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But, the Fast Fourier Transform-based method has some demerits, such as the lack of a conformal representation of grain boundaries.
The elements of micro-scale and three-dimension have to be used in order to indicate microstructural units, and a large number of elements are necessary.
Although the grain sizes and the grain shapes of the actual materials are non-uniform, in this paper we use a simple virtual material model with particles of uniform size and shape.
Gokhale, Estimation analysis of three-dimensional grain size distribution for microstructural serial sections, Mater.
Rohrer, The distribution and energies of grain boundaries as a function of five degrees of freedom, J.

The SSP setup's blasting intensity was quantified by defining the Almen intensity as 358A, using the number of passes at a speed of 50 mm/s as the time variable.
The material primarily comprises equiaxed grains, exhibiting a range in size with the largest grains approaching 200 µm and the smallest measuring less than 10 µm in width.
These visuals highlight the impact of SSP treatment, resulting in grain refinement at the surface, extending approximately 50 - 100 µm into the material.
This allows for a direct comparison of mechanical characteristics showcasing the influence of refined grain structure and increased hardness of the treated material.
This aligns with the expectation that thinner specimens exhibit a higher proportion of harder and finer grain structure material.

Scanning electron microscopy (SEM), combined with image analysis, was used to determine the grain size and the primary inclusion size of the present material.
The average grain size of GH4169 is about 20µm, but occasionally large grains with sizes of 50µm are also observed.
The microstructure of GH4169 consists of a nickel rich austenite material, strengthened mainly by Ni3Nb type γ'' and partially by Ni3Al type γ' precipitations which are distributed in grains and at grain boundaries.
The number of facets is different in specimens.
For the present specimen, when the crack of the specimens is very short but longer than grain size, the size of plastic zone is also comparatively small, and cleavage fracture emerged.

It can be observed that the number of pores decreased and the grain size increased apparently with increasing sintering temperature.
The surface morphologies of MCT ceramics displayed two different types of grain size: big block-shaped grains and small bar-shaped grains.
The grain sizes varied from 3um to 10um at the temperature of 1300oC for 3h.
It was probable that pores were removed from ceramic as shown in Fig. 3, and abnormal grain growth was emerged when the sintering temperature was higher than 1300oC.

Abstract A comparative study of a Ti-50Al and TiH2-50Al compositions has been carried out to determine the effects of hydride on the structural evolution and powder refinement during mechanical alloying and subsequent grain structure after sintering.
S, Z, M and V are respectively the Rietveld scale factor, the number of formula units per unit cell, the mass of the formula unit (in atomic units) and the unit cell volume (in Å 3).
It is assumed that the grain size reduction effects result in Lorentzian peak broadening, whereas peak broadening due to the microstrain effects is Gaussian, as justified theoretically and experimentally [7, 8].
The presence of a broad diffraction peak at the two-theta angle of 30 degrees for the sample sintered for 2 hours, Fig. 5(a), is most likely to come from the substrate used to fix the pellet. 3.2.2 SEM and EDX analyses SEM images of the sintered samples of both Ti-50Al and TiH2-50Al milled mixtures showed a grey matrix, which is likely to be γ−TiAl and a few bright spots, mainly present at grain boundaries that are likely to be residual Ti (Figs. 6a and 6b).
The sintered TiH2-50Al sample, although with a relatively high number of small porosities, exhibits a relatively small grain size, less than 10 microns (Fig. 6b).

The finely-ground wastes are mostly presented with quartz grains 0.05-0.3 mm in size, magnetite grains 0.3-0.5 mm in size and other ore and gangue minerals.
The strength of concrete depends on a number of factors, and among them on the state of the contact area between the cement stone and the aggregate.
The quartz cleavage face is characterized with the development of a large number of point defects and the elements with uncompensated valences, which are formed at grinding due to the breaking of Si-O bonds in silicon–oxygen tetrahedrons.
A number of research works have been devoted to the issues of strengthening the contact area in concretes.
The role of boundary surface and interfacial phenomena becomes even more significant with the decrease of the composite’s components grain size.

Other properties (average shear modulus, stretch and compression parallel to grain, etc.) can be taken according to the appropriate strength class (Table 1) [16].
Formulas for calculating the mechanical properties of coniferous wood Indicator Formula Note Characteristic value of shear strength (in N/mm2) fm,k – characteristic value of bending strength (in N/mm2) Characteristic value of tensile strength parallel to grain (in N/mm2) ft,0,k = 0.6fm,k Characteristic value of compressive strength parallel to grain (in N/mm2) fc,0,k = 5(fm,k)0.45 Characteristic value of tensile strength perpendicular to grain (in N/mm2) ρk – characteristic value of density (in kg/m3) Characteristic value of compressive strength perpendicular to grain (in N/mm2) fc,90,k = 0.007ρk 5-percentile characteristic value of modulus of elasticity parallel to grain (in N/mm2) E0.05 = 0.67E0,mean E0,mean - mean characteristic value of modulus of elasticity parallel to grain (in N/mm2) Mean characteristic value of modulus of elasticity perpendicular to grain (in N/mm2) E90,mean = E0,mean/30 Mean characteristic value of shear modulus (in N/mm2) Gmean = E0,mean/16 Today, the
largest number of studies of indicators of physical and mechanical properties of domestically produced industrial wood (including pine) has been made according to interstate standards on small "clean" samples, that does not allow to compare existing databases of statistics with class indicators the strengths specified in DSTU EN 338: 2004 [15], due to differences between the schemes and methods of experimental studies.
Differences in methods of investigation of the basic mechanical properties of wood Parameter Standard Sample parameter Load parameter Sample section (h×b), mm The length of the sample (l), mm Speed (v), mm / min; mm / min (t), min Number of load points Distance between centers of support, mm Distance between loading elements, mm Static bending modulus DSTU EN 408 Full size 19h v=0,003h 4 18h 6h GOST 21554.1 21–22h t=2–5 3 9h 4 1/3l GOST 16483.9 20×20 300 v=15±5 4 240 120 Static bending tensile strength GOST 16483.3 t=1,5±0,5 3 GOST 21554.2 Full size 21–22h t=2–5 4 18h 1/3l DSTU EN 408 19h t=5±2 6h Tensile strength for compression parallel to grain DSTU EN 408 6h – – – GOST 21554.4 5h t=2–5 – – – GOST 16483.10 20×20 30 t=1,0±0,5 – – – The fundamental differences in the sample sizes, schemes and loading rates for both small "clean" and for samples (lumber) of wood of full size are revealed.
Characteristic values of strength, stiffness and density of specimens of "clean" pine wood with a section of 20×20 mm Method Data source Indicator Static bending tensile strength (fm,k, MPa ) Static bending modulus (E0,mean, GPa ) Tensile strength for compression parallel to grain (fc,0,k, MPa ) average density1) (ρk, kg/m3) DW2) HW3) DW HW DW HW DW HW GOST DBN V.2.6-161:2010 80 10 44 - According to the research results 67.1±8.7 76±6.2 17.4±2.8 19.3±2.5 42.1±5.8 43.9±5.1 414±33 456±28 DSTU EN DBN V.2.6-161:2017 14–50 7–16 16–29 290–460 According to the research results 50.3±5.3 50.4±5.1 10.2±1.7 10.9±1.4 53.6±5.8 57.8±5.3 475±36 523±30 1) Content of late wood (m, %) – 28.4–53.6 %.

Introduction A number of technologies have been developed over the last three decades, mainly in a laboratory environment, to take advantage of the unique behaviour of semisolid slurries.
It has thus been investigated by a number of workers [1,2,3].
This can be explained by noting that while a lower CS casting temperature yielded a mixture of globular-rosette grains with a fine eutectic, higher CS casting temperature resulted in larger grains surrounded by a coarse eutectic.
Isothermal treatment of CS castings decreased the wear rate due to near-spherical grains and uniformly distributed micro-constituents.
It was seen that, besides grain size and shape, the Si particles have an important role in wear and friction behavior.

We used two different grain sizes of diamond microparticles.
Results and Discussions An important parameter to determine the fidelity of the replicas [16] is the surface roughness ω, defined by Eq. 1 N )ZZ( i 2 avei∑ − =ω , (1) where Zave is the average height and N is the number of points considered in the sample surface (number of pixels).
Comparing the results for samples with "treatment 1 µm" and with "treatment ¼ µm", we see that the reproducibility is better in the second case, where the reduced diamond grain size played an important role in the diamond nucleation, covering better the mold surface.
For the scale between 200 and 400 nm (larger scale) the shift was a factor of 2 smaller that the case of "treatment 1 µm", that is already explained above by the reduced grain size used in "treatment ¼ µm".
The results showed that the reproducibility is better for the sample with "treatment ¼ µm", where the reduced diamond grain size covered more precisely the mold surface, allowing better diamond nucleation.

The growing number of papers [1] reporting on the successful applications of metal oxides in NO2 gas sensing devices show the important role they play in the gas sensor research field.
An alteration in the concentration of the species adsorbed at the surface of the film by the presence of NO2 that either reacts with oxygen adsorbates or directly adsorbs onto the film, leads to a modification in the Schottky-type potential barrier height at the inter-grain boundaries of the film, which results in a change in bulk conductivity.
depletion layers is located at the surface of the grains of the SnO2/WO3 and the second type at the interface between the SnO2/MWCNT and the WO3/MWCNT [10].
Thus, the number of electrons in SnO2/WO3/MWCNT thin film is reduced, and the resistance of the sensor is increased contrarily by adsorbing strongly oxidative NO2.
Like the working principle of an NPN amplifier, MWCNT works as a base, reduce the barrier a little bit and allow a large amount of electrons to pass through grains boundary of SnO2/WO3 (shown as Fig.5).