ZTA (Zirconia Toughened Alumina) is a composite material made from alumina and zirconia. It combines the outstanding characteristics of both materials.
Compared to conventional alumina, ZTA possesses superior hardness, higher flexural strength, and similar density. Compared to conventional zirconia, it possesses a lower coefficient of linear thermal expansion and higher thermal conductivity.
By leveraging these features, ZTA has been widely adopted in milling parts and wear-resistant parts that require cooling.

ZTA (Zirconia Toughened Alumina)
Features:
- High Stiffness and Outstanding Wear Resistance
- Stiffer than alumina with outstanding wear resistance equivalent to zirconia.
- High Thermal Conductivity and Low Thermal Expansion
- Suppresses thermal deformation through thermal conductivity and low thermal expansion equivalent to alumina. Suitable for components requiring a cooling Mechanism.
- High Strength and Specific Rigidity
- Approximately twice as strong as alumina and contributes to low-weight design through high specific rigidity.
Below is the material properties for ZTA:
Properties |
Unit |
ZTA ceramic |
|
Zirconia Content | % | 20% | |
Color | white | ||
Volume density |
g /cm3 |
4.1 | |
Water Absorption | % | 0 | |
Crystal Size(Grain Size) | μm | 5-6 | |
Vickers Hardness, HV1.0 | Gpa | ≥15 | |
Flexural Strength | Mpa | ≥500 | |
Coefficient of linear expansion | 20-500℃ | 1×10-6mm/℃ | 6.5~7.5 |
20-800℃ | 6.5~8.0 | ||
Thermal conductivity | W/m·K( 20℃) | ≥20.9 | |
Specific Heat Capacity | KJ/(kg*K) | ≥0.8 | |
Dielectric Strength | KV/mm | ≥9 | |
Volume resistivity | Ω·cm 20℃ | ≥1014 | |
Ω·cm 300℃ | ≥1011 | ||
Ω·cm 500℃ | ≥109 | ||
Dielectric Constant | 1MHz | 9-10 | |
Tangent Of Dielectric Loss | 1MHz | ≤5×10-4 | |
Surface Roughness | μm | 0.1-0.4 after the machine |