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During welding of a WSTE-51 steel, the V contributes to precipitation hardening by forming carbonitrides at the weld joint as well as a grain refiner [1].
Welding procedures for the WSTE-51 steel plate Electrode Number of passes Voltage (V) Current (A) Pre-heating Welding speed Heat Input Tenacito 60 diameter 4 mm 16 21-25 135-160 175°C 160 mm/min 1.2 kJ/mm After welding, both X-ray and ultrasonic test, applying the usual 70° headset and frequency of 2 MHz, were used for internal inspections.
The presence of V in the WSTE-51 steel promotes fine carbide precipitation in the grain boundaries and favors the nucleation of cracks to accommodate the thermal stresses [2,15].

Large number of bulk properties of kaolinites is determined by the surface properties of the kaolinite.
Presence of deep cracks through the sheets cause a strong decrease in grain size from 45 nm to less than 2 nm as revealed in Fig. 1C.
(C) Profound cracks through the sheets cause a strong decrease in grain size (D) the margins of this small particle fan out and roll up, also leading to a delamination of the particle.

At the same time, because of the rapid solidification high speed steel powder, components uniform, less segregation and grain refinement, the wear resistance of material is improved greatly when compared with traditional fused cast high speed steel [7,8].
As the oxide particles spalled off from the matrix to produce abrasive grains, which resulted in increase of abrasive wear.
As the sliding speed increased to 1.05m/s the oxide film cracked and flaked off, and more white oxide particles scattered on the worn surface, a large number of wear debris re-pressed.

So a number of metal structures are made of this steel, for example, pipelines for transportation of various liquids and gases, various machine parts, steam boilers, oilfield equipment, tanks.
Steel 13Mn6 is compact-grained and contains a small amount of carbon in structure.
Heating under training up to the temperature 950 ºC allows to receive austenite of the increased homogeneity without increase in the size of grain.

Presented research results allow to determine the relationship between the structure, wear resistance, and the specific module responsible for the number, type and position of cathodes used in the constitution of the tested coatings.
The modules that are responsible for the position, number and type of cathodes in the chamber, after the appropriate combination, allow to obtain very good results when it comes to the structure, mechanical and functional properties of the coatings produced.
The areas of coatings dimensioned 5´5 µm were scanned during the measurement, and N=512×512 measurements of specimen height were made, where numbers refer, respectively, to the number of scanned lines and measuring points for each of them.
However, the image of the surface of the breakthroughs of the AlCrSiN 2 coating confirms the existence of a fine-grained nanocrystalline structure and diversified grain size (Fig. 10).
Appropriate selection of the module, position, number and type of cathodes, gives the possibility to obtain very good results about to the structure, mechanical and functional properties of the coatings produced.

The grain size of the copolymer was measured using XRD studies and was found to be 70 nm.
The peak current increased with increase in the number of cycles, which may due to the autocatalytic polymerization, which causes quick poly (OA) film as the electrolysis proceeds [9,10].

The bubbles have tended to distribute along some line in grain body.
In contrast, the specimen implanted deuterium ions formed a large number of defects.
From (a) to (c), the number density after aged gradually increased.
The larger number density, the larger the bubbles growed up whose break need more irradiated dose.

It was found that the introduction of hollow ceramic microspheres into fine-grained sand concrete to a certain extent provides the formation of the concrete structure with a longer "safety zone" (i.e. the stage when the load increase does not lead to a substantial increase in acoustic emission energy and strains).
Results and discussions Earlier [9], the number of ultrasound pulses N and the amplitude A were studied for the analysis of acoustic emission parameters of the samples of high-lightweight concrete during the mechanical testing of compressive strength.
It was determined that the character of the change in the number of AE signals and the total value of the amplitude have similar appearance.
Fig. 2 shows that the application of complex nanomodifier on the surface of ceramic microspheres allows increasing the strength of lightweight concrete in proportion to the number of hollow filler.

Bisantino2,3 found that viscosity and yield stress of different grain size debris flow can be used to evaluate characteristic of debris flow; Yuyi WANG determined viscous debris flow’s stress-strain curve adopted home-made debris flow rheometer and found stress-strain curve have characters such as stress-overwing, shear desaturation and shear expansion; Major considered that fresh debris flow deposit consolidate under gravity, and debris flow of contraction distortion generates with the evanesce of pore-water pressure, while, consolidation speed affect the resistance of debris flow be renewal moving and depositional characters of debris flow.
(4) Unsaturated debris flow deposit is four-phase system, composed by water, air, soil grain and water-air boundary surface (called shrinking film either).Soil grain and shrinking film will keep balance at the action of force, while, air and water will flowing at the action of stress gradient.
Assuming that soil grain is incompressible and the volume of shrinking film is constant, the variance ratio of unsaturated debris flow’s total volume is the sum of liquid phase and gas phase’s volume.
(27) Where, Vs relates to volume of soil phase grain in saturated debris flow plasma, that.
(31) Where, m is positive odd number; Tm(t) is time function need to be solved which can be expressed as follow (32) Where,, .

The biggest natural disaster in Indonesia in term of a number of people killed and other impact on exposure area is caused by earthquake.
One of the result of grain size analyses from ten soil borings is shown in Fig. 4.
This figure shows relation between grain size characteristics of soil layers and liquefaction potential.
Grain size distribution of SB6 S-11 S-36 Fig. 5 a.
The result of grain size analyses show that all sample from almost all soil layers in the study area are vulnerable to liquefaction.