Zirconia

Zirconium dioxide is a versatile material used in a broad range of applications from metal casting to dental implants. At room temperature ZrO2 exhibits a monoclinic crystal structure. It transitions to tetragonal and cubic when fired at higher temperatures. This can cause cracking during heating and cooling cycles, stresses often occurring during the cooling cycle. When zirconia is mixed with a small amount of some other types of oxides, the tetragonal and/or cubic phases are stabilized. Oxides that work well for this purpose include magnesium oxide (MgO), yttrium oxide (Y2O3, yttria), calcium oxide (CaO), and cerium(III) oxide (Ce2O3).