Powder characteristics, sinterability, and mechanical properties of TiB2 prepared by three reduction methods

Abstract

AbstractReaction processes, powder characteristics, sinterability, and mechanical properties of TiB2 prepared by borothermal reduction, B4C reduction, and boro/carbothermal reduction were compared. Results showed that TiBO3 and Ti2O3 as the intermediate phases existed in the three reduction processes. The temperature where TiB2 became major phase was lowest during borothermal reduction, resulting in the finest TiB2 particle size, in contrast to the other two methods, especially boro/carbothermal reduction. However, TiB2 powders prepared by B4C reduction and boro/carbothermal reduction after pressureless sintering at 1800°C for 2 hours showed the relatively higher sinterability, due to the lower oxygen content and higher carbon content. Finally, using 5 wt% Ni as sintering additive, hot‐pressed TiB2 ceramics from B4C reduction demonstrated higher densification, more fine‐grained microstructure and higher mechanical properties, due to the better balance of oxygen/carbon content.