Changes of Non-Metallic Inclusions for Low-Carbon Aluminium-Killed Steel Sheet at the Start of Continuous Casting

Systematical analysis of changes of non-metallic inclusions at the time of casting start was taken.Samples were continuously taken from the liquid steel of the tundish during the time of casting start of SPHC steel continuous casting.Total oxygen content,nitrogen content and non-metallic inclusions of the samples were analyzed in detail.It is found that,at the time of casting start,the reoxidation of the liquid steel in the tundish is serious.The liquid steel in tundish reaches a more stable state after time of about 21 minutes from the time of casting start.Calcium treatment can modify non-metallic inclusions and reduce the nozzle clogging.