Alexander E Sytschev

Merzhanov Institute of Structural Macrokinetics and Materials Science RAS · Materials science laboratory

Thermal evaporation of Mg particles in the plasma is a more probable explanation for the presence of atomically charged Mg in the SHS reactor. The results can be useful in studying the process of production of magnesium oxide nanopowders and creating SHS plasma generators.

Selective laser melting (SLM) was first used to deposit products made of SHS-produced intermetallic alloy Ti20Al3Si9 powder on the Ti substrate. It was shown that formed Ti20Al3Si9 alloy/Ti substrate composites have a strong bond. The influence of SLM parameters for processing SHS-produced powder on microstructure and phase composition of clad samp...

An metal–intermetallic material based on the combustion products of the layered system (Ti–Al–Mg)/Ti was first obtained using the self-propagating high-temperature synthesis (SHS) combined with pressing. Exothermic synthesis from elemental powders was carried out at a pressure of 10 MPa, and the hot product of synthesis was pressed at a pressure of...

The fabrication of ternary Cu–Mn–Al alloys through self-propagating high-temperature synthesis and their thermoelectric properties, such as electrical resistivity and the Seebeck coefficient in a wide range of temperatures, were studied. XRD analysis identified the Heusler compound Cu2MnAl in the synthesized compositions as a main precipitated phas...

Combustion in the 2Co–Ti–Al system is observed by high-speed video recording. It is established that combustion occurs in the frontal mode, and the process parameters are determined. The maximum rate of the increase in the combustion temperature from the moment of initiation to the maximum value reached is 2.7 × 104 K/s. The front propagation veloc...

—The effect of the angle of inclination of a cylindrical reaction volume relative to the horizontal position on the combustion characteristics of a multicomponent thermite-type mixture FeO/TiO2/B2O3/Cr2O3/CaCrO4/Al/C was experimentally studied. It was shown that the combustion parameters, the burning velocity, material loss caused by sputtering, an...

Data on pore size distribution in solids are obtained by pycnometric density-based methods for measuring the pore structure of materials. The results of measuring open porosity by weighing a dry sample followed by evacuation and saturation with distilled water at atmospheric pressure, impregnation with water under pressure using a hydrostat and mer...

Ni–Al–Co alloy with the composition 45 wt % Ni + 41 wt % Co + 14 wt % Al has been prepared for the first time by aluminothermic reaction. The phase composition of the synthesized alloy comprises a cubic (Ni,Co)3Al solid solution of cobalt in nickel aluminide (γ'-phase) and a tetragonal (Ni,Co)3Al phase. The formation of the tetragonal structure of...

The joining of different intermetallics (e.g. NiAl, TiAl) is important for high-temperature applications. In this study, self-propagating high-temperature synthesis was used for simultaneous joining of (Ni+Al) and (Ti+Al) layered samples of the stoichiometric compositions. The main advantage of such joining by self-propagating high-temperature s...

The determination of the potential characteristics of new thermoelectric materials from the results of measurements of the Seebeck coefficient is described. A device has been developed for measuring the Seebeck coefficient (thermoelectric motive force) of thermoelectric materials in the temperature range 300–800 K in argon, air, or vacuum. The desi...

The method of self-propagating high-temperature synthesis (SHS), combined with pressing, for the first time obtained a metal-intermetallic material based on gorenje products of the layered system (Ti – Al – Mg)/Ti. Exothermic synthesis from elementary powders was carried out at a pressure of 10 MPa, and pressing of the hot synthesis product at a pr...

Впервые комбинированным методом СВС (самораспространяющийся высокотемпературный синтез) и центробежного литья получен интерметаллидный сплав на основе системы 2Ni-Mn-Al. По данным рентгенофазового анализа основная фаза продукта СВС - твердый раствор алюминида никеля (Ni,Mn) 3 Al с частичным замещением никеля марганцем. Исследование микроструктуры п...

This paper reports on structure and phase formation of a Ni–Al–Co based alloy prepared by selfpropagating high-temperature synthesis. The maximum combustion temperature was 1020°C in argon and 913°C in vacuum. The phase composition of the synthesized alloy includes a Ni0.7Co0.3 solid solution with a cubic (Pm m) crystal lattice. Its microstructural...

High density TixZr1-xC (x = 0.15; 0.24; 0.49; 0.88; 0.92) mixed alloys with a submicron structure have been successfully produced by MA-SHS under pressure followed by barothermic treatment (HIP) in a gas-static chamber. The effect of mechanical activation (MA) on the properties of reaction blends containing titanium, zirconium and carbon black powd...

The problem of identifying patterns that are associated with the features of the structure and phase composition of new thermoelectric materials obtained by self-propagating high-temperature synthesis is considered. A measuring device has been developed to determine the Seebeck coefficient (thermoelectric motive force) of thermoelectric materials i...

Decagonal quasicrystals in Al–Co–Ni and Al–Co–Cu systems were first prepared by SHS method. XRD analysis showed that the synthesis of Al–Co–Cu system yields Al70Co15Ni15 quasicrystalline phase; meanwhile, in the Al–Co–Ni system, the synthesized product contains Al70Co15Ni15 quasicrystals as a basis with minor addition of cubic Al58Co76Ni66 phase. B...

The dielectric properties of BN–ZrB2 and BN–ZrO2 based ceramic materials synthesized by self-propagating high-temperature synthesis (SHS) from a powder mixture (boron B, boron nitride BN, and zirconium dioxide ZrO2) in a nitrogen N2 atmosphere were investigated. The experimental results showed that the ceramic synthesized from the initial mixture w...

A few illustrations of material microstructures synthesized by SHS approach https://www.ism.ac.ru/struct/sytschev/res.php

A metal-carbide-intermetallic material based on combustion products of the layer system (Ti-Al-Si)/(Ti-C)/Ti was for the first time obtained with the help of self-propagating high-temperature synthesis (SHS) combined with pressing. Exothermic synthesis from elementary powders was carried out at a pressure of 10 MPa, and pressing of the hot synthesi...

The TixZr1-xC solid solutions were synthesized by electro-thermal explosion under pressure in the (Ti + Zr + C) blends mechanically activated in hexane (MA-ETE). The effect of mechanical activation (MA) duration on reaction blend characteristics, ETE parameters, phase composition, and microstructure formation in solid solutions was investigated....

Processing dispersed fractions of silicon oxides SiOx into polycrystalline silicon in a single argon-hydrogen flow of atmospheric plasma is promising. Some experimental experience has been accumulated on the use of quartz SiO2 for these purposes. Meanwhile, there are almost no data on processing particles of other oxides (e.g., silicon monoxide SiO...

Alloys based on the Ti–Al–Mn ternary system are among the most important in the development of doped titanium alloys for various purposes. In this work, an alloy made of 42.9% of Ti, 24.3% of Al, and 32.8% of Mn (% by weight) is obtained via self-propagating high-temperature synthesis (SHS) during a thermal explosion. X-ray diffraction analysis sho...

The possibility of welding between Ti–Al and Ni–Al layers via self-propagating high-temperature synthesis was demonstrated by using the heat released from the exothermic chemical reaction. The applied pressure and the presence of reactive intermediate layers (Cu, Al) are the most important requirements for strong welding. In the TiAl/NiAl system, t...

The aim of the work is to determine the influence of the hot gas extrusion (HGE) parameters on the phase composition and mechanical properties of composite rods at room temperature consisting of a core with reaction products of a Ni – Al powder mixture and a steel shell. Composite rods were obtained under three different modes of HGE: in the 1st mo...

The possibility of using the method of self-propagating hightemperature synthesis to obtain high-temperature cermet materials and non-removable layer compounds based on (NiAl)/oxide, where the oxides are SiO2, Al2O3 and 3Al2O3·2SiO2, is investigated. The thermodynamic analysis of gorenje reactions was carried out and the properties of the synthesiz...

Dielectric properties of ceramic materials based on BN–ZrB2 and BN–ZrO2 systems synthesized in the mode of self-propagating high-temperature synthesis (SHS) from a mixture of boron B powders, boron nitride BN and zirconium dioxide ZrO2 in an atmosphere of nitrogen N2 have been studied. The experimental results showed that ceramics synthesized from...

High-temperature interaction of 30 wt % Cu–70 wt % Ag eutectic alloy with carbon fibers was studied. It was shown that Cu–Ag drops coated with carbon film are formed on the surface of carbon fibers. Carbon atoms dissolved in the molten Cu–Ag phase precipitated out on the drop surface at a lower temperature, thus resulting in growing few-layer graph...

The influence of Mn addition on combustion synthesis, morphology, phase composition, and magnetic properties of the Ni–Al–Mn alloys was investigated. Ni–Al–xMn alloys with various Mn concentration (x = 0–1.5) were prepared by combined use of mechanical activation and self-propagating high-temperature synthesis (SHS). It was found that the phase com...

Abstract—Ti–24Al–33Mn alloy containing cubic TiMn0.32Al2.68, hexagonal TiMn0.755Al1.246, and Mn3Al2 was prepared by combustion synthesis (SHS method). The synthesized samples were shown to have sufficiently high porosity with individual pore sizes up to 300–400 μm.

Growth of graphene film on the Cu-Ag eutectic alloy surface under conditions of high-temperature interaction with carbon wires.

This paper investigates the features of the high-temperature interaction of carbon fibers with a nickel melt under the action of a short electric pulse and the formation of a multilayer graphite coating on the nickel surface. The saturation of a nickel droplet with carbon is achieved by diffusion on contact with carbon fibers. A multilayer graphite...

The electrical conductivity of powder media depends on the composition, impurities, oxide films, morphology and the nature of the contact surface. We present the results of studying the electrical resistance of powder materials and their compounds under continuous loading by the four-contact method. The electrical resistance is determined using a s...

In this communication, we report on the deposition of copper coatings onto the surface of graphite fibers under the action of pulsed direct current. The EDS analysis of spherivcal Cu particles showed the presence of 80 at % Cu and 20 at % С, which corresponds to interstitial solution Cu(C). The Cu coating was found to consist of either spherical pa...

Self-propagating high-temperature synthesis (SHS) is an attractive technique to synthesize a variety of advanced materials [1]. It is based on the concept that once initiated locally by means of a thermal source of short-term-service, highly exothermic reactions become self-sustaining and yield the final product progressively without requiring addi...

We performed high-temperature treatment of the Ni–C, Al–C, and Ni–Al–C powder mixtures (5 wt % C (soot)) up to the melting point of the respective metals and found that the melt particles coagulate with formation of Ni, Al, and NiAl (intermetallic) spherical particles, respectively. The Ni particles have almost perfect spherical shape and a multila...

Ultra-high-temperature Ta4HfC5 ceramics with a submicron structure has been manufactured from a 4Ta + Hf + 5С powder mixture by electro-thermal explosion under pressure. The effect of the duration of mechanical activation of starting 4Ta + Hf powder mixtures on the structure of the resulting precursor has been studied. It has been demonstrated that...

Lightweight Ti–Al–Si intermetallic alloys with the compositions (wt %) 37Ti–50Al–13Si, 74.1Ti–6.3Al–19.6Si, and 41.53Ti–16.71Al–41.76Si have been prepared for the first time by self-propagating high-temperature synthesis (SHS). Using a 74.1 wt % Ti + 6.3 wt % Al + 19.6 wt % Si mixture, we have obtained a single-phase material with the composition T...

The effect of carbon (3 wt %) on the electrical resistivity of alloys based on aluminum nickelides Ni–Al and Ni–Al–C synthesized by electrothermal explosion in the temperature range of 300–1300 K in a vacuum of 2 × 10–3 Pa has been studied. At an electrothermal explosion in a powder reaction medium, a Ni–Al-based melt is formed in which carbon diss...

We have studied the structuring of combustion products in the Ti–Al system upon interaction with carbon fibers during self-propagating high-temperature synthesis. The combustion products have been characterized by X-ray diffraction and scanning electron microscopy in combination with X-ray microanalysis using an energy dispersive detector. The resu...

The high-temperature treatment of powder mixtures of Ni-C, Al-C and Ni-Al-C (5% wt C (soot)) has been carried out up to the melting temperature of the metals. It was found that melt particles coagulate with the formation of spherical particles of Ni, Al, and the intermetallic compound NiAl, respectively. Ni particles are characterized by the almost...

A composite material based on the Ni–Al–C system is synthesized by the method of an electrothermal explosion at a pressure of 96 MPa. During the electrothermal explosion in a reactive powder medium (Ni + Al + C), a Ni- and Al-based melt is formed, in which carbon dissolves. In the process of crystallization of the final product, carbon, due to its...

In this study we aim at examining the effect of in-situ and ex-situ interfacial ceramic layers at the Al-CNT interface on the thermal expansion coefficient of aluminum matrix composites at different temperatures. For this, two types of bulk composite materials were obtained by a combination of high-energy ball milling and hot pressing methods. Thes...

A lightweight intermetallic alloy containing the ternary phase Al18Ti2Mg3 has been prepared for the first time in the Ti–Al–Mg system by self-propagating high-temperature synthesis. In the binary system Ti–Al, synthesis has been carried out in the thermal explosion regime, whereas in the ternary system Ti–Al–Mg layer-by-layer combustion synthesis h...

Growth of graphene and graphite films on the nickel surface under conditions of high-temperature processing. Examples of deformation and bending of layers under loading.

Combustion of mechanically activated mixtures in 2Co–Ti–Al and Co–2Ti–Al is in�vestigated, and alloys based on them are obtained by self-propagating high-temperature synthesis (SHS). Microstructural, X-ray, and differential-thermal studies are performed. A Heusler phase Co2TiAl-based alloy is obtained for the first time by means of mechanical activ...

A material based on a (VCr)2AlC solid solution has been obtained for the first time by self-propagating high-temperature synthesis from a powder reaction mixture of vanadium(V) and chromium(III) oxides with aluminum and carbon (graphite). The synthesized material has been studied by X-ray diffraction and microstructural analyses. It has been shown...

An intermetallic alloy based on the Heusler phase—Cu2TiAl—has been obtained by self-propagating high-temperature synthesis (SHS) in the Cu–Ti–Al system for the first time. The modes of frontal combustion of the green mixtures and the processes of phase formation during synthesis have been studied. The resulting products have been studied by X-ray a...

In this paper, we studied the effect of carbon (3 wt. %) on the electrical resistivity of materials based on Ni − Al and Ni – Al − C synthesized by the electrothermal explosion in the temperature range 300 – 1300 K in a vacuum of 2·10–3 Pa. During an electrothermal explosion, a Ni – Al-based melt is formed in a powder reactive medium, in which carb...

The catalytic growth of multilayered graphite/graphene on a transition metal substrate (Ni, Co, Cu) and intermetallics (Ni-Al, Fe-Al) is presented. A remarkable example is that (in case of intermetallics) graphene was obtained by self-propagating high-temperature synthesis (SHS).

For the first time, an intermetallic alloy based on the Heusler phase – Cu2TiAl – was obtained by self-propagating high-temperature synthesis (SHS) in the Cu–Ti–Al reaction mixture. The frontal combustion modes of green mixture compositions and phase formation processes during synthesis were studied. The products obtained were studied by X-ray diff...

This study describes the effect of preliminary mechanical activation and SiO2 quartz content on combustion rate, maximum combustion temperature, sample elongation during combustion, compressibility of mixtures, composite particle size, phase composition, and the structural features of combustion products in a Ni–Al–SiO2 system. In Ni–Al–SiO2 initia...

Nowadays the investigation of new lightweight alloys based on titanium aluminides is of great interest. Various low-density dispersion-strengthening additives are used for their synthesis. In this work Ti-Al-Mg lightweight alloy was synthesized using the methods of layer-by-layer combustion and thermal explosion. Relative sample elongation, combust...

The composition and crystal structure of compounds produced by self-propagating high-temperature synthesis (SHS) from the 5Ta-2Ni-3Al (at %) powder mixture followed by vacuum remelting at 3000°C are studied. The SHS product contains the following phases: TaNiAl (Laves τ 1 phase), NiAl, Ni 2 Al 3 , and Ta. Its microstructure includes Ta 85 Ni 7 Al 8...

The TiN/TiAl3/Ti2AlN composite material is fabricated in the filtration combustion mode in nitrogen of porous samples made of the TiAl intermetallic powder consolidated under thermal vacuum treatment. The weight content of each phase, which was 42% TiN, 35% TiAl3, 20% Ti2AlN, and 3% TiAl, is calculated from the X-ray phase analysis data of combusti...

A cermet material based on the system Ni–Al–SiO2 with different SiO2 weight content (0 – 50%) in the mixture was obtained by means of self-propagating high-temperature synthesis (SHS) with preliminary mechanoactivation (MA). It is shown that preliminary mechanoactivation of the powder mixture strongly affects the morphology of the final product. De...

MAX-phase microstructure in the Ti-Zr-Al-C system.

MXene microstructure in the Ti-Si-C system after chemical etching and removal of Si. Self-Propagating High-Temperature Synthesis in the Ti–Si–C System: Features of Product Patterning. S. G. Vadchenko, A. E. Sytschev, D. Yu. Kovalev, A. S. Shchukin, and S. V. Konovalikhin. Nanotechnologies in Russia, 2015, Vol. 10, Nos. 1–2, pp. 67–74.

MAX-phase microstructure in the Ti-Si-C system. Self-Propagating High-Temperature Synthesis in the Ti–Si–C System: Features of Product Patterning. S. G. Vadchenko, A. E. Sytschev, D. Yu. Kovalev, A. S. Shchukin, and S. V. Konovalikhin

The peculiarities of structure and phase formation in the 5 Ta–2 Ni–3 Al intermetallic system are studied in the paper. The TaNiAl, NiAl, Ni2Al3, and Ta phases are found in the alloy produced by self-propagating high-temperature synthesis (SHS). A transition layer with the composition of Ta51Ni20Al29 about 1–2 μm thick is formed on the interface be...

Composite materials based on a 5xxx series aluminum alloy strengthened with 0.1 wt % of multiwalled carbon nanotubes (MWCNTs) or 0.1 wt % WC1 – x/MWCNTs were synthesized by high-energy ball milling and subsequent gas extrusion. The structural phase composition and physicomechanical properties of bulk composites are characterized. A comparison with...

Combustion synthesis experiments in the Ni–Al–C system showed the possibility of obtaining material using carbon components (soot, graphite, carbon nanotubes) in the combustion regime. The carbon predominantly located along the boundaries of intermetallic NiAl grains forms a continuous multilayered film on their surface with a thickness of about 66...

In this communication, we report on the preparation of Ni–Al–C composites by spark plasma sintering (SPS) and their characterization.

Combustion and the formation of structures and phases in a 2Co-Ti-Al system during self-propagating high-temperature synthesis in a thermal explosion are under study. It is determined that a single-phase product (a Co 2 TiAl Geissler compound) can be obtained in this system. Morphology, microstructure, and physical-magnetic properties of combustion...

In this work, the influence of mechanical treatment (mechanical milling) of the TiN titanium nitride powder produced by self-propagating high-temperature synthesis on the magnetic properties of the milled powders is investigated. The effect of d0-magnetization was observed. The TiN powders were characterized by scanning electron microscopy, X-ray d...

Mechanically synthesized hybrid powders of the AMg2/graphite + Al2O3 system and coatings deposited by cold gas dynamic spraying from these powders are studied. The effect of Al2O3 concentration in the powder on surface morphology, structure and microhardness of the coatings formed is determined.

In this paper, we present the results of producing bulk composite materials based on aluminum alloy AlMg2, hardened 0.1-5 wt.% MWCNT and decorated with TiC nanoparticles by powder metallurgy method. Powder and bulk composites were characterized by electron microscopy, X-ray diffraction, kinetic indentation and compression tests. The influence of hy...

Effect of carbon content in a Ni–Al–C system and preliminary mechanical activation on a burning rate, sample elongation, and mixture yield after mechanical activation, as well as on the structural features of combustion products is under study. Combustion in pressed samples from a mechanically preactivated Ni + Al mixture at room temperature could...