The main raw materials of cordierite ceramics are talc, clay, alumina, feldspar, etc. Chlorite, magnesium carbonate, barium carbonate, zirconium silicate, zirconia, spodumene are often used as additives to reduce the sintering temperature, expand the range of sintering temperature and improve the dielectric properties.
Mullite ceramics refer to ceramics whose main crystalline phase is mullite. Mullite ceramics are made of aluminosilicate natural minerals as the main raw materials by the reaction sintering method of Mullitization in the sintering process or by the method of synthesizing mullite first, then forming and sintering.