Zirconia Toughened Alumina (ZTA)
Typically made up of >80% Al2O3 and the rest Y-TZP. ZTA can provide some of the advantages of Y-TZP at a reduced price due to the predominant alumina content.
The alumina is strengthened by a mechanism known as stress induced transformation toughening. When a crack forms in the material the zirconia in the region transforms from a metastable tetragonal phase to a stable monoclinic phase. This change causes an increase in volume leading to compressive stresses in the alumina matrix. These stresses close the crack and prevent further cracking, The addition of the zirconia increases the fracture toughness and strength of the alumina greatly.
ZTA has good mechanical strength, fracture toughness and impact resistance which means it finds application in ballistics and wear applications.
- Good mechanical strength
- Good fracture toughness
- Good impact resistance
- High dielectric strength
- Pump components
- Cutting tool inserts