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The Al5Fe2 phase consisted of columnar grains having a {001}-fiber texture.
The lack of bulk material has limited the number of studies on the properties of iron aluminides.
The columnar Al5Fe2 grains possess a pronounced {001} fiber texture (Fig. 3(b),(c)).
This reflects the anisotropic diffusion processes in the [001] direction in the columnar grains in accordance with its anisotropic crystal structure [13].
Additionally, the location of Fe, which remained far behind the maximum growth front of the fringy Al5Fe2 layer in between the columnar Al5Fe2 grains (Fig. 2 and 3), indicates qualitatively that Al is the dominantly mobile species as without DC application [9], albeit it diffuses faster.

The thickness of the ZnO film was varied by changing the number of coatings from 2 to 12.
We also note that the shoulder height decreases with the number of ZnO coatings increase.
Soleimanpour et al reported that when the thickness of film increased the grain size also increased and film coverage improved which caused a higher dispersion of the incident light [30] .
The obtained ZnO gap value is about 3.2 eV and does not practically change with the number of ZnO coatings number increasing.
We can observe that the degradation rate increases with ZnO coatings number increase from 2 to 6, and then it decreases when the number of ZnO coatings increases from 6 to 12.

Surface roughness depends on the thin film grain size which in turn depends on the cluster nucleation density [3], therefore SiC film quality can be controlled via managing nucleation process of SiC clusters on the Si surface.
Each process k (k = 1..n, where n is the total number of possible processes) is determined by the probability of realization of this process per unit time and occurs with rate Rk (s-1).
The activation energy for C atom diffusion depends on its local environment and can be represented as follows: Ed = Em + ΣlbEb + ΣliEi, (4) where Em is the migration energy for the carbon adatom, lb, li are the numbers of the nearest carbon and impurity atoms respectively and Eb, Ei are the bonding energy between C and Si atoms in SiC and between C and impurity atoms respectively.
The second term in the right side of the expression (4) takes into account that the bonding energy between Si and C atoms in the SiC cluster on the Si surface depends on the total number of the SiC molecules and hence the number of C atoms in the cluster.
In case of cluster edge diffusion of the carbon atom, i.e. the total number of the neighbors before and after the hop is the same, the edge diffusion rate R3 is equal to: R3 = υ∙exp(-Em /kbT)

And Nf is the number of cycles to failure.
Glossy spots are seen on the fracture surfaces in both environments, though the number of glossy spots increases in hydrogen.
Furthermore, though Nf in hydrogen is less than that in nitrogen, the number of such grains with developed slip bands as indicated by arrows in Fig.6 in hydrogen is more than that in nitrogen.
Number of cycles to failure Total strain range ∆εt [ ]% → → → in air in H gas2 10 4 10 5 10 6 10 7 0.3 0.4 0.5 0.6 0.7 0.8 Fig. 1 ∆εt-Nf curve (a) in air enlargement of (A) (a) (b) (b) in hydrogen Fig. 3 Flat site on the fracture surface in hydrogen Fig. 2 Fracture Surfaces (a) (b) enlargement of (A) (c) enlargement of (B) in air (∆εt =0.57%, Nf=74500) (d) (e) enlargement of (D) (f) enlargement of (E) in
hydrogen (∆εt =0.56%, Nf=204000) Fig. 4 Ductile fracture surfaces in air and in hydrogen #2000 finished (A) L=0.1mm 0 50000 100000 150000 200000 0.1 1.0 10.0 in Air in H2 gas -1 Number of cycles N Crack length l [mm] in H2 gas -2 in N2 gas Loading axis Fig. 5 Crack growth plots.

The average area, average diameter, total number of cavities and surface roughness of sealed film are shown in Table 1.
The average area, maximal diameter and total number of cavities for boiling water sealing films is the biggest and these for sol is the smallest.
The average area, average diameter and total numbers of cavities in films sealed by Na2Cr2O7 and boiling water are bigger than unsealed films.
The total number of cavities for boiling water is most in per square millimetre, and it is least for sol sealing.
(2) Two-dimensional morphology shows: the surface of unsealed films consist of rounded grains, the one by sol have some raised bulk and the ones by sodium dichromate and boiling water appears round or oblong cavities

However it does not implement the photolithograph process in the fabrication of pattern-less nanotubes but it needs to control the grain size of the metal catalyst to complete the fabrication of high density grown nanotubes.
Fig. 1 Illustration of CNT pattern Size Measurement Procedures Seven carbon nanotubes samples are used in the measurement tests; in which numbers 1–3 are high density pattern-less carbon nanotubes; their grown heights are 64µm, 80µm and 100µm respectively.
In Fig. 5, it is the spectral analyzer measurement result for the number 2 CNT (pattern-less CNT with 80µm height) while in Fig. 6, it is the spectral analysis result from the mirror-formed reflector.
From Fig. 5, it observes that when number 2 CNT is implemented as a reflector its reflected optical energy is quite small and it also suffers large noise interference.
The measurement results for numbers 1–3 CNTs are tabulated in Table 1, it shows that with grown heights of 64.3 um, 79.4 um and 96.8 um pattern-less CNTs they have the same return loss of 45 dB and this is equivalent to a reflectivity of 0.56%.

As a result, it was shown that introducing Si improves the strength of the interface (and the composite material in general) for different grain orientations.
Extensive studies were carried out on the sliding at metal/metal interfaces with same material (grain boundary) in Al [6, 7], Cu [8] and Ni [9] or different materials of Ni/Zr [10], Ta/Al, Cu/Ag [11].
The critical shear stress (CSS) was calculated based on applied force (fi) and number of atoms in moving zone (N) and the cross-sectional area of a layer (S) (Eq. 1). ⋅= ∑=S f N i i 1τ (1) The threshold of applied forces for initiating sliding at the interface was determined for various Al/Si interfaces with different alignments and orientations.
However, the applying shear force causes inter-granular sliding between two mis-oriented Al grains, without any distortion of the lattice at the Al/Al interface nor inside the Al.
Number of non-three-atom rings in Al before and after sliding for 5, 10, 15, 20 and 25 ps, 10 Å regions near the interface was considered. 0 1 2 3 4 5 6 7 1 2 3 4 5 6 Region_1 Region_2 Region_3 Displacement (Å) Time (ps) a) 0 0.2 0.4 0.6 0.8 1 1.2 1 2 3 4 5 6 Region_1 Region_2 Region_3 Displacement (Å) Time (ps) b) Figure 5.

Powder metallurgy (P/M) of Ti-based alloys may lead to the obtainment of components having weak-to-absent textures, uniform grain structure and higher homogeneity compared with conventional wrought products.
For fine-grained binary TiAl alloys, the room temperature elongation to fracture varies with Al-content, exhibiting a maximum at the two-phase composition Ti–48Al [3-4].
Microstructural varieties numbered 1 to 5 represent regions where EDS analyses were performed (Table II).
This structure is characterized by the presence of γ grains and lamellar colonies of alternating layers of γ and α2 phases.
(d) A duplex microstructure was obtained by hot pressing route characterized by the presence of γ grains and lamellar colonies of alternating layers of γ and α2 phases, where a high densification could be reached.

A higher number of S phases appeared in low-Zn/Mg ratio alloy during homogenization treatment compared with mid-Zn/Mg ratio alloy with a regime of 465°C/24h.
Alloy number Wt. % At. % Zn Mg Cu Zr Fe Si Al Zn+Mg Zn/Mg A1 7.27 1.82 2.04 0.1 ＜0.01 ＜0.005 Bal. 6.3 1.5 A2 7.78 1.61 2.02 0.1 ＜0.01 ＜0.005 Bal. 6.3 1.7 A3 8.03 1.42 1.94 0.1 ＜0.01 ＜0.005 Bal. 6.3 2.0 Results and Discussion Microstructure and DSC analysis of as-cast Al-Zn-Mg-Cu alloys The microstructure of three as-cast alloys under optical microscope (OM) are shown in Fig. 1.
Plenty of heterogeneous MgZn2 precipitates formed during the cooling of the ingots were observed around the grain boundaries [17].
In fact, the MgZn2 phase formed by Zn and Mg elements is only precipitated near the grain boundary, and its content is very small.

After annealing at 600°С, a recrystallized structure starts to form; i. e., separate recrystallized grains with a size of 10–20 μm appear within the initial grains and along their boundaries (Fig. 19d, e).
Inside the β-phase grains, individual crystals of α-phase or their groups are observed.
The smaller structural elements inside these “traces” are the really grown recrystallized grains.
Number of cycles to failure was about 8800 for Ti-Nb-Ta and about 3300 for Ti-Nb-Zr alloy at 1.0% strain (approx. 780 MPa).
Zhu, Corrosion resistance of ultra fine-grained Ti, Scripta Mater. 51 (2004) 225-229