Abstract:
The inclusions level present in molten steel interferes directly in the slabs produced by continuous casting and are determinant in surface defects formation in cold rolled products. The steel reoxidation, as well as the slag carried from the tundish to the mold, the interaction of the steel with tundish covering powder and mold flux powder, have a strong influence on the slabs cleanliness originated in solidification process in the mold. In the present work, the inclusions formed during the beginning of the continuous casting process for ultra low carbon steels were evaluated, under three different conditions of addition from tundish powder covering, besides the standard condition itself. The study’s objective is to reduce the inclusions, and consequently, superficial defect in initial slabs and, it will be possible to identify them by means of the relation of the oxygen content in the continuous casting machine strand. Such research was intended to provide information for changes in the process conditions to improve the quality of the final product.