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
Volume 5, Issue 4, Pages 69 - 74
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.
antioxidants, corrosion, MgO-C refractories
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