07,16,2 29,02,194,024,03,1234,4 4,15 δ σ (4) [ ]MPa t Al Ti�bMo�iSi�C rot         +++ +++++++ = − 21 82,014,02,1 0,30,52,111,04,2553529 4,15 δ σ (5) where, δ, is the percentage of ferrite (Table 2), "d", is the mean diameter grain size in [mm] and "t" is the macle's distance (twin martesitic grains) in [mm], which for the Cr-Mn steel was approximately equal to 0.005mm (Fig. 2f) and 0.090mm for the AISI 316L (Fig. 2e).

In experiments carried out in the current research number of cycles to failure of multilayer materials was higher than those for bulk materials.
Traditional ways to increase individual properties of metals and alloys are work hardening, grain size refinement, fine precipitates distribution in the matrix and solid-solution strengthening [1].
Despite the fact that the technological aspects of such materials obtaining are described in number of papers [2,3,4], the structure and response of multilayered materials to static, dynamic and fatigue loads still remains uninvestigated.
It should be noted that the average size of recrystallized ferrite grains is 100…400 nm.
The graphs in Fig. 6a allows us to conclude that the number of cycles to failure in a multilayer composition is slightly higher compared to bulk samples.

The results show that Al content has an effect on the morphology and grain distribution.
The images show the co-existence of small and relatively large grains on the film surface.
And the small grains were granular while large grains presented a flaky texture.
The proportion of large grains become increase as the atomic percentage of Al increases.
Furthermore, it also very likely, the resistivity increased due to the emergence of large number of flaky substance which had a larger interval than the packed small grains.

Combined with desulfurization activity experiment, it can be inferred that the breakthrough time of nano-copper oxide with grain size of 24.3 nm is 20 min, which is much shorter than that of 235 min with grain size of 19.0 nm.
So the big grain size of nano-copper oxide is not in favor of H2S adsorption.
The diffraction peaks at 2θ = 35.5 °, 38.6 °are weak, indicating that the sample contains copper oxide and grain size is small.
But a number of other diffraction peaks, which appear in the figure, seem to be the diffraction peak of Cu(OH)2 compared with the standard spectra.
(2) XRD analysis shows that nano-copper oxide prepared by hydrothermal method has larger grain size of 24.3 nm.

The microstructures and grain sizes of GNS/ Al2O3 composite powders have been investigated.
The reduction of graphene derivatives stands out as the primary strategy that can yield bulk amounts of graphene like sheets, but certain sorts of functional groups are difficult to remove by reduction, leaving a significant number of defects.
The SEM image of initial Al2O3 powders without any treatment shows that the grains tend to agglomerate into larger particles (Fig. 1a).
In our method, the structure of Al2O3 grain was entirely not destroyed, and the grain sizes decreases to a certain extent during the milling process (Fig.1e-f).
This suggests the grains of initial Al2O3 are relatively coarse and the crystal is relative complete.