Fe–Sialon–Ti(C,N) composites from carbothermal reduction–nitridation of low-priced minerals and their application in taphole clay refractories

Fe–Sialon–Ti(C,N) composite materials were first synthesized via carbothermal reduction–nitridation reaction with low-priced mineral materials, such as ilmenite, quartz, aluminum dross and coke powders, as starting materials. Effects of temperatures on the phase compositions and microstructures of products were investigated. The investigation results indicated that the optimal synthesis temperature was 1550 °C. Rise in synthesis temperature was beneficial for the synthesis of Sialon and Ti(C,N). The as-fabricated Fe–Sialon–Ti(C,N) composites were used as additives to produce taphole clay refractories, and the bending strength and erosion resistance against blast furnace slag of taphole clay refractories were studied. Taphole clay refractories with 20 wt% Fe–Sialon–Ti(C,N) composite materials still owned good slag resistance. Bending strength of taphole clay refractories increased with the addition of Fe–Sialon–Ti(C,N) composite materials; when 15 wt% Fe–Sialon–Ti(C,N) composite materials were added, bending strength reached its highest value of 13.36 MPa.