Thermodynamic calculation and MnS solubility of Mn-Ti oxide formation in Si-Mn-Ti deoxidized steel

  • Xiao-jun ZhuoEmail author
  • Yuan-qi Wang
  • Xin-hua Wang
  • Hae-geon Lee


Mn-Ti oxides in Si-Mn-Ti deoxidized steels after cooling in the furnace were investigated. The composition and morphology of inclusions were analyzed by using FE-SEM with EDS. Mn-Ti oxides were found to be effective sites to induce intragranular ferrite formation. The thermodynamic calculation was employed to interpret the critical condition for Mn-Ti oxide formation. Mn-Ti oxide formation was controlled not only by Mn and Ti content, but also by total oxygen content in steel. When the Mn and Ti contents were around 1.5% and 0.005%–0.01%, respectively, Mn-Ti oxide could form as the total oxygen content was 0.001%–0.002%. The experimental results were in good agreement with thermodynamic calculation results. Also, MnS solubility was examined in Mn-Ti oxide inclusion system. With an increase of MnO content in Mn-Ti oxide. MnS solubility in the oxides increased. MnS precipitation benefited from high MnO content in Mn-Ti oxide.

Key words

Si-Mn-Ti deoxided steel Mn-Ti oxide MnS intragranular ferrite thermodynamic calculation 


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Copyright information

© China Iron and Steel Research Institute Group 2010

Authors and Affiliations

  • Xiao-jun Zhuo
    • 1
    Email author
  • Yuan-qi Wang
    • 2
  • Xin-hua Wang
    • 3
  • Hae-geon Lee
    • 4
  1. 1.Technology Management SectionChina Minmetals CorporationBeijingChina
  2. 2.Department of Science and Technology InformationChina Iron and Steel Research Institute GroupBeijingChina
  3. 3.Metallurgical and Ecological Engineering SchoolUniversity of Science and Technology BeijingBeijingChina
  4. 4.Graduate Institute of Ferrous TechnologyPohang University of Science and TechnologyPohangSouth Korea

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