Evolution and Deformability of Inclusions in Steel Containing Rare‐Earth Element Under Different Deoxidation Conditions
Yeguang Wang, Chengjun Liu
Abstract
The experiments under different deoxidation conditions are carried out on the basis of thermodynamic calculation in the Ce–Si–Al–O–S system. The control conditions of various inclusions and the evolution of inclusions are investigated. The results show that Al 2 O 3 is modified to CeAlO 3 by adding Ce, which is further transformed to Ce 2 O 2 S with the increase of Ce addition in Al‐killed melts. By adding Ce to the melts with Si and Si/Al deoxidation, SiO 2 and SiO 2 –Al 2 O 3 are gradually replaced by Ce 2 SiO 5 and SiO 2 –Al 2 O 3 –Ce 2 O 3 liquid inclusions, respectively. Subsequently, the change of inclusions deformability at low temperature characterized by Young's modulus is calculated in Ce 2 O 3 –SiO 2 –Al 2 O 3 oxide systems. The decrease of Al 2 O 3 content and the increase of Ce 2 O 3 and SiO 2 contents improved inclusions deformability by reducing their Young's modulus. The inclusions deformability is improved by modifying SiO 2 –Al 2 O 3 to SiO 2 –Al 2 O 3 –Ce 2 O 3 inclusion. The Ce 2 SiO 5 with Young's modulus less than 160 Gpa shows good deformability among the RE‐inclusions in this study.