Precipitation behaviour of Ti enriched phase in Ti bearing slag

In the present paper, a high titanium molten (high Ti) slag was employed as an additive to modify the titanium bearing blast furnace (Ti-BF) slag in order to investigate the influence of the addition of high Ti slag on the crystallisation behaviour of the Ti-BF slag. The variation in the Ti enriched phase and the precipitation behaviour of the Ti enriched phase in the Ti bearing slag were studied in this paper. The Ti bearing slag in this paper was composed of different proportions of high Ti slag and Ti-BF slag. A combination of X-ray powder diffraction, scanning electron microscope equipped with energy dispersive X-ray spectroscope and optical microscopy was applied to determine the crystal structure, clarify the chemical composition and observe the morphology of the Ti enriched phase. It was found that the Ti enriched phase transformed from CaTiO3 to Mg4Al2Ti9O25 with the addition of high Ti slag. When the Ti bearing slag contained 60 wt-% high Ti slags, Mg4Al2Ti9O25 became the only Ti enriched phase, and it could crystallise completely when the slag was held at 1450 degrees C for 25 min. The formation mechanism of Mg4Al2Ti9O25 is also discussed in this paper.