Low-temperature preparation of Si3N4/SiC porous ceramics via foam-gelcasting and microwave-assisted catalytic nitridation

Si3N4/SiC porous ceramics were fabricated by a novel foam-gelcasting and microwave-assisted catalytic nitridation method at a temperature as low as 1273 K for 60 min or after only 10 min at 1373 K utilizing commercial Si and SiC with trace of impurity Fe (0.33 wt%) as starting materials. The Si3N4/SiC porous ceramics containing porosity of 68.54 ± 0.73% which were fabricated at 1373 K for 10 min had flexural and compressive strengths of 5.28 ± 0.17 MPa and 12.86 ± 1.55 MPa.