On Segregation in a Super Large Rimmed Ingot

Abstract

A study has been made of sulphur segregation in 22t and 33t ingots. The former has 2800mm in height, and the latter has 1030mm in thickness, both of which are almost the limiting sizes for their blooming mill capacity.
The results reported here are summarized as follows:
i) Position of the maximum segregation is raised up towards top side in a longer ingot, and is lowered down in a thicker ingot.
ii) The maximum segregation of sulphur in an ingot may not be increased even in the 33t ingot, but the analysis from center sheets indicates that the 33 t ingot shows higher segregation than ordinary 17t ingot.
iii) The amount of sulphur segregation is, however, determined predominantly by the ladle analysis. The authors also pointed out that the maximum segregation ratio [(max. S-ladle S)×100/ladle S] is increased with increasing the sulfur content in the ladle.
iv) Those results mentioned above are discussed, referring to the experimental data on solidification in the core zone of ingot.