YTZP Zirconia exists in three different phases: monoclinic, tetragonal, and cubic. YTZP is produced almost entirely as crystalline tetragonal zirconia by incorporating about 3 mol percent yttria, or about 5 weight percent. Using yttria as the stabilizer allows tetragonal to remain as a metastable phase at room temperature. This metastable phase creates a transformation toughened material when stresses cause the tetragonal grains to convert into larger monoclinic grains. The localized volume increase effectively mitigates destructive cracks from propagating.
HIPed YTZP has excellent flexural strength of 1500 MPa, which is 4 times stronger than alumina and sintered silicon carbide, 3 times stronger than most magnesia stabilized zirconias and 5 times stronger than steel.
Its excellent strength, hardness, abrasion and corrosion resistance make YTZP ideal for tough applications operating at up to 850ºC. When HIPed it has a near perfect fine-grained microstructure (grains <0.5µm) that can be machined and polished into sharp blades and knives, plungers and liners for pumps, paint mandrels and necking dies for making cans and even a replacement tooth