Abstract
With intent to make clear the effect of sulfur on the solidification of rimming steel, the properties of low sulfur rimming steel ingots were examined and were compared with that of standard rimming steel ingots.The characteristics of low sulfur rimming steel ingots were summarized as follows:
(1) The number of the elongated blowholes diminishs and the thick solid-skins develope, but some skin holes are formed.
(2) Plenty of MnO (FeO) inclusions are precipitated on the inner surface of blowholes.
(3) Carbon contents of ingots are low in comparision with that of liquid steel in ladle.Sulfur contents of ingots are very low as was expected, but the segregation ratios are rather high.
(4) Sulfide inclusions decrease and oxide inclusions slightly increase, while gross inclusions exceedingly decrease.
These characteristics of low sulfur rimming steel ingots are attributed to the C-O reaction, the fluid motion and the surface tention of liquid steel in mold.
