Abstract: La₂O₃-doped MoSi₂ was synthesized by self-propagating high-temperature synthesis. The morphology
of the combustion product was investigated by using scanning electron microscopy. The fracture toughness at room temperature was measured by Anstis’ mode
and the responded microstructure was analyzed by using SEM. The results show that the addition of La₂O₃ as a doping agent significantly
influences the thermodynamics and kinetics of combustion process when compared with the combustion synthesis of molybdenum disilicide alone.
The addition of La₂O₃ can obviously decrease the particle size of the combustion product, and the addition of La₂O₃ can obviously toughen the matrix.

Key words: La₂O₃-doped MoSi₂, combustion temperature, combustion velocity, grain size, fracture toughness