Lattice variations and phase evolutions during combustion reactions in Mo-Si-Al system

Combustion synthesis technique was used to alloy MoSi2 with Al. The added Al in the starting powder mixtures were changed in the range of 0.0-17.867 wt%. It was demonstrated that Al additions, decreases the ignition temperature and helps the exothermicity of the reaction. Increasing of incorporated Al also alters the crystal structure of MoSi2 from tetragonal C11b to hexagonal C40 and further to orthorhombic C54. It was also shown that any increase in Al additions, generally leads to a continuous lattice expansion in the mentioned structures.