Composites based on boron carbide (B₄C) have attracted considerable attention because of their outstanding physical and chemical properties. As part of this research, by using appropriate reagents, including boron carbide, carbon, and selected intermetallic mixed in appropriate molar proportions, it was possible to obtain a composite that consisted of 99% of the reacted starting materials. Composites were prepared using three different methods: pressureless sintering, hot pressing, and spark plasma sintering (SPS). The use of intermetallics during sintering, depending on the method used, significantly reduces the synthesis temperature, and the control of both the additive used and its amount allows the modification of the obtained compositions of composites after sintering.

Different sintering temperatures were used for each consolidation process. For free sintering, the synthesis was conducted at 1650°C-1750°C, for hot-pressing and SPS it was possible to lower the synthesis temperature to 1500-1550°C and 1400-1450°C, respectively. The mechanism of potential chemical reactions is related to the type of intermetallic phase used; surprisingly, the simple and lower-temperature method according to the invention [1] is possible only because of the use of a phase in the form of intermetallic (TiSi, TiSi₂, Ti₅Si₃) in combination with the appropriate molar proportions of the reactants used. This process eliminated carbon from the final composition of the material. This was an unexpected effect, especially when using a commercial boron carbide B4C substrate, which usually contains carbon in the form of graphite. The obtained high-temperature refractory TiB₂-TiC-SiC composite showed high mechanical strength and fracture toughness [2]. The chemical reaction that occurs during sintering is very effective. Almost 99% of the initial phases decomposed and allowed the formation of new TiB₂ and SiC phases, which were well-densified at relatively low temperatures. The TiC phase was formed only when no boron was present in the system during sintering. Hence, in the case of the addition of Ti₅Si₃, when there was a significant amount of Ti in the system and a lack of boron, a small amount of TiC phase was formed [3].