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Inter-pass temperature as a function of layer number for the 6 studied specimens Geometrical outcomes As previously discussed, the aspect ratio HW helps visualize the flare effect on the walls.
With t0 condition (Fig. 5(b)), the grain orientation changes from vertical to pointing toward the center of the last deposited bead.
EBSD measurements have also shown that heat accumulation leads to larger columnar δ-ferrite grains (coarser grains), and the use of the aerosol leads to a refinement of these grains.
Heat accumulation significantly decreases the ferrite fraction, coarsens the grains, and reduces the hardness of the produced parts.
Further investigations are in progress to examine the effect of grain size on the resulting microhardness.

During the sintering process, the corundum grain fineness has a significant influence on sintering density.
So the rapid grain growth is partly controlled and the sinter mechanical properties is improved.
Therefore, though high content of spinel generated can refine the grain, bad grain boundary diffusion may occur and result in bad effect on sintering densification.
According to this equation, if the grain sizes remain unchanged, flexual strength will decrease as porosity increases.
This results mainly from large number of glass phase and second needle-like mullite generation during the sintering process.

So a large number of publications on many different TiaVbCrg compositions can be found devoted to the analyses of hydrogen absorption/desorption characteristics.
For the (TiCr1.8)80V20 the grain boundaries are clearly visible as Ti-enriched (remains of a TiCr2-type phase seen by XRD) as shown Fig. 2a.
The H-permeation leads to the formation of cracks along the grain boundaries and exposes new surfaces to hydrogen that can penetrate within the b.c.c. grains.
Alternative situations must be considered, as for example a Ti-rich layer formed around the grains.
No direct evidence was found to indicate that the high Ti-content layer formed as a grain/boundary interface was indicative of the overall hydrogenation kinetics.

The other type of copper oxide (CuO) is a typical p-type semiconductor with a number of qualities noteworthy, including the capabilities of the optoelectronic, the activity of the catalytic, accessibility, the high value of the stability, and the activity of the antibacterial.
At the lowest laser energy, the samples have a rough surface and uneven grain size; however, when the laser energy is increased to 1000 mJ, the grain distribution becomes more uniform, with no change in the morphological features, figures (2a) and (2b) depict this, respectively.
It has a homogeneous compact and dense surface, with noticeable grain size decrease as the laser energy of 1200 mJ is increased.
Individual vertical grains have grown vertically, demonstrating that the grains are equally dispersed over the scanned area of 5 μm2.
As the laser energy increase from 800 mJ to 1200 mJ, the average grain size decreases from 92nm to 69nm.

Table 1: Main experimental parameters Specimen number Peak current [KA] Discharge capacitance [μF] Pulse frequency [Hz] Single pulse energy [J] Current density [KA/cm2] 1 0 0 0 0 0 2 12.98 120 1 1.35 33.714 3 25.66 120 1 5.4 66.649 4 52.02 120 1 21.6 135.128 Fig.1: Schematic diagram of experimental setup for directional solidification with pulsed electric discharge Results and discussion Figure 2 (a) and (b) shows the longitudinal and transverse directionally solidified structure of specimen 1# without PED treatment.
Fig.2: Microstructure of directionally solidified Al under different peak intensity of pulsed electric discharge In Figure 2 (a) and (b), the directional solidification structure of pure aluminum in specimen 1# is columnar grains without PED treatment.
When the peak current density is further increased to 135.128KA/cm2, the directional solidification structure in specimen 4# is converted into columnar grains again, compared with specimen 1# without PED, the grain morphology in specimen 4# is more inhomogeneous and irregular, see Figure 2 (g) and (h).

At the lower substrate temperatures, deposited films will have smaller grain sizes with larger grain boundaries which are highly distorted and thus they have large number of defect states.
Therefore the films deposited at higher substrate temperatures will have comparatively larger grain sizes which can cause decrease in the defect states and thereby leads to increase the conductivity of the films [20-22].

From industrial point of view the major obstacle in its use is its low formability capabilities and lower ductility level at room temperature, which are due to hexagonal close packed (hcp) crystal system with a limited number of operative slip systems and thus cold-forming of magnesium alloys is restricted to small deformations with a generous bend radius [4].
Many authors have confirmed that major factors that are affecting SPF are higher temperatures (< 0.5Tm, where Tm is melting temperatures) and fine grain sizes (where grain size is less than 10µm).
Neitzert, Effects of Temperature, Strain Rate and Grain Size on Superplastic Behavior of Magnesium, Ad.

In contrast, there is quite a number of industrial plants in Japan, which, for instance, melt sewage sludge in order to produce vitreous slags as construction material or to turn directly ashes into ceramic products[3].
The grain size variation observed in Fig.1 and Fig.2 was between 2µm and 90µm.
The bigger small particles groupment in Fig.2 caused the smaller variation of grain size.
In SEM results was observed a variation in grain size between 2µm and 90µm. apparently, in sample fired at 1050°C for 3h porosity decreases due to diffusion between particles.

Evaluation Itemn-dressing. number of times, Wsd-the dressed quantity of grinding wheel, Ft-component of dressing force in tangent direction (N), W-Dressing efficiency Results and Analysis Dressing Force and Dresser Wear.
When dressing by rotary diamond dresser, dressing task is well divided to every diamond grain on circular surface and then dresser wear of rotary diamond dresser almost don't happen in limit dressing time.
Optimal value is in 0.25-0.5. 0 10 20 30 40 50 60 70 80 90 0.25 0.5 0.75 1 1.25 dressing ration q dressing efficiency W （um/x50times） dresser diamond grain size 20/25 dresser diamond grain size 30/35 Fig.6 Influence of ration (q) on dressing efficiency Surface of Dressed Wheel.

Introduction Fluidized fly ashes (class C fly ashes) are generated during burning a fine grain mixture of coal powder, fly ash and limestone or dolomite in fluidized-bed boilers, which are burning the air-borne coal dust at lower temperatures (usually up to 900°C) in comparison with the classic burning on fire grates where the burning temperature is up to 1450°C.
Table 1: Residue on a screen with size of 0,063 mm Residue [% mass] Hodonin unmilled Hodonin milled Ledvice 32.2 5.23 54.19 Kaolinic clay B1 was applied as the plastic component in the raw material mixture, as it belongs in the group of refractory clays with a good binding power and sinterability (sintering temperature max. 1250°C) It contains 85 % of grain below 2μm (sedimentation analysis).
The lower percentage of grains under 0.063 mm, the lower is temperature of leakage of SO2.
Acknowledgements This work was financially supported by project “SUPMAT – Promotion of further education of research worker from advanced building material centre” Registration number CZ.1.07/2.3.00/20.0111 References [1] M.