Mica-Containing Glass-Ceramic (IEC 60672 Type GM-120)
GM-120 glass ceramic is a glass-type material. It has a moderately low dielectric strength among the glass and glass-ceramics in the database. The graph bars on the material properties cards below compare GM-120 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.
Thermal Properties
Maximum Thermal Shock
110 °C 230 °F
Thermal Conductivity
3.0 W/m-K 1.7 BTU/h-ft-°F
Thermal Expansion
9.5 µm/m-K
Electrical Properties
Dielectric Strength (Breakdown Potential)
11 kV/mm 0.45 V/mil
Electrical Resistivity Order of Magnitude
10 10x Ω-m
Other Material Properties
Density
2.5 g/cm3 150 lb/ft3
Elastic (Young's, Tensile) Modulus
56 GPa 8.1 x 106 psi
Flexural Strength
57 MPa 8.3 x 103 psi
Common Calculations
Stiffness to Weight: Axial
13 points
Stiffness to Weight: Bending
52 points
Followup Questions
Further Reading
IEC 60672-3: Ceramic and glass-insulating materials - Part 3: Specifications for individual materials
CRC Materials Science and Engineering Handbook, 4th ed., James F. Shackelford et al. (editors), 2015