Investigation of Steel Cleanliness on Ti-Stabilized Al-Killed Ultralow-Carbon Steel Grades
(Room 205A)
10 May 17
9:30 AM
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10:00 AM
Tracks:
Tundish Optimization
This work focuses on steel cleanliness to determine the cause of a ladle nozzle clogging problem in Ti-stabilized, Al-killed, ultralow-carbon steel grades. Within this scope, characteristics of inclusions in the ladle nozzle deposit and corresponding liquid steel samples from the RH degasser were investigated by scanning electron microscopy/energy-dispersive x-ray spectroscopy, optical microscopy and x-ray diffraction analyses. During laboratory examinations, Al2O3, MgO.Al2O3 and TiOx-Al2O3 type of inclusions have been detected in nozzle deposits. Consequently, the effect of Ti/Al ratio on the nozzle clogging problem was examined and the critical Ti/Al ratio was determined to prevent nozzle clogging. Accordingly, Ti/Al ratio was modified to prevent the formation of TiOx-Al2O3 inclusions and ladle nozzle clogging ratio has been reduced significantly.