NEMA Grade FR-4 (GEE-F) Glass-Epoxy Laminate
NEMA grade FR-4 is a grade of NEMA laminate. The graph bars on the material properties cards below compare NEMA grade FR-4 to other thermoset plastics (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
330 MPa 47 x 103 psi
Flexural Modulus
17 GPa 2.5 x 106 psi
Flexural Strength
340 MPa 50 x 103 psi
Impact Strength: Notched Izod
330 J/m 6.3 ft-lb/in
Rockwell M Hardness
110
Shear Strength
130 MPa 19 x 103 psi
Tensile Strength: Ultimate (UTS)
260 MPa 37 x 103 psi
Thermal Properties
Maximum Temperature: Mechanical
140 °C 280 °F
Thermal Expansion
10 µm/m-K
Electrical Properties
Dielectric Constant (Relative Permittivity) At 1 MHz
4.6
Dielectric Strength (Breakdown Potential)
18 kV/mm 0.7 V/mil
Otherwise Unclassified Properties
Density
1.9 g/cm3 120 lb/ft3
Water Absorption After 24 Hours
0.17 %
Common Calculations
Strength to Weight: Axial
39 points
Strength to Weight: Bending
49 points
Followup Questions
Further Reading
NEMA LI 1: Industrial Laminated Thermosetting Products
Thermosets: Structure, Properties and Applications, Qipeng Guo (editor), 2012