Effect of aluminium content on the formation of inclusions in Fe–5Mn–xAl steels

ABSTRACT

The effect of Al content on the characteristics and formation of inclusions in the light-weight Fe–5Mn–xAl steels was investigated in this study. Four synthetic steels with different Al content were produced in the laboratory. The types of observed inclusions were Al₂O_{3 (pure)}, Al₂O₃–MnS, AlN_(pure), AlN–MnS, AlON–MnS, AlON and MnS. Increasing Al content from 0.5% to 6% increased the total amount of inclusions by 2.5 times. As the Al content increased from 0.5% to 3%, the number of AlN–MnS inclusions increased significantly. Moreover, the AlN(pure) inclusions appeared in 6% Al containing steel. Thermodynamic calculations confirmed that AlN inclusions formed during cooling of the steel. It is also observed that AlN can precipitate on Al₂O₃ to form AlN + Al₂O₃ inclusions, classified as multi-phase AlON inclusions in this study. Furthermore, MnS inclusions could co-precipitate with AlN and Al₂O₃ inclusions, but it preferred to co-precipitate with AlN inclusions.

KEYWORDS:

• AlN inclusions
• ASPEX
• inclusion analysis
• light-weight steels
• scanning electron microscope
• Medium manganese steel
• Co-precipitation
• Aluminium

Acknowledgements

The authors would like to express gratitude to the Natural Sciences and Engineering Research Council of Canada (Project No: 20007079) for the financial support for this work. Further, we want to thank Dr. Stanley Sun and Ms. Li Sun at ArcelorMittal Dofasco for their valuable time and fruitful discussions.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Correction Statement

This article has been republished with minor changes. These changes do not impact the academic content of the article.

Additional information

Funding

The authors would like to express gratitude to the Natural Sciences and Engineering Research Council of Canada (Project No: 20007079) for the financial support of this work.