Fabrication, microstructure and properties of Fe–TiC ceramic–metal composites

Ceramic–metal composites based on the Fe–TiC system can be synthesised by reduction of the mineral ilmenite (FeTiO3) with carbon in flowing argon or under vacuum in the temperature range 1100–1400 °C. The ratio of Fe:TiC can be controlled through adjustment of the reactant materials, as can the addition of alloying metals such as Co, Cr or Ni. Dense bodies formed by sintering Fe–TiC powders display a microstructure of uniformly dispersed TiC grains in a continuous metal matrix. The grain size of the TiC can be controlled between 1 and 20 μm by varying the heat treatment schedules. Hardness values of 14 GPa can be achieved through pressureless sintering of unalloyed Fe:3TiC bodies. Technologies have been developed for fabricating a range of compositions from 6 wt% to over 80 wt% TiC in iron alloy matrices, leading to broad suite of potential industrial applications as wear parts or cutting tools.