Combustion synthesis of TiB₂ ceramics powder from B₂O₃−TiO₂−Mg system in air atmosphere

Abstract

TiB₂ ceramics powder was synthesized from B₂O₃−TiO₂−Mg system. The effects of TiB₂ addition as diluent on the combustion synthesis process were investigated. The results of thermodynamic calculation and experiments show that the increase of TiB₂ content ranging from 0 to 20wt% can reduce the adiabatic temperature T_ad from 3100 K to 2896 K and combustion temperature T_c from 2139 K to 1621 K respectively. The particle size and half width of the particle distribution are also increased with the addition of TiB₂ increasing from 0 to 20wt%. The combustion product is a mixture of TiB₂, MgO, and other intermediate phases. The leached product contains mainly TiB₂, TiO₂ and TiN, and its oxygen content is 7.77wt%.

Keywords

combustion synthesis / B₂O₃−TiO₂−Mg / TiB₂

References

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