Zirconium ceramics are white in color and yellow or gray when containing impurities. They generally contain HfO2 and are not easily separated. There are three crystal states of pure ZrO2 under normal pressure. The production of Zirconia Ceramics
requires the preparation of powders with high purity, good dispersion, ultrafine particles and narrow particle size distribution. There are many preparation methods for zirconia ultrafine powders. The purification of zirconia mainly includes chlorination and thermal decomposition, and alkali metals. Oxidative decomposition method, lime melting method, plasma arc method, precipitation method, colloid method, hydrolysis method, spray pyrolysis method, and the like.