Progress in Preparation and Properties of Porous Silicon Nitride Ceramics

Porous silicon nitride ceramics is a promising functional ceramic material. In recent years, the research on the preparation of porous silicon nitride ceramics within different methods has been widely investigated. First, this work reviews the main synthesis methods of Si 3 N 4 porous ceramics in detail, and compares the differences between strength and porosity caused by each method. The characteristics and advantages of different technologies under the current conditions were evaluated. Second, the dielectric properties, sound absorption properties and permeability properties of silicon nitride ceramics were compared and summarized based on the experimental results. Third, the applications fields of porous silicon nitride ceramics, such as smelting industry, catalyst carrier, sound absorption, wave-transparent, and biomedical fields were explored. Finally, the assessment of different silicon nitride ceramics preparation technologies was elaborated. This review gives an outlook on the porous silicon nitride ceramics, which shows great potential for further research in this field.