Control of Low Melting Point Mno-Sio2-Al2o3 Inclusions in Low Carbon Thin-Strip Continuous Casting Steel

International Conference on Materials Sciences and Nanomaterials

材料科学;物理学

Chen, Jing^1 ; Zhu, Qing^1 ; Huang, Di^1 ; Zheng, Shaobo^1 ; Zhang, Jieyu^1 ; Li, Huigai^1

State Key Laboratory of Advanced Special Steel, Shanghai Key Laboratory of Advanced Ferrometallurgy, School of Materials Science and Engineering, Shanghai University, Shanghai

200072, China^1

关键词: Concentration model;    Equilibrium conditions;    Free oxygen potentials;    Interaction activities;    Low melting point;    Oxygen potential;    Thermodynamic calculations;    Weight percentages;   

Others  :  https://iopscience.iop.org/article/10.1088/1757-899X/230/1/012030/pdf
DOI  :  10.1088/1757-899X/230/1/012030

学科分类：材料科学（综合）

来源: IOP

【 摘 要 】

There is a significant difference in the demand for molten steel quality between thin-strip continuous casting and traditional continuous casting. In order to make sure the better surface quality of the thin strips, to generate an oxidation film on the surface of cooling roller is required. This will require that the higher oxygen potential in molten steel and inclusions with low melting point. In this article, the possibility of producing low-melting inclusions which is mainly consisted of SiO2and MnO is studied by controlling the initial oxygen potential and addition order of deoxidizing alloys. The interaction activity between each component in the ternary system of Al2O3-SiO2-MnO is obtained by Action Concentration model. The equal [Mn], [Si], [O], [Al] curve under the temperature of 1823K and equilibrium condition in ternary system of Al2O3-SiO2-MnO is obtained by relative thermodynamic calculation as well. The control method for getting the low-melting point inclusion is as below. While the weight percentage of Si is 0.35% and the one of Mn is 0.90%, in order to maintain the melting point of inclusion around 1200°C, the free oxygen potential in melted steel F[O] should be maintained between 0.002% ∼ 0.004%. On the contrary, the requirement for acid dissolved [Al] content in melted steel is as low as 0.0001% ∼ 0.0005%.