Unfilled POM-H
Unfilled POM-H is a grade of POM-H. The graph bars on the material properties cards below compare unfilled POM-H to: polyoxymethylene plastics (top), all thermoplastics (middle), 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
3.4 GPa 0.49 x 106 psi
Elongation at Break
55 %
Fatigue Strength
29 MPa 4.3 x 103 psi
Flexural Modulus
2.9 GPa 0.42 x 106 psi
Flexural Strength
94 MPa 14 x 103 psi
Impact Strength: Notched Izod
75 J/m 1.4 ft-lb/in
Rockwell M Hardness
94
Tensile Strength: Ultimate (UTS)
67 MPa 9.7 x 103 psi
Thermal Properties
Glass Transition Temperature
-23 °C -8.5 °F
Heat Deflection Temperature At 1.82 MPa (264 psi)
130 °C 270 °F
Heat Deflection Temperature At 455 kPa (66 psi)
160 °C 320 °F
Maximum Temperature: Autoignition
350 °C 650 °F
Maximum Temperature: Decomposition
330 °C 620 °F
Maximum Temperature: Mechanical
90 °C 190 °F
Melting Onset (Solidus)
180 °C 360 °F
Specific Heat Capacity
1460 J/kg-K 0.35 BTU/lb-°F
Thermal Conductivity
0.33 W/m-K 0.19 BTU/h-ft-°F
Thermal Expansion
120 µm/m-K
Vicat Softening Temperature
170 °C 330 °F
Electrical Properties
Dielectric Constant (Relative Permittivity) At 1 Hz
3.7
Dielectric Strength (Breakdown Potential)
58 kV/mm 2.3 V/mil
Electrical Dissipation At 1 MHz
0.0050
Electrical Resistivity Order of Magnitude
13 10x Ω-m
Otherwise Unclassified Properties
Density
1.4 g/cm3 89 lb/ft3
Limiting Oxygen Index (LOI)
15 %
Water Absorption After 24 Hours
0.25 %
Common Calculations
Stiffness to Weight: Axial
1.3 points
Stiffness to Weight: Bending
35 points
Strength to Weight: Axial
13 points
Strength to Weight: Bending
26 points
Thermal Diffusivity
0.16 mm2/s
Thermal Shock Resistance
12 points
Followup Questions
Further Reading
SPI Plastics Engineering Handbook of the Society of the Plastics Industry, Inc., 5th ed., Michael L. Berins (editor), 2000
Modern Plastics Handbook, Charles A. Harper (editor), 1999
Plastics Materials, 7th ed., J. A. Brydson, 1999
CRC Materials Science and Engineering Handbook, 4th ed., James F. Shackelford et al. (editors), 2015