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Steel Тtest, [°С] Tensile test Tests for impact strength ElU* [%] magnetization in the field of uniform deformation Magnetiza-tion in the neck magnetization away from the area of destruction magnetization in the field of fracture number of austenite**, [%] 5 Cr18Ni10N (impurity free, N=0,220 %) +20 44 weakly magnetic weakly magnetic non-magnetic non-magnetic 100 -163 31 strongly magnetic strongly magnetic weakly magnetic medium magnetic 96 6 Cr18Ni5Mn9Мo2N +20 40 non-magnetic non-magnetic non-magnetic non-magnetic 100 -163 17 non-magnetic weakly magnetic non-magnetic weakly magnetic 100 * – designation corresponds to table 3; ** – number of austenite in the undeformed samples was determined by x-ray analysis Upon tension at room temperature all steels show high ductility values (Table 3).
High strength, ductility and toughness of such steels can be reached only due to trip-effect or fine grain. 2.
Cr-Ni-Mn steel Cr18Ni5Mn9Мo2N can be used up to -170 °C in wide range of grain size (up to tens of microns), as their temperature of martensite transformation initiation is lower, and such steels allow for elongation up to 20 % at temperatures up to -170 °C.
Tsuchiyama, Effect of grain refinement on thermal stability of metastable austenitic steel, J.

As the thickness of the series of films it influences directly in the electrical measurements, it was necessary to compare the thickness of the series of ZnO:F films with those of ZnO:Al films, increasing the number of layers for the films doped with fluorine.
This widening-effect has been widely interpreted in the reference literature as a product of the losses of orderly in the material or as evident phase changes [12-15]; however, the detailed analysis of the morphological and structural properties as a function of the doped level, indicate that the widening of the diffraction peaks is more related with a dispersion of the sheaf of radiation taken place by the mixture of grains of diverse sizes, as consequence of the formation of small crystals of other compounds in the grain boundaries of the ZnO matrix [11, 16].
Starting from this and making use of the equation derived by Bube for the calculation of the escape time of a hole from a trap [17]       − = kT EEt υ ν τ exp 1 Eq. (1) the number and position of the traps has been determined.
The phenomenon of disabled traps is effective because the size of grain of compounds in the interface of the ZnO crystallites favours the presence of quantum processes among permitted levels inside the band-gap, characteristic of the amorphous materials that transform a polycrystalline material typically insulating and photo-sensitive, in a conductive material.

In fact, two DR peaks are observed in sub-micron grained La2Mo2O9 samples [5], as shown in Fig. 4, where the lower-temperature component (Pd1 peak) has a comparable height with the higher-temperature component (Pd2 peak).
The difference of presentation of the relaxation peaks between macro and sub-micron grained pure La2Mo2O9 samples may result from the lattice distortion in sub-micron grained La2Mo2O9 samples [5].
The crystal lattice of K and Bi doped La2Mo2O9 will be distorted in the vicinity of K and Bi ions since the ionic radius of K + (0.155 nm when coordination number is 9) is much larger than that of La 3+ (0.122 nm when coordination number is 9) [27] and the Bi 3+ ions have a lone pair of electrons although the ionic radius of Bi 3+ is similar with that of La 3+ .

Row number Material Pin Type Pin Length Lpin (mm) Shoulder Type/Diameter Øshoulder (mm) Rotational speed n(rpm) Processing speed v (mm/min).
Grain refinement, an increase in dislocation density, and potential surface defects are just a few of the microstructural alterations brought on by extreme plastic deformation that can be clearly seen in the detailed images of the processed alloy's topography and morphology that are obtained using SEM on a nanometric scale.
A coarse granular structure with grains ranging in size from a few microns to tens of microns is seen on the base material's fracture surface.
There are gaps and crevices between the grains.[8,9,10] According to the chemical composition study, the SFSP-treated sample's higher C content and lower Al content when compared to the base material have a substantial impact on the mechanical and chemical properties of the processed material.
Ashri - A Detailed Study on Friction Stir Welding and Friction Stir Processing–A Review Paper, International Journal of Industrial Engineering & Technology ISSN 0974-3146 Volume 4 Number 1 (2014) 1-22. http://www.gbspublisher.com

A large number of investigations in this area try to define the optimal condition for obtaining high quality joints.
Scanning electron microscopy of sample 1.2 (fig. 3a and b) reveals the cellular dendritic morphology with elongated grains in the weld bead as well as the austenitic structure with twin grains into the base material.
All the samples are characterised by an austenitic column-dendritic grains structure, oriented to the weld central area, in the zone of maximum impact of the laser beam.
Acknowledgements This paper is supported by the Sectoral Operational Programme Human Resources Development (SOP HRD), financed from the European Social Fund and by the Romanian Government under the project number POSDRU/159/1.5/S/134378.

Effectively, the diffraction data enable one to constrain the plasticity model and reduce the number of solutions.
For the (100) oriented grain families and in the case of coarse g’, the g/g’ misfit strain was +0.00022 for the Alloy 720Li and -0.00052 for the RR1000.
Evolution in internal strains during deformation Having shown that there is a significant difference in the misfits strain of RR1000 and Alloy 720Li when comparing specific precipitation sizes, it is of interest to determine whether this difference affects the deformation of the alloys by looking at how load partitions between the matrix and the particles during plastic deformation and between the different grain families making up the polycrystals.
Whilst there are a number of studies which have shown evidence of (100) slip in single crystal superalloys [20, 21], there is only one paper with evidence of (100) slip in polycrystaline superalloys [22].
It only models how intergranular elastic stresses can be relieved by homogenous shear within each grain.

FSC (Fig. 1) is an exhausted foundry sand, which is so fine-grained that it cannot be used for the production of moulds and therefore must be dust-exhausted.
This fine-grained silica sand without contamination, consists of even 95.5% of SiO2.
A number of methods exist for evaluating the performance of antimicrobial coatings, a simple and common method is the agar diffusion test [7].
The test result is the value of antibacterial activity R, counted as an average of decimal logarithms of bacteria number (CFU) immediately after inoculation (U0), 18-24 hours after inoculation (Ut) and in the case of the antibacterial samples, 18-24 hours after inoculation.
Generally, properties of the newly developed antibacterial coatings, containing 30% and 35% of fine-grained (< 63 μm) secondary raw materials, may be regarded as appropriate for use in the environments considered on the basis of comparison with antibacterial coatings currently in use.

A number of reasons have been offered in the literature [2-7] that identify variations in crack closure as the key, by inducing variations in retardation that limits the applicability of the standard ASTM data to VA small crack growth.
To account for a lack of wake for small cracks Microstructural effects can have a significant effect on physically short crack growth rates as some grains have slip systems more favourably orientated to the loading direction.
Each of the changes in loading produces a changed damage state at the crack tip that allows the crack to “choose” a path that on average, across the crack front and in several or many grains through which the crack is traveling, is easier for growth.
This will not necessarily be the easiest path through a particular grain but the easiest path through the material as a whole given the crack’s path to either side of any particular point along the crack tip.
The width of each test band (blocks of CA loads with diminishing mean stress, shown in blue in Fig. 3) was measured and converted to a da/dN value by dividing the band width by the number of cycles (1,000).

Indeed, high energy ball milling (HEBM) has successfully been applied to produce nanocrystalline Mg powders and Mg-based composites [3-6] with significant dehydrogenation-hydrogenation kinetics due to the robust increase of grain boundaries and lattice defects [7].
Surprisingly, CR of Mg-based alloys can be processed in air, at least for small number of rolls, while the hydrogen capacity loss is minimal [12].
XRD patterns of the Mg2Ni powders processed by HEBM and subsequent (a) CR or (b) ECAP techniques for different number of passes.
During the ECAP deformation, the Bragg peaks of the Mg2Ni undergoes a slight line broadening while their relative intensities remains the same, corresponding to a moderate grain refinement and the lack of texture, respectively.
Langdon, Principles of equal-chanel angular pressing as a processing tool for grain refinement, Prog.

The Cr coating exhibits a nodular structure with compact and uniform growth grains of chromium matrix as shown in Fig. 3 (a).
The Cr-Al2O3 nanocomposite coatings are cracks-free due to the incorporation of alumina with chromium matrix refined the grain structure.
The incorporated particles perturb the chromium matrix growth and induce an increase of the number of nucleation sites resulting in a refined grain structure [8, 11-12].
A number of publications reported that the carbon element co-deposited with chromium matrix to form Cr-C [3-4, 14, 19-20].