The influence of silicon oxide, aluminum oxide, silicon nitride and titanium on the formation of a solid solution of carbon in silicon carbide

DOI: 10.62564/M4-YT1353

Yaroslav Tymoshenko, Mykola Gadzyra, Nadiya Davydchuk, Mykyta Pinchuk

Frantsevich Institute for Problems of Materials Science National Academy of Science of Ukraine


The formation of a solid solution of carbon in silicon carbide occurs due to the partial replacement of silicon positions by carbon atoms, which leads to a decrease in the β-SiC lattice parameter and an increase in the hardness of polycrystals sintered at high pressure, which is 30% higher than the hardness of a SiC single crystal [1]. The objective is to examine how a solid solution of carbon in silicon carbide synthesizes in the interaction of carbon with silicon in the presence of SiO₂, Al₂O₃, Si₃N₄ and Ti. To obtain a composite powder material, petroleum coke and silicon were used as starting components. 30 wt.% of SiO₂, Al₂O₃, Si₃N₄ and Ti powders were added to the powder mixture С–Si. Synthesis of composite powder material were carried out at a temperature of 1200 °C in air during 1 hour. It was established that the interaction of the components in the С–Si system with the addition of SiO₂, Al₂O₃, Si₃N₄ and Ti occurs with the formation of SiC, SiO₂, Si₃N₄, Si₂N₂O, Al₂O₃, SiAlON and TiCN. It was established that the addition of SiO₂ contributes to the formation of a solid solution of carbon in silicon carbide with the lowest lattice parameter 0.4349 nm. It is shown that the presence of Al₂O₃ in the composition of the charge leads to the formation of a silicon carbide structure with a standard value of the lattice parameter 0.4359 nm. It was investigated that the addition of Si₃N₄ to the composition of the charge leads to the formation of a solid solution of carbon in silicon carbide with lattice parameter 0.4351 nm. It was found that the presence of Ti during the synthesis of silicon carbide does not contribute to the formation of a solid solution of carbon in silicon carbide, since its lattice parameter 0.4357 nm is closers to standard value.

Keywords
a solid solution of carbon in silicon carbide, silicon nitride, aluminum oxide, sialon, titanium carbonitride

Acknowledgments
Not provided

References
[1] Mykhaylyk O., Gadzira M., Arrangement of C atoms in the SiC–C solid solution, Acta crystallographica, 1999. V.55, No. 3. P.297–305.