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Therefore possible changes of the grain structure can be limited to the locally heated forming zone.
The disadvantages are the thermal strains, the oxidation of the surface and the potential influence of the grain structure.
In the practical tests the laser power amounts up to 1000 W, the dimension of the laser spot is 7.6 x 3.8 mm², the number of courses is 36, the scanning frequency is 11 Hz.

Also, it has been demonstrated that the oxidation and spallation resistance and the thermal insulation capability of such TBC can be improved with the increasing of number of layers of the bond coat.
The improved strength can be attributed to that the submirco-sized YAG particles can inhibit the grain growth of Al2O3 grains.

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.

Figure 2 displays the typical grain size distribution in six locations in Taichung.
Chang [3] obtained results for four locations; the cross symbol in Fig. 2 represents an average over three sets of grain size at the ICEC site; the diamond symbol plots an average over two sets at the anchor test site.
As shown in Table 1, the number of strands required for each anchor varied according to the dimensions of the anchor.

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).

Reduced grains size results in higher surface to volume ratio and the crystallites surface becomes a major factor influencing both processes.
We suggest that for lower concentration, Tb3+ ions are mainly located at the grain boundaries between crystallites of TiO2-rutile and the energy from excited nanocrystallites was intercepted by matrix surface states.
Acknowledgements This work was financed by the MNiSW in the years 2010 – 2012 as a supervisors research project number N N515 5242 38.

(2) In the equations: Px is the throughput of some aggregate (%) expected to calculate; I is the decline coefficient of passing percentage; d is a certain grain size of aggregate (mm) expected to calculate; D is maximum grain size of mineral mixture (mm).
Fig. 7 Suspended dense structure Fig. 8 Framework dense structure Fig. 9 Framework gap structure SISDG.According to the test results and the framework dense specimen, referring to a large number of practical experiences, the SISDG of CSM based on vibration method is put forward, which are summarized in Table 3.

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.