Combustion synthesis of network silicon nitride porous ceramics

A porous silicon nitride ceramics, composed of a network interconnected β-Si3N4 rods, was prepared by using the combustion synthesis method. Si powder with more than 20 wt.% diluent α-Si3N4 was fully nitrided under high nitrogen pressure. The interconnected open porosity of the obtained combustion products was as high as 64.40%. In the combustion products, rod-like β-Si3N4 grains were formed to build up the network silicon nitride porous ceramics.