|About this Abstract
||2017 TMS Annual Meeting & Exhibition
||Computational Thermodynamics and Kinetics
||B-15: Formation and Control of CaS Inclusion in Gear Steel 20MnCr5
||Xu Jie, Fu Jianxun, Wu Yanxin, Li Xu
|On-Site Speaker (Planned)
The modification of (CaO)m(Al2O3)n inclusion and the fact of CaS inclusion formation in gear steel 20MnCr5 after calcium treatment have been studied by thermodynamic equilibrium calculation using the Factsage. Based on the thermodynamic equilibrium, when the liquid steel containing 0.035% [Al],the mass fraction of sulfur is lower than 0.0077% and the ratio of w(Ca)/w(Al) is higher than 0.12,the lower melting point 12(CaO)·7(Al2O3) inclusion will form in the molten steel. The stable CaS inclusion can not form itself under the condition of this composition experimental steel. When the temperature of molten steel drop to 1725.5K and the sulfide content reached 0.0159% at the frontier of solidification, The CaS inclusions are precipitated by the reaction of sulfur with CaO of the surface layer of lower melting point 12(CaO)·7(Al2O3).To avoid it precipitate CaS inclusion in solidification processing, the mass fraction of sulfur must be controlled below 0.000522%.
||Planned: Supplemental Proceedings volume