CC BY
25iSHS 2019
Moscow, Russia
GRAVITY-ASSISTED METALLOTHERMIC SHS OF COMPOSITES
BASED ON Mo-Ti-Cr-Ni
D. E. Andreev*", K. V. Zakharov", D. M. Ikornikov", V. I. Yukhvid",
and N. Yu. Khomenko"
aMerzhanov Institute of Structural Macrokinetics and Materials Science, Russian Academy of
Sciences, Chernogolovka, Moscow, 142432 Russia
*e-mail: [email protected]
DOI: 10.24411/9999-0014A-2019-10010
Centrifugal overloading is an efficient way to influence thermite mixture combustion with liquid-phase chemical conversion products and combustion regularities: gravity separation of metallic and oxide phases of combustion products, formation of chemical and phase compositions, and structure. Foundations of centrifugal SHS metallurgy of cast ceramics, alloys and composite materials, centrifugal SHS welding on steel substrates, etc. were developed on the base of the basic research results [1-4]. Production technologies for such materials often do not allow achieving the required set of properties and, in addition, are complex multi-step energy-intensive methods. One of the efficient directions in solving the problem of guaranteed increase product quality of these materials while reducing the energy and material manufacture-related costs is the development of a comprehensive technology for the production of Mo-based cast materials.
It is possible to create new functional gradient materials (FGM) and coatings by material-forming combustion processes (self-propagating high-temperature synthesis - SHS). The proposed project is part of the research on the SHS problem of new composite materials. Along with experimental studies, it is planned to simulate the processes of high-temperature synthesis in mixed systems under the action of gravityl forces, taking into account the thermal heterogeneity of the mixture.
The development and modeling of the process of creating new FGM and hard alloys, as well as new methods for applying protective coatings to machine parts and mechanisms, are the most effective directions for creating new machinery, increasing the life of machines and mechanisms operating under conditions of intense wear, temperature. The novelty of the work is the development of scientific foundations of a new technology for the production of composite tubular products by the method of centrifugal surfacing of hard alloys with dispersive hardening of compounds based on MAX phases (Mo2TiAlC2, Mo2Ti2AlC3, Ti2AlC, and Ti3AlC2) generated during the synthesis on steel substrates and mathematical modeling parallel to physical experiments. In the framework of the formation in the synthesis of phase transition in the melt observed in the experiments, it is supposed to take into account the mathematical models of mobility of the liquid phase and to provide the influence of the convective motion of gravity forces on the structure and velocity of the synthesis front.
In the research, experimental equipment and methods for conducting experiments will be developed; regularities and mechanism of gravity-assisted metallothermic SHS of a non-tungsten solid alloy (Mo-Ti-Cr-Ni-Al-C with alloying additives B, O etc.) will be established; the regularities and mechanism of gravity-assisted SHS-surfacing of the free-base solid alloy Mo-Ti-Cr-Ni-Al-C with alloying additives B, O etc. on the inner surface of steel pipes will be established. The expected results will expand the possibilities of managing the material-forming combustion processes and will allow them to be used to produce composite tubes with a gradient structure and will also have the prospect of using them to create new machinery, increase the life of machines and mechanisms operating under conditions of intense wear,
XV International Symposium on Self-Propagating High-Temperature Synthesis
aggressive environments, and high temperatures. In parallel with the formulation and conduct of physical experiments, mathematical models of frontal regimes of exothermic chemical transformation of mixed compounds will be developed. Within the framework of this direction, information will be collected on the features of macrokinetics and on the mathematical modeling of high-temperature synthesis in mixed formulations. From the proposed number of models, the main, as well as effective methods for their numerical solution and corresponding programs for computers will be selected. The results of numerical experiments will be compared with the results of physical experiments.
The research was supported by the Russian Foundation for Basic Research (project no. 19-0300088).
1. V.I. Yukhvid, Modification of SHS-processes, Pure Appl. Chem., 1992, vol. 64, no. 7, pp. 977-988.
2. V.I. Yukhvid, D.E. Andreev, V.N. Sanin, N.V. Sachkova, Energy stimulation of autowave synthesis of hafnium aluminides, Russ. J. Phys. Chem. B, 2017, vol. 11, no. 5, pp. 815-819.
3. D.E. Andreev, D.M. Ikornikov, V.I. Yukhvid, V.N. Sanin, Combustion of a high-calorific thermite mixture on the surface of a titanium substrate, Combust. Explos. Shock Waves, 2017, vol. 53, no. 5, pp. 574-579.
4. V.I. Yukhvid, D.E. Andreev, V.N. Sanin, N.V. Sachkova, Autowave chemical transformations of highly exothermic mixtures based on niobium oxide with aluminum, Combust. Explos. Shock Waves, 2017, vol. 53, no. 5, pp. 580-584.
