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The most common carbides are TiC and NbC, which strengthen the grain boundaries, but also precipitate inside grains.
After verifying a number of microscopy techniques in the present work FIB-SEM tomography was used for characterization of morphology and metrology of the γ' and γ" precipitates in IN718 superalloy.
The analysis was based on the histogram performed for each binary image and counting the number of white and black pixels.
The relative fraction of the volume of particles was calculated using the formula: where: n - number of pictures, B - number of white pixels in the image "i", C- number of black pixels in the image "i".
Groeber [7], who writes the application of the EBSD detector to three-dimensional visualization of grains orientation and misorientation in polycrystalline nickel superalloys.

(4) where Γ is the Gibbs-Thomson coefficient, R is the dendrite tip radius, Pei is the Peclet number for i, mi is the liquidus slope, C0,i is the initial concentration for i, ki is the partition coefficient for i (i=Cr or Al),ζc (Pei) is a function of the Peclet number, Iv(Pei) is the Ivantsov solution and Ghkl is the average thermal gradient near the tip.
The size of centerline grain boundary formation is diminished to avoid morphology instability.
Optimum low heat input (low laser power and high welding speed) minimizes not only the weld defects of centerline grain boundary formation, asymmetrical solidification cracking and severe stray grain formation, but also the anomalous microstructure development.
Vitek, The effect of welding conditions on stray grain formation in single crystal welds- theoretical analysis, Acta Materialia,53(2005),53-67
David, Stray grain formation in single crystal Ni-based superalloy welds, Journal of Applied Physics, Vol.94(6)(2003),4203-4209

SEM images confirmed that the as-fabricated Ti2AlC and Ti3AlC2 grains are plate-like with nanoscale layered structure and dispersed uniformly.
Up to now, a number of researchers have successfully prepared Ti2AlC and Ti3AlC2 materials by various methods, such as hot isostatic pressing (HIP), self-propagation high-temperature synthesis (SHS), combustion synthesis (CS), hot pressing (HP), and spark plasma sintering (SPS) [2-4].
From the SEM micrographs of high magnification marked “A” and “B” in Fig. 2 (b), it is clearly seen that the agglomerates mainly consist of fine grains.
According to the XRD results (Fig. 1) and the layered structure, it can be easily known that the layered grains are Ti3AlC2.

In addition, to improve the technological properties and obtain higher-quality products, sumping is used - curing for a certain time and under certain conditions in order to destroy the natural structure, which leads to disintegration of the aggregated particles into elementary grains, an increase in the specific surface and a deepening of the swelling processes, an increase in the number of bound water, an increase in the plasticity and coherence of clay, an improvement in the molding and drying properties [1, 2], the leaching of harmful impurities of soluble salts (su chlorites and chlorides) and others.
A number of works are devoted to questions of possible ways of modifying ceramic masses [1, 4, 15-17], including using silicon carbide [5-6].
Table 1 – Molding properties of clay raw materials Plasticity number Group name Career Humidity Fluidity rate, lL, DE Soil classification, GOST 25100-2011 (paragraphs B.2.9, B.2.10, B.2.12) 9.4 Moderately plastic 19.8 0.3 Loam (7˂ lp≤17); light sandy (7˂ lp≤12, sand ≥40); refractory (0,25˂lL ≤ 0.50) Table 2 – The granulometric composition of the clay raw materials Sample number of the studied raw materials The content of fractions, % wt.
Sand particles (1-0.05) mm Dusty particles (0.05-0.005 mm) Clay particles (less than 0.005) mm 1 40.00 49.64 10.36 2 40.10 48.55 11.35 According to the research, the clay raw materials from the Kubekovskoye deposit belong to loams and are suitable for making solid brick, but do not fall within the maximum strength values on the grain size distribution diagram of grains, indicating its low quality and, accordingly, a significant correction of the charge is required.
Figure 2 – Diffractograms of ceramic masses: red - control composition; black - composition after dispersion Figure 3 – Diffractograms of ceramic masses after firing: red - control composition; black - composition after dispersion Also on diffractograms (Fig. 3), an increase in the intensity of diffraction maxima and a slight decrease in their number in burnt activated-mass samples are observed in comparison with the control samples, which obviously indicates a larger number of tumors and, possibly, the formation of the mullite-like phase at lower temperatures.

Fine grains fill the spaces between cement and aggregate, leading to the denser structure.
In order to obtain fine-grained concrete with good durability, only selected additives and certain chemical admixtures were used.
Experimental Study In the study, it was decided to examine the effects of additives on the technical properties of the protective fine-grained concretes.
In order to compare the boundary mean for a significant factor levels, procedure NIRF was applied (Eq. 1): (1) where: tα, γ - a critical value of the Student's t-distribution at the significance level α = 0.05 and γ degrees of freedom, se2 - the mean square deviation for the error, q - number of factors influencing, n - number of repetitions.
With the right additives you can receive a durable fine-grained concrete.

The surface oxide scale consisted of multi-oxides and the grain size of the oxides increased with increasing holding times.
The grain size of the oxide scale increased with increasing holding time such that after 48 h the oxide scale consisted of coarse grains and contained a large number of pores.

Sequences of fatigue-tension tests were performed on copper polycrystal sheet, with 32µm mean grain size.
The copper sheet, 10 mm thick, cold rolled, was annealed in vacuum at 500°C for 1.5 hours to obtain an equiaxed grain structure with 32µm mean grain size.
In fact, for Φ=0° case, because of the same directions between the two sequential loading paths, most of slip systems activated in tension reloading are active in fatigue preloading, a great number of movable dislocations exist in tension reloading process.
For Φ=45° case, because of the large deviation of the two sequential loading directions, most of the newly activated slip systems in tension reloading are inactive in fatigue preloading, this results in a low number of possible active sources during reloading (see Fig.3(c)).

A suitably fine-grained simple cubic lattice is overlaid on the phenomenological problem.
This quantity is the number of jump attempts per particle.
The number of virtual heat particles in the source plane is Nn.
The increased number of unsuccessful jump attempts in phase 1 simulates an accumulation of virtual heat particles in that phase.
Gust, Fundamentals of Grain and Interphase Boundary Diffusion, Wiley, Chichester, 1995

FTIR Spectroscopy: Figure 6 shows the FTIR spectrum (between wave number 800-2000 cm-1) of the developed Pure Yeast (Specimen-I).
FTIR spectrum of laser irradiated ZnO doped yeast and compared with that of ZnO doped yeast and pure yeast In the earlier work by Pradhan and Sarkar [6] it has been found that the estimated average grain size of the ordinary ZnO is 98.39nm whereas ZnO nanocluster has average grain size 20-40nm.
(TiO2 has average grain size of 40-60nm).
The analysis on grain size was carried out on measured XRD pattern by using Scherrer formula [7].
Table I shows that pure yeast exhibits eight absorption peaks between wave number 1652-1618 cm-1 in Amide I range while laser irradiated yeast exhibits seven peaks in the mentioned wave number range.

The 7475 alloy has a fine-grained size, optimum dispersion and the highest fracture toughness among aluminum alloys, with a high level of strength [16].
They are located at the grain boundaries of α(Al) and surround it form a network intermetallic phases (Fig. 2).
It does not contain pores or signs of melting of grain boundaries.
Cao, Effect of minor Cr, Mn, Zr, Ti and B on grain refinement of as-cast Al-Zn-Mg-Cu alloys, Rare Metal Materials and Engineering 39 (2010) 1135-1140
Chuang, Role of grain size on the stress corrosion cracking of 7475 aluminum alloys, Mater.