Affiliation:
1. School of Materials and Metallurgy University of Science and Technology Liaoning Anshan Liaoning 114051 P. R. China
2. Key Laboratory of Metallurgy Engineering Liaoning Province University of Science and Technology Liaoning Anshan Liaoning 114051 P. R. China
3. Technology Center of Baotou Steel Inner Mongolia Baotou Steel Union Corporation Ltd Baotou Nei Mongol 014010 China
Abstract
Seven types of inclusions are observed in the Al‐deoxidized steel followed by Ti‐deoxidized steel, while ten types of inclusions are found in Al–Ti simultaneous deoxidized steel. Three special inclusions are only found in Al‐deoxidized steel followed by Ti‐deoxidized steel as Al2TiO5–TixOy, Al2TiO5–Al2O3–TiS, and Al2TiO5–Al2O3–TixOy–TiS. The precipitation order of inclusions in Al–Ti‐deoxidized steel is very dependent on the value of [%Ti]/[%Al] or [%S]/[%O]. The critical value of [%Ti]/[%Al] for the precipitation of inclusions from large to small is TixOy > Al2TiO5 > Al2O3, and the critical value of [%S]/[%O] for the precipitation of inclusions from large to small is TiS > TixOy. The critical value of [%Ti]/[%Al] for the precipitation of TixOy prior to Al2TiO5, and the precipitation of Al2TiO5 prior to Al2O3 has a close relationship with the content of [%Al]. In addition, the critical value of [%S]/[%O] for the precipitation of TiS prior to TixOy inclusions increases with an increasing content of [%O] and increased with the decreasing of temperature. The precipitation order of inclusions in the two types of steel is Al2TiO5 or Al2O3 → Ti3O5 → TiO2 → Ti2O3 → TiS.
Funder
National Natural Science Foundation of China