1997 Volume 83 Issue 12 Pages 833-837
The behavior of oxide precipitation during rapid solidification of steel was investigated using Ti deoxidized steel. The number, size and composition of oxides in rapidly cooled steel have been observed and theoretically analyzed to compare with those in slowly cooled steel and continuously cast slab. The results obtained are as follows.
In rapidly cooled steel, whose cooling rate is more than ten times as large as continuously cast slab, many fine oxides smaller than 1μm are observed. The composition of the oxides mainly consists of Ti2O3, Al2O3 and MnO. The Ti2O3 content in the oxide smaller than 1μm is relatively high. By comparing the Ti2O3 content in the oxides larger than 1μm between rapidly and slowly cooled steels, it has been found that Ti2O3 content is lower in the rapid cooling than the slow cooling. As a result of the theoretical analysis of the oxide behavior during solidification, it has been found that the many fine oxides smaller than 1μm precipitate and grow during solidification of steel.