Microstructure and rheological properties of titanium carbide-coated carbon black particles synthesised from molten salt

Abstract

Homogeneous titanium carbide (TiC) coatings were prepared on carbon black (CB) particles by firing them with metallic titanium (Ti) powder in KCl or KCl–LiCl for 4 h at 750–850 °C. As-prepared TiC-coated CB retained the spherical shape of as-received CB, indicating that the ‘template-growth’ mechanism had dominated the reaction process. TiC coating thickness could be readily tailored by simply adjusting the Ti to CB ratio (Ti/C) of the initial starting mixture. The true density of TiC-coated CB particles increased with Ti/C, reducing the density difference between them and other aggregates used in castable systems and potentially improving the castables consistency. Zeta potential measurement, sedimentation comparison and rheology testing revealed that water-wettability and dispersivity of CB were improved significantly after TiC coating.