Strategies to improve oxidation resistance of MgO–C refractories by decreasing oxygen potential through MgSiN2

Abstract MgO–C refractories are of paramount importance in the converter side blowing system, requiring outstanding oxidation resistance under harsh conditions including high temperature, oxygen atmosphere, and high‐speed airflow. In this study, MgSiN 2 phase reconstruction was used to improve the oxidation resistance of MgO–C refractories, as well as the mechanical properties and oxidation resistance of MgO–C refractories were evaluated. The results indicated that the cold modulus of rupture of the sample with 9 wt% MgSiN 2 was increased by 93.3% compared with the MgO–C refractories without MgSiN 2 . After oxidation tests, the oxidation index and rate constant ( k ) of the sample with 9 wt% MgSiN 2 were reduced by 38.9% and 35.3%. Furthermore, incorporating MgSiN 2 facilitated the formation of layered dense structures consisting of plate‐like Mg‐Sialon and MgO–Mg 2 SiO 4 –MgAl 2 O 4 . This structural optimization effectively inhibited oxygen diffusion and reaction within the material, resulting in gradual oxygen potential mitigation.