Analysis of the Causes of Inclusion Agglomeration in 20Mn2K Continuous Casting Nozzle

The internal structure of the source, composition, microstructure, and other characteristics of the adhesive on the outer wall of the 20Mn2K submerged nozzle, and the reasons and mechanisms for the formation of the nozzle slag were analyzed. Preventive measures were proposed. SEM scanning and production process analysis were conducted on the adhesive slag on the outer wall of the nozzle. It was found that the main phases of the adhesive material on the outer wall of the nozzle were CaS and Ca-Mg-Al composite inclusions. Through statistical analysis of production process data, it was found that there was a clear corresponding relationship between the 20Mn2K nozzle adhesive slag and calcium treatment when the content of [Alt] and [S] was high.