HR Foam vs PUR/PIR Board
Polymer · grade comparison
HR Foam and PUR/PIR Board are both polymer grades. PUR/PIR Board is the stronger of the two: tensile strength 0.28 MPa (0.0406 ksi) against 0.13 MPa (0.0189 ksi) for HR Foam, about 115% more. In exchange, HR Foam is the more ductile: elongation 130% versus 8% for PUR/PIR Board. PUR/PIR Board is lighter (0.03 g/cm³ vs 0.05 g/cm³ for HR Foam) and PUR/PIR Board is stiffer (0.01 GPa vs 2×10⁻⁵ GPa). On the shop floor, PUR/PIR Board machines more easily (95 vs 85 out of 100), HR Foam welds better (fair vs not recommended), and HR Foam sits in a lower cost tier (standard, $$) than PUR/PIR Board (premium, $$$).
HR FoamChoose it when the part is bent, formed or impact-loaded, or when it will be welded.
PUR/PIR BoardChoose it when strength drives the design, or when weight is the constraint.
HR Foam vs PUR/PIR Board: 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
Tear Strength
Compression Set (22 h, 70 °C)
Shear Modulus
Flexural Strength
Flexural Modulus
Shear Strength
Physical
Density and transition temperatures.
Density
Glass Transition (Tg)
Water Absorption (24 h)
Water Absorption (Saturation)
Thermal
How each material carries heat and how hot it can run.
Thermal Conductivity
Specific Heat Capacity
Min Service Temperature
Limiting Oxygen Index
Thermal Expansion (CTE, 20–100 °C)
Same in both: Max Service Temperature (continuous) 100°C212 °F · Max Service Temperature (short-term) 120°C248 °F
Electrical
Conductivity and insulation.
Electrical Resistivity
Volume Resistivity
Dielectric Constant (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)
Sustainability
Primary-production footprint per kilogram.
Embodied Energy (primary production)
Embodied Water
Typical Recycled Content
Same in both: Embodied Carbon (primary production) 5 kg CO₂/kg
Common Calculations
Ratios derived from the values above.
Specific Strength (UTS / density)
Specific Stiffness (E / density)
Thermal Diffusivity
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 | HR Foam | PUR/PIR Board |
|---|---|---|
| Default condition | — | — |
| Relative cost | $$ Standard | $$$ Premium |
| Min. machined wall | — | — |
| Best machined surface | — | — |
HR Foam vs PUR/PIR Board — frequently asked
Is PUR/PIR Board stronger than HR Foam?
Yes. PUR/PIR Board has a typical tensile strength of 0.28 MPa (0.0406 ksi) against 0.13 MPa (0.0189 ksi) for HR Foam — about 115% more.
Which is cheaper, HR Foam or PUR/PIR Board?
HR Foam is the lower-cost material: it sits in the standard tier ($$) while PUR/PIR Board is premium ($$$). 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, HR Foam or PUR/PIR Board?
PUR/PIR Board, by a small margin. Both rate excellent for machinability — 95/100 against 85/100 for HR Foam; for welding the order is HR Foam first (fair, 40/100) then PUR/PIR Board (not recommended, 5/100).
Ready to make it?
Upload a CAD file and FabDigit prices the part in HR Foam and PUR/PIR Board 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.