Effect of titanium content on the precipitation behavior of carbon-saturated molten pig iron

Abstract

The use of iron ores bearing titanium as a raw material is an effective measure to prevent hearth erosion and prolong the life of a blast furnace. In this research, the effect of titanium content on the precipitation behaviors of high-melting phases of carbon-saturated molten pig iron were studied by confocal scanning laser microscopy. The results showed that, when the titanium content was less than 0.25wt%, Fe₃C was precipitated as a single phase from the molten carbon-saturated iron. The growth rate of the precipitated Fe₃C crystals was very high, reaching 7387 μm²/s. When the titanium content in the molten pig iron was greater than 0.47wt%, TiC crystals precipitated first. The shape and size of the precipitated TiC crystals did not obviously change. After TiC was precipitated, the fluidity of the molten pig iron worsened. With a decrease in temperature, Fe3C was also precipitated but the growth rate of Fe3C was limited by the presence of the first precipitated TiC phase. The crystal size of the precipitated Fe₃C was much smaller than that of pure Fe₃C.

Keywords

carbon-saturated molten pig iron / precipitation behavior / titanium / titanium carbide / confocal scanning laser microscopy

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