What are silicon nitride ceramics?

Silicon nitride is a group of advanced engineering ceramic plates with high strength, fracture toughness, hardness, wear resistance and good chemical and thermal stability. Due to their excellent combination of properties, silicon nitride ceramic substrates are used in various structural applications, as well as electronic and industrial applications. Silicon nitride is a polycrystalline composite material consisting of silicon nitride grains (single crystals) embedded in an amorphous or partially crystalline glass phase matrix.

Silicon nitride components can be produced in dense form from powder by conventional sintering or hot pressing routes. However, an interesting and important feature of the material is that lower density (2300~2700kgm-) components can be directly produced by the nitridation of compacted silicon powder - reaction-bonding or (reaction-sintering) route. But this has the additional advantage that only slight overall volume changes occur during the manufacturing process, so complex, precisely sized shapes can be produced from the formed silicon powder blank in one stage.