Abstract: MgO-Al2O3-C refractories were prepared with fused magnesia，used MC brick，α-Al2O3 and graphite as raw materials，with BN/ZrB2 as the compound additive，through the process of co-grinding，mixing with phenolic resin as the bonder，forming and heat treatment.The effects of BN/ZrB2 additive and sintering temperature on the sintering property， oxidation resistance，microstructure，and mineral composition of the sintered specimens were investigated.Results indicated that the preferential oxidation，in the MgO-Al2O3-C refractories with BN/ZrB2 as the compound additive，was ordered by ZrB2>BN>C，and BN/ZrB2 was oxidated to B2O3.It was shown that Mg3B2O6 with low melting point was generated with B2O3 reacted with MgO from fused magnesia and used magnesia-carbon brick in the experiment.The sintering property and oxidation resistance of MgO-Al2O3-C refractories were contributed by the liquid Mg3B2O6 generation.The mineral composition included periclase，MA spinel and a small amount of Mg3B2O6.

Key words: BN/ZrB2, MgO-Al2O3-C, sintering property, oxidation resistanc