2008 Volume 48 Issue 6 Pages 760-767
Corrosion of MgO–C refractories in different gas atmospheres consisting of air, Ar, CO or Ar/CO was studied in laboratory experiments. In total, 103 experiments were carried out in the temperature range 1173 to 1773 K and for holding times between 2 to 120 min. The reaction rate of the MgO–C material was determined from measurements of the weight loss of the samples. The results showed that the refractory weight loss increased with an increased temperature or an increased holding time. The thermodynamic conditions and the experimental results showed that magnesium gas and carbon monoxide gas should form during ladle refining of steel when the refractory material consists of MgO–C. It was suggested that the reaction rate is directly dependent on the oxygen potential in the ambient atmosphere.