1 College of Materials Science and Engineering, Chongqing Key Laboratory of Vanadium–Titanium Metallurgy and Advanced Materials, Chongqing University, Chongqing 400044, China
Properties and structure of a new non-reactive mold flux for high-Al steel
1 College of Materials Science and Engineering, Chongqing Key Laboratory of Vanadium–Titanium Metallurgy and Advanced Materials, Chongqing University, Chongqing 400044, China
摘要 During the conventional continuous casting process of high-aluminum steels (w([Al])[ 0.5 wt.%), some components of slag, such as SiO2, B2O3, and TiO2, could be reduced by aluminum in molten steel. Therefore, the CaO–BaO–Al2O3– CaF2–Li2O non-reactive mold fluxes were designed using the simplex grid method and molecular dynamics to mitigate the slag–metal interface reaction and stabilize the performance of mold fluxes. The results show that the components of nonreactive quinary system are 20–40 wt.% CaO, 14–34 wt.% BaO, 14–34 wt.% Al2O3, 4–12 wt.% F, and 4–8 wt.% Li2O. Molecular dynamics simulation results show that [AlO4]- tetrahedron acts as network formers and melt network structure is mainly chain and lamellar in the low-viscosity area. The cross sections of w(F) = 8 wt.%, w(Li2O) = 8 wt.% and w(F) = 12 wt.%, w(Li2O) = 8 wt.% are important reference sections for the design of mold flux, with the compositions of 22–40 wt.% CaO, 14–34 wt.% BaO, 20–34 wt.% Al2O3 and 23–40 wt.% CaO, 14–34 wt.% BaO, 20–28 wt.% Al2O3, respectively.
Abstract:During the conventional continuous casting process of high-aluminum steels (w([Al])[ 0.5 wt.%), some components of slag, such as SiO2, B2O3, and TiO2, could be reduced by aluminum in molten steel. Therefore, the CaO–BaO–Al2O3– CaF2–Li2O non-reactive mold fluxes were designed using the simplex grid method and molecular dynamics to mitigate the slag–metal interface reaction and stabilize the performance of mold fluxes. The results show that the components of nonreactive quinary system are 20–40 wt.% CaO, 14–34 wt.% BaO, 14–34 wt.% Al2O3, 4–12 wt.% F, and 4–8 wt.% Li2O. Molecular dynamics simulation results show that [AlO4]- tetrahedron acts as network formers and melt network structure is mainly chain and lamellar in the low-viscosity area. The cross sections of w(F) = 8 wt.%, w(Li2O) = 8 wt.% and w(F) = 12 wt.%, w(Li2O) = 8 wt.% are important reference sections for the design of mold flux, with the compositions of 22–40 wt.% CaO, 14–34 wt.% BaO, 20–34 wt.% Al2O3 and 23–40 wt.% CaO, 14–34 wt.% BaO, 20–28 wt.% Al2O3, respectively.
Yang Chen,Sheng-ping He,Zhi-rong Li, et al. Properties and structure of a new non-reactive mold flux for high-Al steel[J]. Journal of Iron and Steel Research International, 2022, 29(01): 61-70.