Abstract
The phenomenon that molten pig iron containing titanium swelled and drooped when heated in levitation melting was observed. To clarify the mechanism of the phenomena, various iron containing carbon, titanium and nitrogen was melted under argon or nitorgen.
Swelling phenomenon is caused by nitrogen gas evolved by decomposition of titanium compound in molten iron. Drooping phenomenon is caused by decrease in surface tension of molten iron by rapid nitrogen absorption. These phenomena were considered to relate with various troubles in blast furnace operation occurred at a heavy charge of titania-contained ore.