End product rejection rate and its correlation with melt treatment in direct-chill casted hot rolling slabs

Abstract

In this study, different melt treatment operations were evaluated and compared to end product’s scrap rate using bifilm index (BI) method. Results clearly show that degassing with finer gas bubbles increases cleaning performance for the removal of any type of bifilms in the melt. BI method is a reliable and quick way to determine melt quality at any given time during casting process which is found to have a direct correlation with rejection rate.