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Table 1: Space Groups, Atomic positions (Wyckoff positions), number of formula unit per unit cell (Z) in MgZn2 (C14) and MgCu2 (C15) types of structures.
Dark Region Bright Region Average Spectrum Element Weight % Atomic % Weight % Atomic % Weight % Atomic % Zr 3.57 2.01 57.79 42.59 25.87 16.12 Ti 17.94 19.19 21.68 30.43 18.52 21.98 Cr 7.20 7.10 2.21 2.86 5.49 6.00 V 71.28 71.70 17.99 23.74 50.12 55.91 Ni - - 0.34 0.38 - - Fig. 2: SEM microstructure of the bulk samples (a) Zr0.9Ti0.1Cr1.2V0.8 and (b) Zr0.9Ti0.1Cr0.8V0.8Ni0.4 SEM image of the Ni-doped sample (Fig. 2b) was used for further analysis by using the Scion software [12], in order to calculate the size of the grains of the microstructure.
The results are shown in Fig. 3, where it can be seen that most of the grains in the alloy had a surface area between 20 and 40 µm2.
Fig. 3: Surface size (grain size) distribution of Zr0.9Ti0.1Cr0.8V0.8Ni0.4 as calculated from SEM electron backscattering image.
The higher amount of hydrogen in the desorption curve (red) for Nifree sample is associated to the non-activated grains and should be activated more times for reaching the higher capacity. 0.4 0.5 0.6 0.7 0.8 0.9 1.0 1.1 1.2 1.3 1.4 1.5 1.6 -0.5 0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 Pressure (MPa) Hydrogen content (H/M) Zr0.9Ti0.1Cr1.2V0.8 Absorption Desorption 0.0 0.3 0.6 0.9 1.2 1.5 1.8 2.1 2.4 2.7 -0.5 0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 Hydrogen content (H/M) Pressure (MPa) Zr0.9Ti0.1Cr0.8V0.8Ni0.4 Absorption Desorption Fig. 4: Hydrogen charging and discharging of the compounds Zr0.9Ti0.1Cr1.2-xV0.8Nix (x=0, 0.4) at 30o C.

Figure 2 (d) is heat preservation after 2 h has not yet spread V8C7 grain area, it can be seen that the original reaction zone generated carbides reunite together, but can still see a small amount of carbide has been dispersed, granular.
Tab.2 The micro hardness value of each gradient layer measuring field Hadness number(HV0.05) Vanadium plate 408 V board and V2C junction 706 Measure once every other 20μm 2333→1339→680→595→536 from dense layer of V8C7 the junction of composites and matrix 386 Gray cast iron substrate 235 Fig.3 SEM of micro-hardness of different areas Fig.4 Microstructure of V8C7 particles scattered from Vanadium board center to joint zones layer(a) and the picture after wear(b) Figure 3 is from the heart of vanadium board to junction different gradient layer micro hardness indentation of SEM.
We can see, the V8C7 particles have dispersed, and grain is neat, no obvious phenomenon of reunion.    
Load effect makes the friction surface suffered from the longitudinal pressure, with the rotation of the tray, abrasive alumina has a plough cut on its soft substrates, produced furrows, when met V8C7 abrasive particles, due to the grain hardness is greater than the abrasive hardness, V8C7 particles will reduce Pierce the depth of the ferrite matrix and to prevent further plough of abrasive cutting function, we can also see from the figure that the furrows blocked by the particles.
Also we can see from the picture, the wear of composite layer surface still have few small cracks and the existence of the sticky pit, and a slight grain spalling phenomena.

A grain size distribution test of the soil was also performed to show the type and gradation of the soil.
The grain size distribution of the soil, which is used for the unfired soil lime bricks, spans from clay to medium grained sands. 60% of the soil, by mass, consists of fine to medium grained sands.
The same type of mixture and number of bricks was also employed for testing plain bricks (without any fiber addition).

Minimum allowance for the further mechanical treatment (about 200 μm), narrow heat-affected area (up to 100 μm), presence of fine-grained structure of built-up layer, minimum (local) energy deposition, increase of repair area of GTE blade surface, absence of heat treatment, higher mechanical characteristics of built-up layer refer to the characteristics of laser technology as opposed to argon-arc welding [8 - 15].
The structure of these blades is represented by columnar grains.
The microstructure of the samples is predominantly columnar grains, oriented along the direction of the temperature gradient according to the movements of the laser head (figure 2).
During the metallographic study of manufactured transverse and longitudinal sections, there are cracks that were found in a number of samples, located mainly along the grain boundaries of the cladded metal (figure 2b).

It can be found that the crystal face diffraction peak intensity increased with CeO2 doping amount increased comparing from the diffraction peak intensity, This is because that CeO2 can promote the growth of SnO2 crystal grain.
Grain is full and angular when the doping amount of CeO2 is 0.7wt.%, which shows that the crystal grows completely.
The reason is probably because that its main crystal had been changed, the diffraction peak become narrow and high, the crystal grain become big and complete.
Therefore, the adjacent oxygen vacancies increased when cerium ion replaced tin ion, which promoted the growth of tin dioxide lattice, but also generated a large number of electronic and increased the conductivity of SnO2 ceramic electrode [13,14].
This is because of the big grain granularity and high pore fraction.

The degree of cold plastic deformation by rolling the material to be hardened to a solid solution was kept constant at 50% in order to ensure consistency of the grain size and prevent anomalous grain growth during recrystallization.
The deeper into the base metal, the less consistent is the grain size.
Role of grain boundary ferrite layer in dynamic recrystallization of semi-solid processed type 304L austenitic stainless steel, Materials Letters. – V. 179. – 2016. – P. 65-68
Phys, 1983, number 1, pp 47-52

During welding boron diffuses and due to low solubility in austenite forms boridic particle in the grain boundaries region.
The knowledge of welding borated stainless steel is quite small in number.
The thickening of austenitic grain and boridic particles was observed in HAZ, thanks to welding thermal cycle.
The coarsening of austenitic grain and boridic particles can be observed in HAZ.
We can observe the presence of boridic eutectics in the grain boundaries after cooling.

Among these 7 boiler tube and pipe materials except GH2984 and Nimonic 263 all have got ASME Code numbers as shown in Tab.1.
Besides, there is also minor MC phase, including NbC and Ti(N,C) located inside the grains as well as at grain boundaries and having a size of 1-10μm and an amount of 0.52%.
HR6W characterizes with high content of W(7%W) to form Fe2W type Laves phase strengthening not only in grains but also at grain-boundaries.
Nimonic 263 contains with about 10% γ＇ and certain amount of M23C6 at grain boundaries.
Nimonic 80A characterizes with typical γ¢ strengthening in γ-matrix and M7C3+M23C6 Cr-rich carbides distributed at grain boundaries.

Also, the microsegregation of Mg and Si in the grains is high.
Simultaneously, the primary MgSi phases at the grain boundary are dissolved.
The small black dots in the grains are secondary MgSi phases.
They look like melted grain boundaries.
At the same time, the number of analysed pictures can be increased to get reliable results.

A notable aspect of the fine martensitic grain structure in the as-built structure is the presence of fine grains derived from the parent austenite grains, as depicted in Fig. 2(b).
Fig. 2(d) presents the corresponding EBSD grain orientation spread (GOS) map for the H13 TS in its as-built form.
The color-coded distribution reveals a varied grain structure.
Moreover, 42% of grains exhibit intermediate GOS values (2–5°, violet), which imply recovery or partial recrystallization.
Microstructure of the as-built AM H13 TS (a) EBSD phase map indicating the build direction (BD) and scanning direction (SD), (b) Grain size distribution map of the prior austenite grains corresponding to (a), (c) misorientation map of (a), (d) grain orientation spread (GOS) map Fig. 3 depicts the typical surface morphology of as-manufactured H13 TS produced through L-PBF.