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The present study aims to investigate the effect of reinforcing TiB2 particles on the properties of in situ synthesized Ti3SiC2. For this purpose, TiB2/Ti3SiC2 composites with 5, 10, and 15 wt%TiB2 addition were synthesized through spark plasma sintering. TiB2/Ti3SiC2 composites were fabricated by this technique for the first time and the effect of TiB2 addition was evaluated comprehensively in terms of sintering behavior and density, phase development, microstructure, mechanical, thermal, and wear properties. Fully densified TiB2/Ti3SiC2 composites without the formation of any impurity phases were obtained at 1300 °C, for 15 min, under a pressure of 50 MPa. The mechanical properties and thermal diffusivity of composites were increased with the increasing TiB2 content. The most significant effect of TiB2 addition was obtained in wear properties compared to Ti3SiC2 matrix.

The present study investigates the efficiency of spark plasma sintering (SPS) technique on the tribological behavior of tungsten carbide composites, and aims to develop the wear resistance of these composites by addition of cubic boron nitride (cBN). Wear tests of spark plasma sintered 6(wt.%)Co/WC, 25(vol%)cBN/6Co/WC and conventionally fabricated 6(wt.%)Co/WC as a reference sample were performed by ball-on-disk contact with dry and rotational sliding at room temperature in order to determine the friction coefficient and wear rate. Wear mechanisms were explained by using SEM observations and the wear rates were computed by a surface profilometer. In all cases, the major wear mechanisms were observed gradually in the form of microcraking, material removal by grain pull out, and generation and spalling of a tribochemical layer. Based on the experimental results, the addition of cBN considerably enhanced the wear resistance of tungsten carbides. In addition, these results revealed that SPS process has outstanding potential for the fabrication of tungsten carbides with high wear properties for tribological applications.