Formation and Modification of Al<sub>2</sub>O<sub>3</sub> and MnS Inclusions in Al-Killed Gear Steels via Ca Treatment
A laboratory study was carried out to better understand the factors that contribute to the formation of complex inclusions, as inclusions play an important role during steel production; if not properly managed, inclusions can cause nozzle clogging during continuous casting and also damage the steel’...
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| Format: | Article |
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MDPI AG
2023-06-01
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| Series: | Metals |
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| Online Access: | https://www.mdpi.com/2075-4701/13/7/1153 |
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| author | Haseeb Ahmad Fengqiu Tang Zan Yao Yingtie Xu Zongze Huang Baojun Zhao Xiaodong Ma |
| author_facet | Haseeb Ahmad Fengqiu Tang Zan Yao Yingtie Xu Zongze Huang Baojun Zhao Xiaodong Ma |
| author_sort | Haseeb Ahmad |
| collection | DOAJ |
| description | A laboratory study was carried out to better understand the factors that contribute to the formation of complex inclusions, as inclusions play an important role during steel production; if not properly managed, inclusions can cause nozzle clogging during continuous casting and also damage the steel’s mechanical properties and machineability. To determine the chemical composition of inclusions that are less detrimental to the machineability of Al-deoxidized and Ca-treated gear steels, thermodynamic calculations and automated scanning electron microscopy (SEM) coupled with energy dispersive spectroscopy (EDS), as well as electron probe micro-X-ray analysis (EPMA) with the wavelength dispersive spectroscopy (WDS) technique, were utilized. The findings demonstrated that the morphology of inclusions changed from irregular to a more spherical type and the composition also changed to dual oxy-sulfides from pure oxides and sulfides as the Ca concentration in the steel was increased up to 36 ppm. The amount of Pure MnS sulfides also reduced significantly after Ca treatment. The ternary phase diagram and stability diagram for the inclusions revealed that 15–25 ppm Ca is the optimal range for the modification of both oxides and sulfides into the desired morphology and composition under the stipulation that the concentration of O in the steel is maintained at or below 50 ppm. |
| first_indexed | 2024-03-11T00:50:19Z |
| format | Article |
| id | doaj.art-ef512e1364524099ba02fdf83300b5d3 |
| institution | Directory Open Access Journal |
| issn | 2075-4701 |
| language | English |
| last_indexed | 2024-03-11T00:50:19Z |
| publishDate | 2023-06-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Metals |
| spelling | doaj.art-ef512e1364524099ba02fdf83300b5d32023-11-18T20:28:38ZengMDPI AGMetals2075-47012023-06-01137115310.3390/met13071153Formation and Modification of Al<sub>2</sub>O<sub>3</sub> and MnS Inclusions in Al-Killed Gear Steels via Ca TreatmentHaseeb Ahmad0Fengqiu Tang1Zan Yao2Yingtie Xu3Zongze Huang4Baojun Zhao5Xiaodong Ma6Sustainable Minerals Institute, University of Queensland, Brisbane 4072, AustraliaSustainable Minerals Institute, University of Queensland, Brisbane 4072, AustraliaBaoshan Iron and Steel Co., Ltd., Shanghai 200122, ChinaBaoshan Iron and Steel Co., Ltd., Shanghai 200122, ChinaBaoshan Iron and Steel Co., Ltd., Shanghai 200122, ChinaSustainable Minerals Institute, University of Queensland, Brisbane 4072, AustraliaSustainable Minerals Institute, University of Queensland, Brisbane 4072, AustraliaA laboratory study was carried out to better understand the factors that contribute to the formation of complex inclusions, as inclusions play an important role during steel production; if not properly managed, inclusions can cause nozzle clogging during continuous casting and also damage the steel’s mechanical properties and machineability. To determine the chemical composition of inclusions that are less detrimental to the machineability of Al-deoxidized and Ca-treated gear steels, thermodynamic calculations and automated scanning electron microscopy (SEM) coupled with energy dispersive spectroscopy (EDS), as well as electron probe micro-X-ray analysis (EPMA) with the wavelength dispersive spectroscopy (WDS) technique, were utilized. The findings demonstrated that the morphology of inclusions changed from irregular to a more spherical type and the composition also changed to dual oxy-sulfides from pure oxides and sulfides as the Ca concentration in the steel was increased up to 36 ppm. The amount of Pure MnS sulfides also reduced significantly after Ca treatment. The ternary phase diagram and stability diagram for the inclusions revealed that 15–25 ppm Ca is the optimal range for the modification of both oxides and sulfides into the desired morphology and composition under the stipulation that the concentration of O in the steel is maintained at or below 50 ppm.https://www.mdpi.com/2075-4701/13/7/1153gear steelinclusions characteristicsEPMAsulfide modificationCa treatment |
| spellingShingle | Haseeb Ahmad Fengqiu Tang Zan Yao Yingtie Xu Zongze Huang Baojun Zhao Xiaodong Ma Formation and Modification of Al<sub>2</sub>O<sub>3</sub> and MnS Inclusions in Al-Killed Gear Steels via Ca Treatment Metals gear steel inclusions characteristics EPMA sulfide modification Ca treatment |
| title | Formation and Modification of Al<sub>2</sub>O<sub>3</sub> and MnS Inclusions in Al-Killed Gear Steels via Ca Treatment |
| title_full | Formation and Modification of Al<sub>2</sub>O<sub>3</sub> and MnS Inclusions in Al-Killed Gear Steels via Ca Treatment |
| title_fullStr | Formation and Modification of Al<sub>2</sub>O<sub>3</sub> and MnS Inclusions in Al-Killed Gear Steels via Ca Treatment |
| title_full_unstemmed | Formation and Modification of Al<sub>2</sub>O<sub>3</sub> and MnS Inclusions in Al-Killed Gear Steels via Ca Treatment |
| title_short | Formation and Modification of Al<sub>2</sub>O<sub>3</sub> and MnS Inclusions in Al-Killed Gear Steels via Ca Treatment |
| title_sort | formation and modification of al sub 2 sub o sub 3 sub and mns inclusions in al killed gear steels via ca treatment |
| topic | gear steel inclusions characteristics EPMA sulfide modification Ca treatment |
| url | https://www.mdpi.com/2075-4701/13/7/1153 |
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