Manufacturing of ceramic nanomaterials in Ti–Si–C–N system by sol–gel method

摘要

Problems concerning sol–gel synthesis of ceramic nanomaterials, methods of investigation of these materials and of processes proceeding with their participation have been presented. One-component nc-TiC, nc-TiN and multi-component TiC + SiC + C and Ti(C,N) + Si(C,N) + Si₃N₄, powders have been investigated. The sol–gel synthesis is carried out in two stages: low-temperature, in which the raw nc-TiC_x product is obtained, and high-temperature one. In the high-temperature stage carbonization of carbides and elimination of excessive organic compounds, being the source of carbon in carbonization process, take place. It has been demonstrated that the oxygen, present at trace level in argon, can react with components of the system in certain range of temperature, influencing the quality of obtained product. High-temperature oxidation resistance of investigated materials in dry air was also determined, applying kinetic methods. TG-DSC measurement data were used as the basis of kinetic analysis. The method of investigation has been presented at the example of TiC + SiC + C powder oxidation. Is has been demonstrated, that in case of multi-component materials, components were oxidized in temperature ranges characteristic for pure phases.