Modification by Silicon Nitride Nanosized Particles of Materials Based on the Ti–B–Fe System Produced by SHS Extrusion

Compact ceramic SHS electrode materials based on titanium diboride modified with silicon nitride nanoparticles have been obtained by SHS extrusion. The phase composition, structure, and physicomechanical properties of the obtained materials have been studied. The results of scanning electron microscopy showed that, in the modified samples, grain refinement of the main phase of titanium diboride is observed, as well as a change in the phase composition of the material. With the introduction of 5 wt % nanosized particles of silicon nitride, in addition to the main wear-resistant phase TiB 2 , the formation of the following phases is observed: TiN, Fe 2 B, and TiSi 2 located in the FeTi intermetallic matrix. The average grain sizes of TiB 2 and TiN are 0.5–2 and 2 μm, respectively. With the addition of 10 wt % Si 3 N 4 , the structure of the material consists of TiB 2 and TiN phases uniformly distributed in the FeTi intermetallic matrix and a small amount of Si and B solid solutions. The TiB 2 grain size does not exceed 0.5–1 μm, and the TiN phase has an average grain size of about 0.5–1.5 μm. It is shown that the obtained modified ceramic SHS electrode materials have higher microhardness and hardness compared to the material without Si 3 N 4 additives.