Self-propagating high-temperature synthesis, microstructure and mechanical properties of TiC-TiB₂-Cu composites

TiC-TiB₂-Cu composites were produced by self-propagating high-temperature synthesis combined with pseudo hot isostatic pressing using Ti, B₄C and Cu powders. The microstructure and mechanical properties of the composites were investigated. The X-ray diffraction (XRD) and scanning electron microscopy (SEM) results showed that the final products were only TiC, TiB₂ and Cu phases. The clubbed TiB₂ grains and spheroidal or irregular TiC grains were found in the microstructure of synthesized products. The reaction temperature and grain size of TiB₂ and TiC particles decreased with increasing Cu content. The introduction of Cu into the composites resulted in a drastic increase in the relative density and flexual strength, and the maximum values were obtained with the addition of 20 wt pct, while the fracture toughness was the best when Cu content was 40 wt pct.