Improved slag resistance of taphole clay due to in situ formation of TiCN from ferrotitanium slag

Abstract

To improve the slag resistance of taphole clay, we prepared it using ferrotitanium slag as raw material. TiCN was formed in situ in the taphole clay. The formation mechanism of TiCN were studied by using X-ray diffraction (XRD) and field emission scanning electron microscopy (FESEM). Results showed that TiCN can be formed by a series of reactions among CaTiO3 in the ferrotitanium slag, N2 in the atmosphere, C and Si3N4 in the taphole clay. We investigated the slag resistance of the resultant taphole clay by FESEM and compared the results with that of taphole clay prepared using brown fused alumina as a raw material. Improved slag resistance was observed in the taphole clay that used ferrotitanium slag as a raw material due to the behavior of TiCN. When the taphole clay was in contact with the molten slag at 1450 °C, TiCN was continuously distributed over the erosion interface, forming a protective layer and dispersed in the slag near the erosion interface, thus improving the slag resistance of the taphole clay.