Microstructure and properties of an MoSi_2 heating element modified by ceramic compound

An MoSi₂ heating element was prepared by powder metallurgy with MoSi₂ powder synthesized by self-propagating high temperature synthesis (SHS) and ceramic compound as the starting materials. Its microstructure and properties were tested by XRD and SEM with EDS. The results indicated that MoSi₂ was the major phase accompanied by small fraction of Mo₅Si₃ and ceramic compound. Adding ceramic compound could obviously activate the sintering of MoSi₂ and reduce its sintering temperature and retard the over growth of grains. The hardness and fracture toughness were also improved. A glass scale with high content SiO₂ and less MgO, CaO, Na₂O, Al₂O₃ was produced by oxidation at high temperature of electric current.