Properties of a reaction-bonded β-SiAlON ceramic doped with an FeMo alloy for application to molten aluminum environments

An FeMo-alloy-doped β-SiAlON (FeMo/β-SiAlON) composite was fabricated via a reaction-bonding method using raw materials of Si, Al₂O₃, AlN, FeMo, and Sm₂O₃. The effects of FeMo on the microstructure and mechanical properties of the composite were investigated. Some properties of the composite, including its bending strength at 700°C and after oxidization at 700°C for 24 h in air, thermal shock resistance and corrosion resistance to molten aluminum, were also evaluated. The results show that the density, toughness, bending strength, and thermal shock resistance of the composite are obviously improved with the addition of an FeMo alloy. In addition, other properties of the composite such as its high-temperature strength and oxidized strength are also improved by the addition of FeMo alloy, and its corrosion resistance to molten aluminum is maintained. These findings indicate that the developed FeMo/β-SiAlON composite exhibits strong potential for application to molten aluminum environments.