# Beryllia (Beryllium Oxide, BeO)

Beryllia is an oxide-based engineering ceramic. It has a fairly high heat capacity and the highest thermal conductivity among oxide-based engineering ceramics. The graph bars on the material properties cards below compare beryllia 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

1650 *MPa* 240 *x 10 ^{3} psi*

Elastic (Young's, Tensile) Modulus

350 *GPa* 50 *x 10 ^{6} psi*

Flexural Strength

240 *MPa* 35 *x 10 ^{3} psi*

Poisson's Ratio

0.26

Shear Modulus

180 *GPa* 25 *x 10 ^{6} psi*

Tensile Strength: Ultimate (UTS)

140 *MPa* 20 *x 10 ^{3} psi*

## Electrical Properties

Dielectric Constant (Relative Permittivity) At 1 MHz

6.6

Dielectric Strength (Breakdown Potential)

11 *kV/mm* 0.45 *V/mil*

Electrical Dissipation At 1 MHz

0.00060

Electrical Resistivity Order of Magnitude

13 *10 ^{x} Ω-m*

## Other Material Properties

Density

2.9 *g/cm ^{3}* 180

*lb/ft*

^{3}Maximum Temperature: Mechanical

1750 *°C* 3180 *°F*

Specific Heat Capacity

1050 *J/kg-K* 0.25 *BTU/lb-°F*

Thermal Conductivity

270 *W/m-K* 150 *BTU/h-ft-°F*

Thermal Expansion

8.0 *µm/m-K*

## Common Calculations

Stiffness to Weight: Axial

67 *points*

Stiffness to Weight: Bending

82 *points*

Strength to Weight: Axial

14 *points*

Strength to Weight: Bending

21 *points*

Thermal Diffusivity

89 *mm ^{2}/s*

Thermal Shock Resistance

3.6 *points*

## Followup Questions

## Further Reading

ASTM C242: Standard Terminology of Ceramic Whitewares and Related Products

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

CRC Materials Science and Engineering Handbook, 4th ed., James F. Shackelford et al. (editors), 2015