Degradation Behavior of MgO-C Refractory in Contact With Molten Iron: With/Without Ar Blowing

High carbon MgO-C refractories with thermal shock resistance of carbon are used as the bottom blowing material in contact with molten iron in converter, electric arc furnace.1-3 However, MgO-C refractories have some drawbacks at iron & steelmaking environment. Carbon is vulnerable to an oxygen atmosphere4, can be dissolved into molten iron.5 MgO-C refractories also degraded itself by the reduction reaction of MgO by C at a high temperature and it increased with temperature.6 Such degraded refractories are easily damaged by impact and lowered lifetime.7 Some researchers studied that the reactions between MgO-C refractories and molten iron.8,9 The formation of the oxide layer or inclusions by components and impurities in refractory were observed at the molten iron/refractory interface.