Effects of Atmospheric Conditions on Slag Corrosion Resistance of Lightweight Al₂O₃-MgO Castables

Abstract:

By adopting dynamic induction furnace corrosion test, the corrosion mechanism of lightweight Al₂O₃-MgO castable with different environmental oxygen partial pressure was investigated through macro- and micro-analysis, XRD and thermodynamic simulation. The atmospheric condition was set to P(O₂) = 0.21 atm or P(Ar) = 1.0 atm. The attained results showed that a reduced slag corrosion but intensified slag penetration happened at low environmental oxygen partial pressure condition. With P(O₂) = 0.21atm, Mn and Fe in slag were present in the form of divalent and/or trivalent cations and were incorporated into spinel to form MnFe₂O₄ solutions and MgAl₂O₄ solutions during corrosion process. Since Fe, Mn ions are largely consumed, liquid with high viscosity formed and the continuing infiltration was suppressed. Under P(Ar) =1.0 atm, corrosion on castable aggregates was significantly weakened, and the reaction products under this condition are mainly MgAl₂O₄ and CA₆.

• Periodical: Key Engineering Materials (Volume 768)
• Pages: 274-278
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.768.274
• Online since: April 2018
• Authors: Yang Zou, Hua Zhi Gu, Ao Huang
• Keywords: Atmosphere, Corundum-Spinel Castable, Lightweight, Slag Corrosion

References

[1] Hisashi T, Tomoaki T, Hidenori T. Low thermal conductivity Al2O3–MgO–C bricks for steel ladle. Taikabutsu. 2010;62(1):34-5. [In Japanese].

[2] Lyckfeldt O, Ferreira JM. Processing of porous ceramics by starch consolidation,. J EUR CERAM SOC. 1998 Jan 1;18(2):131-40.

[3] Liu R, Li Y, Wang CA, Tie S. Fabrication of porous alumina–zirconia ceramics by gel-castingand infiltration methods. MATER DESIGN. 2014 Nov 30;63:1-5.

DOI: 10.1016/j.matdes.2014.05.061

[4] Wen Y, Junfeng C, Nan L. Slag Resistances of Lightweight Corundum-Mullite Refractories. RARE METAL MAT ENG. 2015 Nov 1;44:442-6.

[5] Fu L, Gu H, Huang A, Zhang M, Hong X, Jin L. Possible improvements of alumina–magnesia castable by lightweight microporous aggregates. CERAM INT. 2015 Jan 31;41(1):1263-70.

DOI: 10.1016/j.ceramint.2014.09.056

[6] Van Ende MA, Jung IH. A kinetic ladle furnace process simulation model: effective equilibrium reaction zone model using FactSage macro processing. METALL MATER TRANS B. 2017 Feb 1;48(1):28-36.

DOI: 10.1007/s11663-016-0698-6

[7] Bannenberg N. Demands on refractory material for clean steel production. InUNITECR'95 Congress. Proc. Unified Int. Tech. Conf. on Refractories 1995 Nov (Vol. 4).

[8] Normanton A, Millman S, Ridal K. Advances in secondary steelmaking and continuous casting. IRONMAK STEELMAK. 2004 Oct 1;31(5):347-55.

DOI: 10.1179/irs.2004.31.5.347