1987 Volume 27 Issue 5 Pages 344-350
Distribution of Ca-oxide, Ca-sulfide and MnS in Ca-added CC slab was investigated by new X-ray microanalyzer (CMA). The good relation between the amount of MnS and ACR, ESSP which were proposed as the parameter indicating the degree of shape control was not found. It was observed that the formation of MnS was suppressed by Ca addition even in the slab whose oxygen content was too high to form CaS.
On the other hand, calcium-aluminate inclusions were able to be divided into the following two types by the chemical composition: 1) Ca+O type; S enriched region thinly covered this type of oxides. 2) Ca+S type; S was enriched in the whole region of this type of oxides.
Compare to the Ca+O type inclusions, Ca+S type inclusions were mainly observed in the segregated area in CC slabs.
By the thermodynamic consideration, it was found that the desulfurization reaction by calcium-aluminate during solidification should be considered to clarify the shape controlling mechanism.
