Affiliation:
1. State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and Technology Wuhan 430081 China
2. Key Laboratory for Ferrous Metallurgy and Resources Utilization of Ministry of Education Wuhan University of Science and Technology Wuhan 430081 China
Abstract
To investigate the formation and evolution mechanism of inclusions in high‐Al steel, four lab‐scaled experiments are carried out with different calcium (Ca) contents. The Al2O3 inclusions are modified to (CaO–Al2O3)–CaS after Ca addition. With the Ca content increased, the types of CAx‐CaS inclusions are changed from CaS‐attached inclusions to CAx‐wrapped inclusions. When the total calcium content (T.Ca) reached 29 ppm, the CAx–CaS inclusions are primarily distributed within the 50% liquidus in CaO–Al2O3–CaS ternary diagram. Some Al2O3 inclusions are not completely modified with 7 ppm Ca addition. CaS and CaO–CaS inclusions are observed with a higher Ca addition. The modification of Al2O3 by CaS and [Ca] occurs in CaS‐attached inclusions with a lower Ca addition. To clarify the formation of CaS, a new modification index for high‐Al steel is given based on the T.Ca/T.O index.
Funder
National Natural Science Foundation of China