Abstract
The influence of various deoxidizers on the rimming action was studied by making 330 kg ingots.
Each deoxidizer was used only during the teeming of an ingot, without the addition of deoxidizers during tapping.
The state of rimming action, the quantity of foam in the soldifying liquid steel, the structure of the ingot, the degree of the negative segregation of carbon in the rim zone, and the characters of deoxidation-products were observed.
It was found that the deoxidizers were classified into the two groups, rimming-promoting deoxidizers and rising-promoting ones, from the different influence on the rimming action.
We presumed that this difference was caused by the different influence of these deoxidation-products on the life of the foam in the liquid steel, which came from the difference of the melting point of each deoxidation-product.
