IR vs TPE
Polymer · grade comparison
IR and TPE are both polymer grades. IR is the stronger of the two: tensile strength 22 MPa (3.19 ksi) against 8 MPa (1.09 ksi) for TPE, about 193% more. IR is the more ductile: elongation 750% versus 480% for TPE. IR is lighter (0.93 g/cm³ vs 0.96 g/cm³ for TPE) and TPE is stiffer (0.01 GPa vs 0 GPa).
IRChoose it when strength drives the design, or when the part is bent, formed or impact-loaded.
TPEChoose it when the part sees heat.
IR vs TPE: 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
Shear Modulus
Poisson's Ratio
Tensile Strength (Ultimate)
Elongation at Break
Hardness, Shore A
Tear Strength
Compression Set (22 h, 70 °C)
Compressive Strength
Flexural Modulus
Shear Strength
Hardness, Shore D
Same in both: Bulk Modulus 2 GPa0.29 Msi
Physical
Density and transition temperatures.
Density
Glass Transition (Tg)
Water Absorption (24 h)
Refractive Index
Melting Temperature (Tm)
Water Absorption (Saturation)
Thermal
How each material carries heat and how hot it can run.
Thermal Conductivity
Thermal Expansion (CTE, 20–100 °C)
Max Service Temperature (continuous)
Min Service Temperature
Limiting Oxygen Index
Max Service Temperature (short-term)
Heat Deflection Temp. @ 0.45 MPa
Vicat Softening Point (B50)
Same in both: Specific Heat Capacity 1,900 J/kg·K0.45 BTU/lb·°F
Electrical
Conductivity and insulation.
Dielectric Strength
Dissipation Factor (1 MHz)
Same in both: Electrical Resistivity 1×10¹³ Ω·m3.94×10²⁰ µΩ·in · Dielectric Constant (1 MHz) 2.6 · Volume Resistivity 1×10¹⁵ Ω·cm
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.
Formability (cold)
Mold Shrinkage
Mold Temperature (typ.)
Weldability
Polishability
Melt Flow Rate
Processing Melt Temperature (typ.)
Same in both: Machinability 25 / 100
Sustainability
Primary-production footprint per kilogram.
Embodied Carbon (primary production)
Embodied Water
Typical Recycled Content
Same in both: Embodied Energy (primary production) 95 MJ/kg40,843 BTU/lb
Common Calculations
Ratios derived from the values above.
Specific Strength (UTS / density)
Thermal Shock Resistance Index
Same in both: Specific Stiffness (E / density) 0 MN·m/kg · Thermal Diffusivity 0.1 mm²/s
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 | IR | TPE |
|---|---|---|
| Injection molding | — | Yes |
| Default condition | — | Shore A 30 to Shore A 90 |
| Relative cost | $$ Standard | $$ Standard |
| Min. machined wall | — | — |
| Best machined surface | — | — |
| Chrome Plating (Plastic) | — | Yes |
| EMI Shielding Coating | — | Yes |
| Soft Touch Coating | — | Yes |
| Spray Painting | — | Yes |
| UV Coating | — | Yes |
IR vs TPE — frequently asked
Is IR stronger than TPE?
Yes. IR has a typical tensile strength of 22 MPa (3.19 ksi) against 8 MPa (1.09 ksi) for TPE — about 193% more.
Which is cheaper, IR or TPE?
Both sit in the same relative cost tier ($$, standard); the part price will be decided by machining time, tolerance and quantity rather than by the material.
When should I choose IR over TPE?
Pick IR when strength drives the design, or when the part is bent, formed or impact-loaded. Pick TPE when the part sees heat.
Ready to make it?
Upload a CAD file and FabDigit prices the part in IR and TPE 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.