Zirconia (Zirconium Dioxide, ZrO2)
Zirconia is an oxide-based engineering ceramic. It can have a moderately high tensile strength among oxide-based engineering ceramics. In addition, it can have a fairly high density and a moderately low heat capacity.
The properties of zirconia include three common variations. This page shows summary ranges across all of them. For more specific values, follow the links immediately below. The graph bars on the material properties cards further below compare zirconia to other oxide-based engineering ceramics (top) and the entire database (bottom). A full bar means this is the highest value in the relevant set. A half-full bar means it's 50% of the highest, and so on.
Mechanical Properties
Compressive (Crushing) Strength
1260 to 3080 MPa 180 to 450 x 103 psi
Elastic (Young's, Tensile) Modulus
190 to 200 GPa 28 to 29 x 106 psi
Flexural Strength
630 to 970 MPa 91 to 140 x 103 psi
Fracture Toughness
8.0 to 11 MPa-m1/2 7.3 to 9.9 x 103 psi-in1/2
Knoop Hardness
1210 to 1300
Poisson's Ratio
0.25 to 0.29
Tensile Strength: Ultimate (UTS)
410 to 450 MPa 60 to 65 x 103 psi
Thermal Properties
Maximum Temperature: Mechanical
500 to 1330 °C 930 to 2430 °F
Maximum Thermal Shock
300 to 350 °C 570 to 660 °F
Specific Heat Capacity
400 to 510 J/kg-K 0.1 to 0.12 BTU/lb-°F
Thermal Conductivity
2.2 to 4.3 W/m-K 1.2 to 2.5 BTU/h-ft-°F
Thermal Expansion
8.8 to 9.5 µm/m-K
Other Material Properties
Density
5.7 to 6.0 g/cm3 350 to 370 lb/ft3
Dielectric Constant (Relative Permittivity) At 1 MHz
28
Dielectric Strength (Breakdown Potential)
7.7 to 9.0 kV/mm 0.3 to 0.35 V/mil
Electrical Resistivity Order of Magnitude
4.5 to 11 10x Ω-m
Common Calculations
Stiffness to Weight: Axial
19 points
Stiffness to Weight: Bending
33 to 34 points
Strength to Weight: Axial
19 to 22 points
Strength to Weight: Bending
21 to 23 points
Thermal Diffusivity
0.73 to 1.8 mm2/s
Thermal Shock Resistance
15 to 19 points
Followup Questions
Further Reading
Ceramic and Glass Materials: Structure, Properties and Processing, James F. Shackelford and Robert H. Doremus (editors), 2008
Ceramics and Composites: Processing Methods, Narottam P. Bansal and Aldo R. Boccaccini (editors), 2012
Springer Handbook of Condensed Matter and Materials Data, W. Martienssen and H. Warlimont (editors), 2005