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However, the number of commercially available Mg alloys is still limited especially for application at elevated temperature [3].
It is very interesting to note that grain growth was observed at 400oC just after 40 min.
Meanwhile, at 400oC, the recrystallization of Mg-3Al appeared to finish immediately and very coarse grains were observed even after 5 min.
As seen in Fig. 5(a) through (c), even after a long annealing treatment at 200oC from 5 min to 24 hrs, a large number of shear bands are still present in Mg-6Al alloy.
With annealing temperature increased up to 400oC, recrystallization finished just after 5 min and grain growth occurred.

The technological complex of metal items production can be represented as a number of interacting technological processes of downstream product manufacturing of ferrous industry.
The scheme of handling products quality indices in hardware industry technologies: kij, ki(j-1) - meaning of product quality index after j - and (j-1) - technological operation (j = 1….m, m - a total number of technological operations) Measurements and results This theory can be used to forecast the necessary level of mechanical properties of metals and alloys with ultra-fine grain structure for certain operating conditions.
It is a well known fact that ultra fine grain structured carbon steel have specific combination of strength and plastic properties.
So it is very important to forecast mechanical properties of ultra fine grain structured carbon steel for better application.
Conclusions and perspectives The authors carried out a thorough analysis of the technological inheritance issue in the field of metalware production, which made it possible to work out a number of technical and technological measures aimed at suppression or elimination of adverse inheritance links, which might cause a quality gap in the finished product.

Hard materials based on Alumina (AN), Silicon Carbide (SC), Boron Carbide/Nitride (BC/N), Zirconia (ZN), and alike are often used to produce abrasive grains and coat cutting tools.
The variants of AN, SC, BN, BC, and ZN not used for producing abrasive grains and coatings are excluded from the search.
Range compliance provides the compliance in the interval 0,1 of a given range with respect to a given fuzzy number.
Table 1 lists the fuzzy numbers used in this study to define VL, L, M, H, and VL.
Fuzzy numbers used in this study.

Composite of two phases with crystal grains of titanium nitride (TiN) and amorphous of silicon nitride (Si3N4) had shown an improvement of mechanical properties as shown by composite layer of nickel (Ni) and TiN.
The change diffraction peak of Ni crystals is due to the decrease of nuclei number [8].
It was observed that at low current density (2 mA/cm2), the morphology is not compact with large separation between grains and it became more compact when the current was increased.
At current density of 2.5 mA/cm2, the large in sizes and number of agglomerations were appeared on the surface and were reduced for further increased current density up to 3 mA/cm2.
However, in a composite system, the high hardness was achieved by not only crystallite size or grain refinement but also particles dispersion strengthening within the metal matrix [15].

The NdFeB magnets with high density are produced by using fine alloy Nd-Fe-B materials with a grain size of about 1-5 µm [6].
Foto SEM of Nd-Fe-B powder after milling 48 hours Based on observations by SEM, it is seen a relatively homogeneous form of grain with a grain size range of approximately 1-5 µm.
The shape of each grain looks like a plate tetragonal form, where the crystalline form of Nd2Fe14B is shaped tetragonal phase.
Gusak, Grain boundary phenomena in ndfeb-based hard magnetic alloys, Rev.
Science, Vol.28, Number.2, p.185-189(2011).

The hot rolled sheet was constituted by small dynamic recrystallized grains near the surface and elongated grains along the rolling direction in the center.
The traditional heat treatment provided a heterogeneous microstructure with small grains near the surface and large grains in the center.
The average grain sizes are 90 and 144 μm, respectively.
The ductility of the sample (f) decreases because of the relative large grain size.
After the traditional heat treatment, a large number of dimples can be observed on the fracture, indicating certain ductility.

MECHANICAL VARIABLES BLADE as number and position, angle and pressure, sharpness of edges ROLLER as geometry, quality of incision , pressure on tile ROLLER SPEED, that if low, permits a better definition of design, if high, permits a better separation between tiles and a better filling of cavities (to avoid the problem of stripes along the moving direction).
The usual application scheme is : 1) silk screening application of binder only 2) application of dry grains or dry glaze 3) blowing with air The resulting decoration is, than, protected by the application of a fixing agent.
NOT TRADITIONAL DRY DECORATION This means all those techniques that apply solid products, at low grain size, or during pressing phase ( multiple loads ), or just after a first pressing of the tile, by real decoration machinery.
Binders and plasticizers act to form grains, starting from the powders, or to let a pigment adhere on the grain surface, or to obtain a powder right for dry pressing starting from not plastic components, like frits.
Fluidificants for powders are useful to increase the flowing of powders, when dry applied: the most effective of these are based on silica ( ppt or pyrogenic ), having very low grain sizes and acting also as moisture absorbers.

Fine (1-10mm) Mg2Si inclusions were also occasionally found inside magnesium grains.
It comprised a multiphase mixture of Mg- Mg2Si/MgO dispersoids having two sizes of Mg2Si grains one 10-50mm (regular) and one 1-3mm (irregular).
For the 2%MgSiO2 compact, globular Mg grains were surrounded by a thin, multiphase network containing very fine irregular grains of Mg2Si.
The 6%MgSiO2 material was a relatively homogenous mixture of phases containing micro-sized Mg2Si grains.
For both samples some areas showed the presence of Mg2Si nanosized grains mixed with MgO.

Microstructure observation and measurement of linear intercept grain sizes were carried out on an optical microscope.
Fig.1 shows the original microstructure of hot rolled AZ31B magnesium alloy sheet, whose average grain size is about 17.5µm.
Fig.2 also presents that cavities nucleate on the grain boundary, particularly at triangle boundary. this is because of grain boundary sliding which is the dominant mechanism in superplastic deformation.
Although the stress concentration can be released by adjustment of diffusion and dislocation, cavities are likely to nucleate on triangle grain boundary when sliding rate of grain boundary exceeds the limit within which the stress concentration can be accommodated.
(5) Where  0,,n t c c is number density for micro-damage; 0c is nucleation size; c is variation of damage size;  is the shape factor of micro-damage, and for sphere cavities, there is =/6, 3j  ; D is the volume fraction of damage.

Using the high-temperature properties of the plasma arc to strength the metal surface, compared with conventional hardening heat treatment, heating and cooling of the plasma surface hardening process are faster and the crystalline grain is smaller, so it can remain a very high toughness and ductility under the high strength and hardness conditions [4].
In order to reduce the number of trials, we choose the orthogonal test method [5]; according to the sweep length required by the treated workpiece, we choose the nozzle’s diameter at 2.8mm to control the scanning bandwidth; working gas and shielding gas flow were set on 0.025 m3/min.
After being scan by plasma arc beam, the test specimen surface organization changed significantly, the organization grains can be greatly refined.
Using plasma arc beam scan the specimen’s surface, for the energy density of the arc beam is highly concentrated, it allows the temperature of the surface instantly reach the phase transition temperature, nearly melting temperature; due to fast heating, the larger phase transformation driving force, the pearlite is quickly converted into the austenite, while the inner temperature is still at room temperature, after taking away the arc beam, owe to the specimen's own rapid heat transfer, the scan area was cooling rapidly, the cooling rate is far faster than the transformation speed of the martensitic, austenite tiny grain had no chance to grow up, the carbon element in the cooling grain has no chanceto spread out, they achieve self-excitation cold hardening, produce detailed acicular hidden martensite.
Hardened layer have close grains, and arranged in order, its hardness is 1.5 to 2 times of the matrix hardness, about 750 ~ 830HV.