Pure alumina (Al₂O₃) and carbon‐bonded alumina (Al₂O₃−C) are used to investigate their interaction with iron (Armco) at 1625 °C, applying the sessile drop method. The investigations are conducted inside a heating microscope for 1 h under argon atmosphere with low oxygen partial pressure. No whiskers formation is observed from the experiments with pure Al₂O₃ and molten iron. In the case of Al₂O₃−C/Fe system, several phenomena including the decarburization of Al₂O₃−C, Al₂O₃−C dissolution in molten iron, Al₂O₃ layer formation on the iron droplet, and Al₂O₃ whiskers formation are observed. To clarify the possible influence of iron on Al₂O₃ whiskers formation, blank Al₂O₃−C samples without the presence of iron are heated and held in a half‐sealed platinum crucible at 1550 °C for 2 h. Thereby, the Al₂O₃ whiskers formation is detected. Finally, the experimental investigations are supported with thermodynamic simulations.

The thermophysical properties (viscosity, density, and surface tension) of the secondary metallurgical slags with various CaO/Al₂O₃ ratios (0.56–1.99) and SiO₂ (1–20 wt%) contents are investigated. The results show that the addition of SiO₂ increases the viscosity of the cleanness and desulfurization slags (CaO/Al₂O₃ ratios ≥1). In slag with a higher Al₂O₃ content (CaO/Al₂O₃ < 1) and constant CaO content, the viscosity shows a first decreased and then increased phenomenon with the addition of SiO₂. Moreover, the breakpoints of the viscosity are strongly lowered with the addition of SiO₂. Both the density and surface tension of slags show a decreasing tendency with the SiO₂ addition. Moreover, the single hot thermocouple technique method is applied to investigate the crystallization process of the slags, and the result shows that with high SiO₂ contents, glassy layers are formed on the molten slags.

The current investigation delves into the oxidation resistance of magnesia‐carbon‐bonded (MgO‐C) refractory enhanced with calcium magnesium aluminate (CMA) cement, metallic aluminum, and Carbores P across a broad temperature spectrum from 800 to 1600 °C. The results demonstrate that the modification with CMA up to a temperature threshold of 1200 °C does not compromise the material's inherent oxidation resistance. However, above this temperature, a decrement in oxidation resistance is observed. The impact of grain size variation in CMA on the oxidation resistance of MgO‐C refractories is notable, and the finer grains show a superior performance. MgO‐C sample with Carbores P has excellent oxidation resistance up to 1000 °C, while above 1200 °C, its oxidation resistance strongly deteriorates. The metallic aluminum addition exhibits a remarkable oxidation resistance throughout the evaluated temperature range, indicated by a slight oxidation.