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The cathode material was TC11 alloy with fine -grained equiaxed structure, which includes ~ 88% Ti; 6.5% Al; 3.5% Mo; 1.5% Zr, and 0.3% Si (Wt).
However, on all samples coated with selected electrode materials there is no pronounced heat-affected zone in the substrate, characterized by a decrease in grain size of the matrix material, that usually appear under the surface layers due to exposure to high temperatures during electro-spark treatment [3].
During testing of the samples delamination of heat scale was not revealed, but increased the number and size of microcracks on a surface.

A representative volume is necessary to sample a statistically relevant number of grains contributing to the diffraction peak of the coarse-grained matrix.

The micrograph shows a pattern of constituents: (i) the dendritic structure of the weld metal (top), (ii) the coarse grained ferrite-pearlite structure, (iii) the fine grained ferrite-pearlite structure and (iv) the parent metal of deformed ferrite-pearlite structure (bottom).
In addition, there is an increased number of 180o domain walls in the tensile stress direction [9] which contribute to an enhanced signal.

These shapes of the macroscopic cracks were caused by inclusions (large grains) occurring in the concrete structure placed in the vicinity of the crack paths.
In case of the concretes FA-30 we observed the curving of the crack paths and a large number of branches.
Golewski, Effect of aggregate kind and graining on modeling of plain concrete under compression, Comput.

It produced a large number of asbestos tailings piling up mostly in the mining area, which not only caused great waste, but also bringed the pollution into the mining area of water, air and soil.
The traditional application of serpentine has relatively strict requirements of its grain size and chemical composition, for example the grain size of serpentine used as iron flux is 10-30mm, its MgO>38%; that used as refractory requires its MgO>40% and CaO<0.8%.Therefore,there would be a mass of serpentine tailings produced in the course of serpentine application.

With increasing the milling time, the number of phases was decreased and only Al2Y phase retained in the powder after milled for 100h.
For a phase transformation process related to nucleation and growth of grains, the JMA equation is a helpful tool to describe the corresponding transformation mechanism [13].
By this equation, we have the following equation in the non-isothermal condition, (4) where x(t) is the crystallized volume fraction at time t; is the Avrami exponent related to nucleation and growth of grains and is the reaction rate constant related to absolute temperature and activation energy; is the incubation time.

The formula for the auxiliary constant ψ is: ψ=ApEpAhEht . (4) Modulus of elasticity of rock mass in the time (see Table 2) of pre-tensioning Eht[3] Eht=E1+ϕ , (5) ϕ=δ.t1-α1-α . (6) Table 2 - Rheological constants[3] Rock δ α Claystone 0.0157 0.89338 Siltstone 0.00947 0.87255 Medium-grained sandstone 0.00713 0.63503 Coarse-grained sandstone 0.04017 0.57291 ANCHorage Loss As has already been mentioned above anchorage losses are losses due to wedge draw-in back into the barrel after releasing the pre-tensioning jack.
Table 5 - Results of relaxation losses measurements Test number Type TC F0 ΔFP FP w ξP T100% ΔFT100% ΔFT24h [h] [kN] [kN] [kN] [mm] [%] [h] [kN] [kN] 1 Hand 1006.5 350 218 132 2.16 62.3 48.00 8 7.5 2 Hand 238.0 350 210 140 2.29 60.0 3.81 6 6 3 Hand 214.0 350 195 155 2.54 55.7 1.87 6 6 4 Hand 316.0 350 190 160 2.62 54.3 92.51 6 4 5 Hand 115.0 350 211 139 2.28 60.3 18.50 3.5 3.5 6 Electric 1003.0 350 211 139 2.28 60.3 48.00 8.5 6.5 7 Electric 286.0 350 210 140 2.29 60.0 119.00 6 2.5 8 Electric 146.0 350 180 170 2.79 51.4 71.00 2 2 Average 203.13 146.88 2.41 58.04 Explanations: TC total test time, F0 loading force, ΔFP initial force in cable after deducting anchorage wedge draw-in, FP anchorage wedge draw-in loss, w anchorage wedge draw-in, ξP spring efficiency, T100% time of 100% relaxation loss, ΔFT100% total loss during 100% relaxation, ΔFT24h relaxation loss after 24 hour.

In the initial stage of tension of the sample, the grain slips, forming slip lines with different directions.
With the increase of deformation, the number of slip lines also increases, resulting in the gathering and entanglement of dislocation.
At the internal grain defects areas such as stacking fault and dislocation, the local stress continues to increase due to the functions of dislocation glide and deformation twins trimming.

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.

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].