# Low Expansion Glass-Ceramic

Low expansion glass-ceramic is a glass-type material. The graph bars on the material properties cards below compare low expansion glass-ceramic to other glass and glass-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

Elastic (Young's, Tensile) Modulus

83 *GPa* 12 *x 10 ^{6} psi*

Flexural Strength

35 *MPa* 5.1 *x 10 ^{3} psi*

Knoop Hardness

530

Poisson's Ratio

0.22

Tensile Strength: Ultimate (UTS)

53 *MPa* 7.7 *x 10 ^{3} psi*

## Thermal Properties

Maximum Temperature: Mechanical

690 *°C* 1270 *°F*

Specific Heat Capacity

800 *J/kg-K* 0.19 *BTU/lb-°F*

Thermal Conductivity

1.5 *W/m-K* 0.86 *BTU/h-ft-°F*

Thermal Expansion

1.7 *µm/m-K*

## Electrical Properties

Dielectric Constant (Relative Permittivity) At 1 MHz

5.7

Electrical Resistivity Order of Magnitude

11 *10 ^{x} Ω-m*

## Otherwise Unclassified Properties

Density

2.4 *g/cm ^{3}* 150

*lb/ft*

^{3}Light Transmission Range

0.5 to 2.7 *µm*

Refractive Index

1.5

## Common Calculations

Stiffness to Weight: Axial

19 *points*

Stiffness to Weight: Bending

59 *points*

Strength to Weight: Axial

6.1 *points*

Strength to Weight: Bending

13 *points*

Thermal Diffusivity

0.76 *m ^{2}/s*

Thermal Shock Resistance

28 *points*

## Followup Questions

## Further Reading

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