A Comparative study of the Effect of Adding Iron and Zirconium Oxide Nanoparticles on Microstructure and Properties of MgO-CaO Refractories

The use of magnesia-doloma refractories is restricted due to their poor hydration resistance in variety industrial applications. In this investigation the effect of nano-Fe2O3 and nano-ZrO2 addition on the microstructure and hydration resistance of magnesia-doloma refractories was investigated. SEM and XRD analysis were used to investigate the microstructure and phases. Results show that the using nano-Fe2O3 causes the formation of low melting phases such as C2F, C3A and CAF surrounding CaO, MgO grains and grain boundaries at the working temperature which increased the hydration resistance, density, and decreased the porosity. Using nano-ZrO2 led to the formation of CaZrO3 phase in solid state at the working temperature which increased the hydration resistance. The results also show that the samples containing nano-ZrO2 have high hydration resistance compared to samples with nano-Fe2O3. The MC35F4Z2 sample, showed the highest hydration resistance than all nano-Fe2O3 samples and samples which contained 2, 4 and 6 wt. % nano-ZrO2.