I. G. Grigorov

Preparation of MnCo2O4 whiskers and spheroids through thermal decomposition of Mn1/3Co2/3C2O4 · 2H2O

The mixed oxalate Mn1/3Co2/3C2O4 · 2H2O has been prepared in the form of whiskers 2–5 μm in diameter and up to 50 μm in length and spheroidal nanofiber arrays 20 μm in diameter using two different coprecipitation procedures. Thermal decomposition of this oxalate in air has led to the formation of MnCo2O4 particles very similar in morphology to their oxalate precursor. The materials have been characterized by chemical analysis, thermogravimetry, x-ray diffraction. IR spectroscopy, and scanning electron microscopy.

Structural-morphological transformations in titanium nickelide treated in a nitrogen plasma

Powder heterogeneous mixtures produced from a titanium nickelide powder using a plasma technology are studied by electron microscopy, scanning tunneling microscopy, and X-ray diffraction. The quantitative phase composition and morphological features of the powder mixtures trapped by a vortex cyclone and the surface of a fabric filter are determined.

Plasmachemical processing of titanium carbide and nickelide in a low-temperature nitrogen plasma

Nanocrystalline TiCN(TiN)-TiNi(Ni) powders are fabricated by plasma processing of a mechanical mixture of titanium carbide TiC and nickelide TiNi. The morphology, topography, phase composition, and elemental composition of the powder particles are studied by scanning electron microscopy, energy dispersive analysis, X-ray diffraction, and scanning tunnel microscopy.

Peculiarities of Microstructure and Composition of CdSe-PbSe Multilayered Films

The microstructure of end surfaces of CdSe-PbSe films obtained by layered (layer-by-layer) hydrochemical deposition has been studied using X-ray, scanning electron, and scanning probe microscopy. A method aimed at determining the number of layers, their thicknesses, and phase and chemical compositions using a pseudo-three-dimensional image in the ScanMaster package has been proposed.

Phase composition and some properties of titanium carbonitride-titanium nickelide alloys with Al2O3 nanoparticles

The phase formation in and the microstructure of titanium carbonitride-titanium nickelide alloys with aluminum oxide Al2O3 nanopowder additions are studied by X-ray diffraction, electron-microscopic, and electron-probe microanalyses. The phase interaction is characterized by the redistribution of nonmetallic elements and aluminum between refractory and binding phases with the formation of a nonstoichiometric titanium-aluminum (Ti,Al)(C,N) carbonitride and a titanium-aluminum nickelide. The number of forming phases and their compositions are controlled by the kinetic parameters of the process.

Effects of Vanadium and Niobium on the Phase Composition of Titanium-Carbonitride-Base Cermets with Titanium–Nickel Binder

The phase composition of V- or Nb-containing titanium-carbonitride-base cermets with a TiNi binder was investigated, and the content of the alloying metal in the refractory base of the alloys was determined. The alloys were found to consist of three phases: refractory phase, TiNi, and σ-Ni2V3 or NbzNi. The solubility of V in titanium carbonitride is very low, while that of Nb is fairly high and increases with Nb content. The phase composition of the cermets is shown to correlate with the Gibbs energies of formation of the constituent carbides.

Preparation, microstructure, and mechanical properties of TiC0.35N0.35-TiNi cermets

TiC0.35 ±0.04N0.35 ±0.04-TiNi cermets were prepared by liquid-phase sintering of TiG≃0.5N≃0.5 + TiNi + Ti powder mixtures and characterized by electron microscopy, x-ray diffraction, and chemical analysis. The sintering conditions were optimized for different contents of the TiNi binder. The hardness, flexural strength, and average grain size of the cermets were determined.

Effect of alloying on the phase composition of titanium carbonitride–titanium nickelide alloys

X-ray diffraction, electron microprobe analysis, electron microscopy, and chemical analysis are used to study the effect of alloying with zirconium, niobium, vanadium, and molybdenum on the phase composition of titanium carbonitride–titanium nickel cermets. It is shown that two-phase alloys containing alloyed titanium carbonitride and titanium nickelide can only be produced by alloying with zirconium. The addition of niobium, molybdenum, and vanadium leads to the formation of a third phase, namely, NbzNi, Mo(Ti,C), or V4Ni, in the alloy. A correlation between the phase composition of the alloys and the ratio of the energies of formation of titanium carbides and the carbides of alloying elements is found.

Plasma treatment with nickel of vanadium carbide and nitride

X-ray, scanning probe, and high-resolution translucent electron microscopy techniques were used to investigate the structural and morphological features of super- and nanodispersed powders produced by the plasma chemical repeated condensation of mixtures of vanadium carbide or nitride with nickel in low-temperature (4000–6000°C) nitrogen plasma.

Geometry and composition of thin multilayer films based on lead and cadmium selenides

The formation of CdxPb1 − xSe substitutional solid solutions at the interfaces of (CdSe-PbSe)n multilayer films (n = 2–6) is revealed by X-ray diffraction and scanning electron microscopy. The films are fabricated by the hydrochemical layer-by-layer deposition of individual metal selenides. For a six-layer structure (CdSe-PbSe)3, the sequence of layers is determined using gray levels on images by constructing profilograms.