Combustion synthesis of porous β-SiAlON from aluminum ferrosilicon and aluminosilicate hollow microspheres

SiAlON ceramics is a unique material used in various applications. Producing porous SiAlON material from available industrial waste by combustion is of great interest. In this work, a porous SiAlON composite was synthesized by the combustion of a mixture of aluminum ferrosilicon powder and aluminosilicate hollow microspheres in nitrogen. Aluminosilicate hollow microspheres were used as a pore-forming agent. The addition of aluminosilicate hollow microspheres to aluminum ferrosilicon powder increased the total porosity from 34.1 to 90.3%, the open porosity from 16.4 to 88.2%, and the maximum pore size from 53 to 413 μm in the final product. The porosity of the synthesized samples was predominantly open.