Phenolic Foam vs PMI Foam
Polymer · grade comparison
Phenolic Foam and PMI Foam are both polymer grades. PMI Foam is the stronger of the two: tensile strength 2 MPa (0.319 ksi) against 0.15 MPa (0.0218 ksi) for Phenolic Foam, about 15 times as much. PMI Foam is the more ductile: elongation 3% versus 2% for Phenolic Foam. Phenolic Foam is lighter (0.05 g/cm³ vs 0.08 g/cm³ for PMI Foam) and PMI Foam is stiffer (0.09 GPa vs 0.01 GPa). On the shop floor, Phenolic Foam sits in a lower cost tier (standard, $$) than PMI Foam (high, $$$$).
Phenolic FoamChoose it when weight is the constraint, or when cost is the deciding factor.
PMI FoamChoose it when strength drives the design, or when the part is bent, formed or impact-loaded.
Phenolic Foam vs PMI Foam: propertiesHow to read these bars
- One bar per material. A full bar is the highest value among all polymer grades in the FabDigit library; each bar is drawn as a share of that.
- The better value (by the usual engineering direction) is in bold. Rows with no direction — density, thermal conductivity — have no bold.
- Values are typical room-temperature figures for the condition named on each card.
- Confirm against the certified mill or resin datasheet before design release.
How to read these bars
- One bar per material. A full bar is the highest value among all polymer grades in the FabDigit library; each bar is drawn as a share of that.
- The better value (by the usual engineering direction) is in bold. Rows with no direction — density, thermal conductivity — have no bold.
- Values are typical room-temperature figures for the condition named on each card.
- Confirm against the certified mill or resin datasheet before design release.
Mechanical
Strength, stiffness, ductility and hardness at room temperature.
Elastic (Young's) Modulus
Poisson's Ratio
Tensile Strength (Ultimate)
Elongation at Break
Compressive Strength
Compressive Modulus
Flexural Strength
Flexural Modulus
Shear Strength
Shear Modulus
Physical
Density and transition temperatures.
Density
Water Absorption (24 h)
Water Absorption (Saturation)
Glass Transition (Tg)
Thermal
How each material carries heat and how hot it can run.
Thermal Conductivity
Specific Heat Capacity
Thermal Expansion (CTE, 20–100 °C)
Max Service Temperature (continuous)
Limiting Oxygen Index
Same in both: Min Service Temperature -180°C-292 °F · Max Service Temperature (short-term) 200°C392 °F
Electrical
Conductivity and insulation.
Electrical Resistivity
Dielectric Constant (1 MHz)
Dissipation Factor (1 MHz)
Chemical & Environmental
Corrosion and environmental resistance (0–100 scores).
Corrosion Resistance
UV / Weathering Resistance
Manufacturability
FabDigit workshop ratings (0–100 scores) — how each material behaves on the machine.
Machinability
Weldability
Formability (cold)
Polishability
Sustainability
Primary-production footprint per kilogram.
Embodied Energy (primary production)
Embodied Carbon (primary production)
Same in both: Typical Recycled Content 0%
Common Calculations
Ratios derived from the values above.
Specific Strength (UTS / density)
Specific Stiffness (E / density)
Thermal Diffusivity
Same in both: Thermal Shock Resistance Index 0
Strength versus weight
Yield strength against density for every polymer grade in the FabDigit library; the compared grades are highlighted. Up and left is stronger for its weight.
Manufacturing and finishing
| Capability | Phenolic Foam | PMI Foam |
|---|---|---|
| Default condition | — | — |
| Relative cost | $$ Standard | $$$$ High |
| Min. machined wall | — | — |
| Best machined surface | — | — |
Phenolic Foam vs PMI Foam — frequently asked
Is PMI Foam stronger than Phenolic Foam?
Yes. PMI Foam has a typical tensile strength of 2 MPa (0.319 ksi) against 0.15 MPa (0.0218 ksi) for Phenolic Foam — about 15 times as much.
Which is cheaper, Phenolic Foam or PMI Foam?
Phenolic Foam is the lower-cost material: it sits in the standard tier ($$) while PMI Foam is high ($$$$). Part price depends far more on geometry, tolerance and quantity than on raw stock — upload a CAD file for a live quote.
Which is easier to machine, Phenolic Foam or PMI Foam?
Phenolic Foam, by a small margin. Both rate excellent for machinability — 90/100 against 85/100 for PMI Foam.
Ready to make it?
Upload a CAD file and FabDigit prices the part in Phenolic Foam and PMI Foam side by side — material, machining time, tolerance and finish in one quote. Certified material data ships with the order on request.
Typical handbook values for the conditions named above, normalised for comparison. Hardness on non-Brinell scales is converted approximately for charting only. Request certified data with your order for design-critical properties.