Effect of NaN3 Addition Content on NaCl-NaF Medium Nitridation Synthesis β-Sialon Powders

β-Sialon powders were synthesized via salt-assisted nitridation synthesis from Al, Si, SiO2 powders and molten salt medium (NaCl and NaF) with the addition of different content of NaN3 at different temperature for 3 h. NaN3 were employed as auxiliary nitrogen source which effectively provide sufficient nitrogen. The results indicated that the growth of β-Sialon powders had better effect when the NaN3 was added. And the β-Sialon powders grew more completely and the morphology of β-Sialon powders showed the rod-like crystal with hexagonal smooth tips instead of conical tips. In addition, the products displayed different sizes when the content of NaN3 was changed. These results of this work suggested that β-Sialon could be synthesized with specific morphology by adding different content of NaN3.