The Influence of Metallic Antioxidants on some Critical Properties of Magnesia-carbon Refractories
1 CSIR-Central Glass and Ceramic Research Institute, Kolkata 700032/India
2 Rashtriya Ispat Nigam Ltd., Visakhapatnam 530031/India
Revision
Volume 5, Issue 4, Pages 69 - 74
Abstract
MgO-C refractories received great attention in steel making process during the last decade. However, the oxidation of carbon at high temperature degrades its mechanical and corrosion resistance properties. Antioxidants like metal powder and carbides suppress carbon oxidation of MgO-C brick. Judicious selection of antioxidants optimizes the properties of MgO-C refractory. In the present work the effect of Al, Si and their combination in MgO-C refractory is studied. Phase development between 1100 °C to 1500 °C was evaluated through XRD analysis. The properties of the refractory were evaluated in terms of oxidation resistance, bulk density, apparent porosity, coked CCS, hot modulus of rupture and dynamic corrosion resistance test. Combined antioxidants develop forsterite and spinel phase and suppress oxidation of carbon. Both these phases are solid soluble with each other and refractory in nature. As a result the developed MgO-C brick leads to improved hot strength and corrosion resistance.
Keywords
antioxidants, corrosion, MgO-C refractories
References
[1] Buchebner, G.; Pirker, S.: New high performance refractories for BOF vessels (in German). Veitsch-Radex Rundschau 2 (1996) 3–14 [2] Nandy, S.K.; Ghosh, N.K.: Evaluation of critical properties of MgO-C with addition of metallic. Proc. of Unified Int. Technical Conf. on Refrac - tories (2005) [3] Campos, K.S.; et al.: The influence of B4C and MgB2 additions on the behavior of MgO-C bricks. Ceram. Int. 38 (2012) [7] 5661–5667 [4] Gokce, A.S.; et al.: The effect of antioxidants on the behaviour of magnesia-carbon refractory bricks. Ceram. Int. 34 (2008) 323–330 [5] Yamaguchi, A.; Tanaka, H.: Behaviour and effects of ZrB2 added to carbon containing refractories. Taikabutsu Overseas 15 (1994) 3–9 [6] Refractories Handbook. The Technical Association of Refractories, Japan, 1998 [7] Wang, T.; Yamaguchi, A.: Oxidation protection of MgO-C refractories by means of Al8B4C7. J. Amer. Ceram. Soc. 84 (2001) 577–582 [8] Ghosh, N.K.; Jagannathan, K.P.; Ghosh, D.N.: Oxidation of magnesia-carbon refractories with addition of aluminium and silicon in air. Inter cer am 50 (2001) [11] 196–202 [9] Yamaguchi, A.: Behaviour of boron carbide added to carbon-containing refractories. Taika - butsu 36 (1984) [10] 558–563 [10] Zhang, S.; Marriott, N.J.; Lee, W.E.: Thermo - chem istry and microstructure of MgO-C refractories containing various antioxidants. J. Europ. Ceram. Soc. 21 (2001) 1037–1047 [11] Yamaguchi, A.; Zhang, S.; Yu, J.: Effect of refractory oxides on the oxidation of graphite and amorphous carbon. J. Amer. Ceram. Soc. 79 (1996) 2509–2511 [12] Aneziris, C.G.; et al.: Microstructure evaluation of MgO-C refractories with TiO2 and Al additions. J. Europ. Ceram. Soc 27 (2007) 73–78 [13] Naruse, Y.; et al.: Results of investigation of mag-carbon bricks used in converter. Taika - butsu 3 (1983) [2] 3–7 [14] Cunha-Duncan, F.N.; et al.: Synthesis of magnesium aluminate spinels from bauxites and magnesias. J. Amer. Ceram. Soc. 85 (2002) 2995–3003
Copyright
Göller Verlag GmbH