HR Foam vs Integral Skin PU Foam
Polymer · grade comparison
HR Foam and Integral Skin PU Foam are both polymer grades. Integral Skin PU Foam is the stronger of the two: tensile strength 4 MPa (0.508 ksi) against 0.13 MPa (0.0189 ksi) for HR Foam, about 27 times as much. Integral Skin PU Foam is the more ductile: elongation 150% versus 130% for HR Foam. HR Foam is lighter (0.05 g/cm³ vs 0.35 g/cm³ for Integral Skin PU Foam) and Integral Skin PU Foam is stiffer (0.05 GPa vs 2×10⁻⁵ GPa). On the shop floor, HR Foam machines more easily (excellent vs fair), HR Foam welds better (fair vs not recommended), and HR Foam sits in a lower cost tier (standard, $$) than Integral Skin PU Foam (premium, $$$).
HR FoamChoose it when weight is the constraint, or when the part sees heat.
Integral Skin PU FoamChoose it when strength drives the design, or when the part is bent, formed or impact-loaded.
HR Foam vs Integral Skin PU 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
Tear Strength
Compression Set (22 h, 70 °C)
Flexural Strength
Flexural Modulus
Hardness, Shore A
Physical
Density and transition temperatures.
Density
Glass Transition (Tg)
Water Absorption (24 h)
Thermal
How each material carries heat and how hot it can run.
Thermal Conductivity
Specific Heat Capacity
Max Service Temperature (continuous)
Min Service Temperature
Limiting Oxygen Index
Thermal Expansion (CTE, 20–100 °C)
Same in both: 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
Same in both: UV / Weathering Resistance 25 / 100
Manufacturability
FabDigit workshop ratings (0–100 scores) — how each material behaves on the machine.
Machinability
Weldability
Formability (cold)
Polishability
Mold Shrinkage
Mold Temperature (typ.)
Sustainability
Primary-production footprint per kilogram.
Embodied Energy (primary production)
Embodied Carbon (primary production)
Embodied Water
Typical Recycled Content
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 | Integral Skin PU Foam |
|---|---|---|
| Default condition | — | — |
| Relative cost | $$ Standard | $$$ Premium |
| Min. machined wall | — | — |
| Best machined surface | — | — |
HR Foam vs Integral Skin PU Foam — frequently asked
Is Integral Skin PU Foam stronger than HR Foam?
Yes. Integral Skin PU Foam has a typical tensile strength of 4 MPa (0.508 ksi) against 0.13 MPa (0.0189 ksi) for HR Foam — about 27 times as much.
Which is cheaper, HR Foam or Integral Skin PU Foam?
HR Foam is the lower-cost material: it sits in the standard tier ($$) while Integral Skin PU Foam is premium ($$$). 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 Integral Skin PU Foam?
HR Foam. Its machinability rates excellent (85/100) against fair (50/100) for Integral Skin PU Foam; for welding the order is HR Foam first (fair, 40/100) then Integral Skin PU Foam (not recommended, 5/100).
Ready to make it?
Upload a CAD file and FabDigit prices the part in HR Foam and Integral Skin PU 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.