Phase evolution of Al–Al2O3–ZrO2 refractories at 1300 °C under N2 flowing

In order to obtain Al–Al 2 O 3 –ZrO 2 composite refractories with excellent oxidation resistance, erosion resistance and thermal shock stability, metallic aluminium and fused Al 2 O 3 –ZrO 2 were used as the raw materials, while phenolic resin was used as the binding agent. The microstructure was characterised by means of X-ray diffraction and scanning electron microscopy tests. Based on the reaction between zirconia and metallic aluminium under N 2 flowing at 1300 °C, the reaction mechanism of zirconia and metallic aluminium in-situ reaction at 1300 °C to generate (Al 2 OC) x (AlN) 1− x solid solution, zirconium nitride, and aluminium–zirconium alloy was revealed, and a model for the evolution of the phases in the aluminium-added Al–Al 2 O 3 –ZrO 2 specimen was constructed to realise the Al–Al 2 O 3 –ZrO 2 composite refractories phase controlling. Based on the good corrosion resistance of ZrO 2 to CaO and the excellent results of the in-situ reaction of metallic aluminium to generate a large number of non-oxide reinforcing phases capable of replacing elemental C, this work is of great significance for the study of refractory in erosion-heavy environments, such as calcium-treated steel.