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By taking a closer look into the inner structure of the additive manufactured parts, as it is shown in Fig. 5, a fine-grained structure can be seen.
The mixture of fine-grained and martensitic structure of the additive manufactured cube indicates a higher hardness than measured in the solution annealed part.
The aim is to eliminate the flaws and to keep the number of the small pore by a minimum as they influence the fatigue strength of a forging tool.

Because the grain size depends upon the temperature strongly, it is believed that grain size of TiO2 particles in the dried gel should be smaller at 450℃.
Pollutants (P) under investigation serve here to reduce back the one electron deficient oxidized form of surface adsorbed MO+ to MO (Eq. 10) eCB-+O2→N-TiO2+O2-• (8) hVB++OH-→•OH (9) O2-•+eCB-+•OH→H2O (10) As seen from the above equations, it can be induced that hydroxyl groups played an important role in preventing the recombination of photogenerated electron and hole pairs, so the N doped TiO2 should produce a greater number of hydroxyl groups yield and a higher photocatalytic activity.

Further, the addition of Al2O3 particles to 6061Al matrix has led to decrease in grain size of the matrix clearly suggesting the heterogeneous action of the Al2O3 particles during solidification.
Further, as the amount of Al2O3p increases, the depth, width and number of grooves on the surface of the pin decreases, this results in increase of fatigue life as seen in Fig. 6(c-f).
Fig. 6b, 6d and 6f shows the presence of cracks in both matrix and composites and these cracks are originated at the grain boundaries of 6061Al matrix.

A non negligible number of large silicide particles with sizes up to (a) (b) (c) Fig. 1 – Microstructure of the as-atomized powder (45 µm – 75 µm blend): surface (a), cross-section (b, c).
The comparison of Fig. 3-a with Fig. 2-a shows that the microstructure has coarsened significantly with an increase of the grain size by a factor five to ten.
The microstructure is less homogeneous, with regions with either fine or coarser grain sizes (Fig. 5-a and -b).

From Fig. 3a, We can see some of the sprawling growth big grains.
It can be seen that a large number of hexagonal particles overlap each other and the particles are distributed evenly.
So, it can be seen that crystal grains grow with preferred orientation along the c-axis direction of hexagonal crystal system in the insert of Fig. 3b.

For example during DS there is an outflow of defects in the solid whether they are grain boundaries or dislocations or lattice defects.
The maximum amount of stored energy at defects and interfaces created in DS processing can be enabled by a high △μsl =(△Gsl/number of moles), wherever it happens in the solid–liquid region (s/l region) subject to second law restrictions on converting heat to work.
The kink in the PF curve indicates possible interaction between grain boundaries leading to a higher slope in the Sgen rate as a function of velocity.

Research on micro-arc oxidation coupled with electrophoretic deposition processing of HA/ TiO2 coating indicated that the number of HA particles integrated into the coating layer increased as the HA concentration increased [16] When plasma electrolytic oxidation was applied to ceria nanocomposite coating and ZrO2 nanoparticle on titanium substrate, it was reported that by increasing the concentration of nanoparticle the average size of surface roughness values was increased.
Chemical reactions are initiated next, and then nucleation and growth of the grains occur, resulting in the formation of dense particles.
Xu et al., Effect of oxidation time on cytocompatibility of ultrafine-grained pure Ti in micro-arc oxidation treatment, Surface and Coatings Technology. 342 (2018) 12–22

The interest in nanomaterials is nowadays great as the transition from coarse-grained to nanoscaled state leads to substantial changes in properties of the material.
The resulting material was a single-phase manganite powder with the crystal lattice of the orthorhombic modification and grains of 15-30 µm in size.
Note that the proportion of the specific surface area of powder particles measured by BET is close to this number (SN/SM = 5.9040 m2g -1 : 1.5722 m2g -1 = 3.75).

Fe-Ni based alloy powder was chosen as plasma cladding material, the grain size of which is 106-180 μm.
The oxide film hasn’t fall off during the isothermal oxidation which show that the heat stress is very little and grains of oxide bond well during the oxide growing.
For example, 1mol metal capacity is VM, the oxide capacity of 1mol metal generated is Vox, and the PBR is: (6) Among: M — oxide molecular weight; do — metal density; n — number of atom in oxide molecular; dox — oxide density; A — metal atomic weight.

It can be affirmed that the plasma spraying of an aqueous suspension P25 powder allows to obtain coatings where the anatase/rutile ratio and their average grains size are similar to that of the initial powder.
When the coating was elaborated from P25:EtOH:H2O suspension (reference E), the anatase ratio reaches 65.6% with an average grains size of about 30 nm.
FT-IR and XPS investigations showed that the photocatalytic performance of the aqueous suspension sprayed deposits could be attributed to a higher hydroxylation ratio of the coating surface, a lower waterweakly bonded content and the existence of a significant number of carbonate-based species on the coating surface [12].