Preparation of single-phase magnesium silicon nitride powder by a two-step process

Single-phase magnesium silicon nitride (MgSiN2) powder was prepared by a two-step process: combustion synthesis followed by acid washing. The effects of starting material compositions, diluent addition and N2 pressure on the phase compositions of the final products were studied, and the acid washing process was also discussed. It is difficult to synthesize single-phase MgSiN2 by one-stage combustion reaction through regulating the process parameters because of the evaporative loss of Mg. Combustion synthesis of MgSiN2 by using an excess of magnesium in the starting materials and then acid washing off the impurity was an effective way to prepare the single-phase MgSiN2 powder.