Modification of Sulfides in a High Sulfur Steel by Cerium Addition

• Published in: Metallurgical and materials transactions. B, Process metallurgy and materials processing science Vol. 53; no. 6; pp. 3992 - 4005
• Main Authors: Yang, Haixin, Ren, Ying, Ji, Sha, Zhang, Lifeng
• Format: Journal Article
• Language: English
• Published: New York Springer US 01.12.2022; Springer Nature B.V
• Subjects: Aluminum oxide; Aspect ratio; Cerium; Characterization and Evaluation of Materials; Chemical precipitation; Chemistry and Materials Science; Eutectic reactions; Inclusions; Materials Science; Metallic Materials; Nanotechnology; Original Research Article; Steel; Structural Materials; Sulfides; Sulfur; Surfaces and Interfaces; Thin Films
• ISSN: 1073-5615; 1543-1916
• DOI: 10.1007/s11663-022-02660-w

The modification mechanism of MnS by the cerium addition in the high sulfur steel was studied through laboratory experiments. The variation route of inclusions was Al 2 O 3 –MnS + MnS → CeAlO 3 –MnS + Ce 2 O 2 S–MnS + MnS with the increase of cerium content in the steel from 0 to 31 ppm. After cerium addition in the steel, rod-like and chain-like MnS inclusions precipitated in the steel were significantly modified into small and spherical ones. The addition of 25–31 ppm cerium can effectively retard the formation of pure MnS inclusions and lower the average diameter, number density and aspect ratio of inclusions. The thermodynamic calculation showed that the addition of cerium decreased the precipitation temperature of MnS and the amount of the precipitated MnS. Meanwhile, the formation of Ce-containing sulfides suppressed the MnS precipitation by the eutectic reaction, resulting in the generation of spherical MnS inclusions by the monotectic reaction.