In order to achieve self-repairing of MgO-C refractory in oxidizing atmosphere at high temperatures, Fe powder, serving as both antioxidant and direct-bond former, was introduced into this refractory. The effect of Fe addition on the microstructure, properties and oxidation resistance was investigated. The coexistence of (Mg,Fe)Oss and Mg(Fe1.2Al0.8)O4 was identified for the Fe-containing MgO-C refractory after graphite was oxidized, by which a network was formed in the matrix. As a consequence, both densification and direct-bond in the oxidized layer were greatly enhanced compared with the conventional MgO-C refractory, solving the issue of strength degradation during high temperature oxidation. An excellent oxidation resistance was obtained owing to the above improvements.

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