Sintering mechanism of the in situs park plasma synthesized TiB-TiB₂ ceramic composites

TiB-TiB₂ ceramic composites were synthesized in situ by the spark plasma sintering method at different temperatures. The microstructure, the mechanical properties as well as the sintering mechanism of the TiB-TiB₂ composites were investigated. According to the microstructure evolution of the in situ synthesized TiB-TiB₂ composites, the sintering process can be divided into the following 4 stages: activation and melt of the metal powders, reaction of Ti with TiB₂, coarsening of TiB whiskers, and rapid densification. Only if the four sintering stages mentioned above proceeded in turn and completed fully, the TiB-TiB₂ ceramic composite with dense microstructure and good mechanical properties can be obtained.