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Cavaliere [4] examined that the microstructure of the materials appears as very fine and equiaxed grains in all the welding conditions.
The fig. 4 (a-f) shows the comparison of TMAZ and HAZ of advancing and retreating side and evidently it shows the variation of grains structures and elongation due to the thermo mechanical action in both of the sides.
Advancing side TMAZ HAZ DRZ Retreating side Fig.3 The graph of Micro hardness at corresponding points in macrostructure. 100µm Fine and elongated grains 100µm Course grains (a).TMAZ Advancing side (b).TMAZ Retreating side 100µm 100µm (c).
HAZ Retreating side Fine and equiaxed grain structure due to the dynamic recrystalization 100µm Grain boundary 100µm (e).
The overall geometry is meshed into small finite number of segments and are connected by means of nodes.

Indeed, the very high volume fraction of dispersoids in these composites leads to an unusually high ratio of interfacial area (between aluminum and spinel) to grain-boundary area (between aluminum grains) as compared with systems like Thoria-dispersed nickel, or oxide dispersion strengthened alloys (ODS) studied to date, because in the latter the dispersoids fraction is very low.
In specimens A the large number of small particles produces a high resistance to the movement of the dislocations [2].
Ideal superplasticity mechanisms predict a strain rate sensitivity equal to one, but a lower value can be explained by a distribution in the grain size such that the large grain regions deform by dislocation creep while the fine grain size regions deform by diffusional creep [6].
Centamore [7] showed that diffusion of both matrix and dispersoid atoms is necessary for the motion of ceramic particles dragged by migrating metallic grain boundary.
Since superplastic flow depends on a very fine grain size, it is likely that the creep resistance of the group A composites can be further enhanced by inducing grain growth at high temperatures.

For the polycrystal model, the material behavior is described using crystal plasticity theory where each integration point in the element is considered to be a single grain of polycrystalline IF steel.
In the crystallographic approach [5-6], the material is assumed to be a polycrystal consisting of many single crystals (grains).
Parallel computing techniques were able to provide a considerable increase in the number of crystals used in the simulations.
The ODF was used to generate a set of 1241 grain orientations for the five ideal texture components.
A neutron diffraction beam was introduced to measure an average texture of an annealed IF steel sheet through thickness direction using the effect of penetration.The ODF was used to generate a set of 1241 grain orientations Crystal Plasticity Finite Element Method The deep drawing process was simulated using the finite element code, ABAQUS [10] with the material model programmed by a continuum crystal plasticity theory.

The initial structure affects the softening processes indirectly, it occurs mainly through the effect of the initial grain size on the recrystallization process.
strain (Tdeformation = 970 oC) strain (Tdeformation = 1050 oC) 1- steel number 8; 2 – steel 9; 3 – steel 10; 4 – steel 14; 5 – steel 11; 6 – steel 15 1- steel number 1; 2 – steel 2; 3 – steel 3; 4 – steel 4; 5 – steel 5; 6 – steel 6 Stress, MPa Stress, MPa a) б) Fig.1.
Table 2 - Parameters of hot compression diagrams (strain rate equal 1 s-1) and grain structure of Cr-Ni austenitic steels.
The high C/N ratio and low grain size (about 5 μm) enhance the increase of resistance to high strains.
According to X-ray diffraction data, this temperature range corresponds to a complete solution of carbides and carbonitrides and provides obtaining of high hardness and preservation of a fine-grained structure [3, 4].

The introduction of boron is contributed by a decrease in the average size of ferritic grains from 8.7 μm (0% B) to 6.2 (0.006% B).
The grain size of ferrite and austenite is determined in accordance with GOST 5639.
Nonmetallic inclusions are represented by a large number of silicate glasses 1–2 μm and rounded oxysulfides based on alumomagnesium spinel in experimental sample with 0,006% B and 0,003% S (Fig. 3a).
The bainitic type structure forms and decreases the size of ferritic grain from 8,7 (0% B) to 6,2 m (0,006% B) with the introduction of boron.
The microalloying of boron steel did not practically affect the size of the austenite grain.

The number of the inclusions in the adding Mg steel decrease more slowly relative to the adding Ca steel with the extension of the steelmaking time.
Using the oxide of high melting-point and high stability to pin the grain boundaries is an effective method to improve the welding performance of the structure steel.
Use the composite microalloy (Nb, V, Ti) to produce grain refinement and precipitation strength [3].
After that, the number of the inclusions in the ca addition sample decreases gradually
The number of the inclusions in the adding Mg steel decrease more slowly relative to the adding Ca steel with the extension of the steelmaking time.

Cycle numbers of 5,500,000 was set as the run-out point, and the deflection of 120% times of the original deflection amplitude was set as the critical maximum value to stop a test.
This might be caused by an experimental error in detecting the smaller pores, because some microstructure features, such as grain boundaries and eutectic phase particles, might also be mistakenly counted as pores by the software Spirit.
As a result, the measured number of pores smaller than 5µm could well be larger than the actual value.
The fatigue test results were shown in Fig.5, where the number of cycles to failure (in logarithmic scale) was plotted versus the alternating stress maximum.
Though has the highest yield strength and the lowest pore density, the A356T6-2 alloy did not show satisfying fatigue properties, which maybe resulted from its higher proportion of large pores and rougher grain size relative to A356T6-1 alloy (Fig.3).

The grain of zirconium electrocorundum in the grinding wheels used in rail grinding trains has specific properties.
It was established [13, 14] that the preparation of the finely dispersed eutectics (fine-grained phase mixtures) is possible at cooling rates ~ 106 °/С and higher.
Fragment of the grain diffractogram with optimal composition.
The particularity of the rail grinding requires combination of the strength characteristics of the abrasive grains with the presence of the micro-shearing effect.
A number of alloying additives with synergistic action in the direction of obtaining of zirconium electrocorundum with specified structural and phase composition was proposed. 4.

In this case, it is possible to detect the dynamics of the process taking into account the time variation in the dielectric and thermal physical parameters of the raw material, calculate the configuration and dimensions of the cavity resonator in accordance with the wavelength and the critical electric field strength, determine the number of sources and their location in the working chamber.
The thawed dough quality assessment Sample number and name Integrated quality indicator Quality 1 sample 11.7 Hardly satisfactory 2 sample 15.6 Good 3 sample 19.5 Excellent Figure 2.
Graphs of organoleptic characteristics of thawed dough Studies were carried out to determine the degree of influence of various ways of defrosting on the structure of starch grains.
A comparative analysis of the obtained microphotographs showed that when using the microwave energy supply during the defrosting stage of the dough the starch grains had a larger shape, which, in our opinion, is explained by the specificity of the action of electromagnetic waves of ultrahigh frequency on the material being processed.
The quality of the product improves by 7 ... 9 points, and the total microbial number in the product is reduced by two orders of magnitude.

After explosion, the surface is at stress state and the metallographic structure still retains the single-phase austenite matrix; and it produces high-density dislocation, stacking fault, cross-slip, lattice torsion, twin-crystal and refinement of austenite crystal grains.
We conducted the abrasive resistance test on the exploded surface for 2min with abrasive grains, a load of 0.5Kg and rotation speed of 60rev.
The results of abrasive resistance test with abrasive grains on specimens before the explosion and after one explosion are given in Table 5.
The reason is that although the metallographic structure undergoes great changes and the hardness and strength improve greatly after the explosive working, the matrix is still austenite (Fig.7) and the surface grain size number is increased by one to two levels, hence, still quite ductile.
The mechanical behavior demonstrated by high-manganese steel after explosive working is attributed to high-intensity of dislocation, cross-slip, twin crystal and kinking of crystal grains inside the metal as well as the fact that the matrix is still austenite (martensite and ε phase change are not found), grain refinement and existence of residual stress in the surface.