| Abstract: | Si_2N_2O ceramics were prepared using amorphous Si_3N_4 as the raw material and Li2_CO_3 as the sintering additive through vacuum multi-stage sintering. The influence of the Li2_CO_3 addition(0%, 1%, 2%, 3%, and 5%, by mass) on the phase composition, the microstructure, the porosity, the mechanical properties, the dielectric constant and the tangent of the dielectric loss angle of the porous Si_2N_2O ceramics was investigated. The results reveal that a suitable addition of Li2_CO_3 can promote the generation of Si_2N_2O but excessive or inadequate Li2_CO_3 causes decomposition of Si_2N_2O ceramics. The prepared porous Si_2N_2O ceramics have good mechanical properties, good thermal shock resistance, and low dielectric properties, which have excellent potential for application in microwave sintering furnaces. |
