Study on the Properties and Microstructure of Mullite-Fe₂O₃ Composite

Abstract

Regarded as an important structural and functional material, mullite is widely researched on electronic, optical and high-temperature structural applications. In this paper, dense 70mol% mullite- 30mol% α- Fe₂O₃ composite has been obtained at 1450^oC in air by pressureless sintering technique. Due to the excess of solid solution limitation under sintering temperature, iron oxide is well dispersed as a secondary phase in the mullite- Fe ₂ O ₃ solid solution matrix, which is confirmed by phase and microstructure analysis. The mechanical, magnetic and high temperature electric conductive properties of the composite were measured. It is shown that the mechanical properties of composite are comparable with those of monothetic mullite. Furthermore, the composite also behaves ferromagnetic property in room temperature and good electric conductivity in high temperature, which shows the possibility of adding multiple functions to mullite composite.