V. E. Ovcharenko

A mathematical model of high-temperature synthesis of the intermetallic compound Ni3Al during ignition

The influence of intermetallic-phase nucleation at the nickel-aluminum interface on the ignition temperature and time of a powder mixture was considered in the framework of a mathematical model for the self-propagating high-temperature synthesis of the intermetallic compoundNi3Al in the regime of thermal explosion of a powder mixture of pure elements. The dependence of the formation rate of the intermetallide on the size distribution of the nickel particles and on the power of the external heating source was studied.

Thermokinetic and Thermal-Physics Parameters of High-Temperature Synthesis of Intermetallide Ni3Al by Thermal Shock of a Powder Mixture of Pure Elements

The paper reports a solution of the inverse and direct problems of high-temperature synthesis of intermetallide Ni3Al by thermal shock. The results obtained are necessary for predicting the kinetics of high-temperature synthesis of intermetallide Ni3Al and its melts. Key words: high-temperature synthesis, intermetallide, thermogram, inert filler, thermokinetic and thermal-physics constants.

Effect of an inert filler on the ignition conditions of a powder mixture of nickel and aluminum

The effect of an inert filler on the time-temperature characteristics of ignition of a nickel-aluminum powder mixture including intermetallide nucleation is examined to determine the possibilities of high-temperature synthesis of composites based on nickel aluminide.

Effect of aluminum content on thermograms of synthesis of intermetallide Ni3Al by thermal shock

Thermograms of high-temperature synthesis of nickel aluminide Ni3Al by thermal shock of powder mixtures of pure elements were studied experimentally by varying the proportion of mixture components within the single-phase composition of the intermetallic compound. A qualitative analysis of the main thermokinetic parameters of the thermal shock versus the aluminum content of the starting powder mixture was made.

Self-Propagating High-Temperature Synthesis of a Ni3Al Intermetallic Compound under Compression

The influence of compacting of a powder mixture of pure elements 3Ni+Al at the initial stage of formation of a Ni3Al intermetallic compound on interfaces of particles of different kinds under conditions of heating of the mixture by an external source of energy is considered. Key words: compact, compression, porosity, high-temperature synthesis, intermetallic compound.

High-temperature synthesis of intermetallide Ni3Al by thermal shock of a powder mixture of pure elements with inert filler

Results are presented of an experimental study of the effect of a high-melting inert filler on the thermokinetic parameters of high-temperature synthesis of intermetallide Ni3Al by thermal shock of a powder mixture of pure elements.

Effects of Inert Nanoparticles of High-Melting-Point Compositions on Grain Structure and Strength of Ni3Al Intermetallic Compounds

The paper represents experimental findings both in the area of effects of nanoparticles of inert high-melting-point TiN compounds on a Ni3Al intermetallic grain structure creation in the conditions of high temperature synthesis under pressure, and in the area of impact of grain structure modification on intermetallic compounds strength factor temperature dependence. It was demonstrated that appending a stoichiometric composition of nanosized particles of high-melting-point inert chemical compounds (TiN) initiates a manyfold loss of average size of grain of Ni3Al intermetallic compounds, synthesized under pressure, as well as a sufficient intermetallic compounds strength rise within a wide range of temperatures (up to 1 000 degree C). Electron-microscopic evaluations of a synthesized intermetallic structure with TiN nanoparticles, showed that, during the process of intermetallic polycrystalline structure creation from high temperature synthesis products melts, TiN nanoparticles are mainly spread throughout the boundaries and joints of grain structure, acting as stoppers of grain boundaries migration.

High-temperature synthesis of the Ni3Al intermetallic compound under pressure

We investigate by experimental and numerical methods the high-temperature synthesis of the Ni3Al intermetallic compound in the thermal explosion mode under the pressure of a powder mixture of nickel and aluminum of a stoichiometric composition. The calculated and experimental thermograms of self-propagating high-temperature synthesis are analyzed depending on the temperature of preliminary heating of the powder mixture and the magnitude of external pressure.

Effect of the heating stage on ignition conditions of a nickel-aluminum powder mixture

In the mathematical model of high-temperature synthesis of an intermetallide compound with the nucleation process at the interface of different components taken into account, the ignition conditions of the initial powder mixture of pure elements by Semenov’s mechanism may be violated.

High-temperature synthesis of a tungsten-free cermet

This paper presents the results of numerical modeling of high-temperature synthesis of cermets on the basis of titanium carbide with a metal binder in the regime of thermal explosion of a powder mixture of pure elements with a metal filler.