# Dense Celsian Porcelain (IEC 60672 Type C-420)

C-420 celsian porcelain is a grade of engineering porcelain. The graph bars on the material properties cards below compare C-420 celsian porcelain 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

590 *MPa* 86 *x 10 ^{3} psi*

Elastic (Young's, Tensile) Modulus

87 *GPa* 13 *x 10 ^{6} psi*

Flexural Strength

91 *MPa* 13 *x 10 ^{3} psi*

Fracture Toughness

2.0 *MPa-m ^{1/2}* 1.8

*x 10*

^{3}psi-in^{1/2}Knoop Hardness

600

Poisson's Ratio

0.17

Rockwell R Hardness

60

Shear Modulus

34 *GPa* 4.9 *x 10 ^{6} psi*

Tensile Strength: Ultimate (UTS)

130 *MPa* 19 *x 10 ^{3} psi*

## Electrical Properties

Dielectric Constant (Relative Permittivity) At 1 Hz

7.0

Dielectric Constant (Relative Permittivity) At 1 MHz

6.5

Dielectric Strength (Breakdown Potential)

23 *kV/mm* 0.89 *V/mil*

Electrical Dissipation At 1 Hz

0.0096

Electrical Dissipation At 1 MHz

0.00043

Electrical Resistivity Order of Magnitude

12 *10 ^{x} Ω-m*

## Other Material Properties

Density

3.0 *g/cm ^{3}* 190

*lb/ft*

^{3}Maximum Temperature: Mechanical

1170 *°C* 2130 *°F*

Maximum Thermal Shock

220 *°C* 440 *°F*

Specific Heat Capacity

900 *J/kg-K* 0.21 *BTU/lb-°F*

Thermal Conductivity

2.0 *W/m-K* 1.2 *BTU/h-ft-°F*

Thermal Expansion

4.6 *µm/m-K*

## Common Calculations

Stiffness to Weight: Axial

16 *points*

Stiffness to Weight: Bending

49 *points*

Strength to Weight: Axial

12 *points*

Strength to Weight: Bending

19 *points*

Thermal Diffusivity

0.73 *mm ^{2}/s*

Thermal Shock Resistance

23 *points*

## Followup Questions

## Further Reading

ASTM C242: Standard Terminology of Ceramic Whitewares and Related Products

IEC 60672-3: Ceramic and glass-insulating materials - Part 3: Specifications for individual materials

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