Abstract: The nozzle clogging of Ti-IF steel were analyzed by SEM, through the study of nozzle clogging is divided into two layers, including near the nozzle refractory material part reaction layer for Ti-Al-O composite inclusion and Al₂O₃ inclusion mixture, near steel accumulation horizon for Al₂O₃ inclusion and cold steel mixture. The inclusions of steel in tundish were analyzed by SEM, through the analysis found that a lot of Ti-Al-O composite inclusion and Al₂O₃ inclusion in the tundish steel. The Ti-Al-O composite inclusion and Al₂O₃ inclusion is the main reason for the nozzle clogging.

Key words: Ti-IF steel, nozzle clogging, Ti-Al-O composite inclusion