EVA Foam vs Silicone
Polymer · grade comparison
EVA Foam and Silicone are both polymer grades. Silicone is the stronger of the two: tensile strength 8 MPa (1.16 ksi) against 1 MPa (0.145 ksi) for EVA Foam, about 8.0 times as much. Silicone is the more ductile: elongation 500% versus 200% for EVA Foam. EVA Foam is lighter (0.06 g/cm³ vs 1.15 g/cm³ for Silicone) and EVA Foam is stiffer (0.01 GPa vs 0 GPa). On the shop floor, EVA Foam machines more easily (excellent vs poor), EVA Foam welds better (very good vs poor), and EVA Foam sits in a lower cost tier (standard, $$) than Silicone (premium, $$$).
EVA FoamChoose it when weight is the constraint, or when the part is machined in volume.
SiliconeChoose it when strength drives the design, or when the part is bent, formed or impact-loaded.
EVA Foam vs Silicone: 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
Shear Strength
Hardness, Shore A
Tear Strength
Compression Set (22 h, 70 °C)
Shear Modulus
Bulk Modulus
Physical
Density and transition temperatures.
Density
Melting Temperature (Tm)
Glass Transition (Tg)
Water Absorption (24 h)
Water Absorption (Saturation)
Refractive Index
Light Transmission
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)
Min Service Temperature
Vicat Softening Point (B50)
Limiting Oxygen Index
Max Service Temperature (short-term)
Electrical
Conductivity and insulation.
Electrical Resistivity
Dielectric Constant (1 MHz)
Volume Resistivity
Surface Resistivity
Dielectric Strength
Dissipation Factor (1 MHz)
Comparative Tracking Index (CTI)
Chemical & Environmental
Corrosion and environmental resistance (0–100 scores).
UV / Weathering Resistance
Same in both: Corrosion Resistance 90 / 100
Manufacturability
FabDigit workshop ratings (0–100 scores) — how each material behaves on the machine.
Machinability
Weldability
Formability (cold)
Polishability
Melt Flow Rate
Processing Melt Temperature (typ.)
Mold Temperature (typ.)
Same in both: Mold Shrinkage 2.5%
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
Thermal Shock Resistance Index
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 | EVA Foam | Silicone |
|---|---|---|
| Default condition | Closed Cell | Medical Grade |
| Relative cost | $$ Standard | $$$ Premium |
| Min. machined wall | — | — |
| Best machined surface | — | — |
Both are offered for Injection molding. Both take the same 5 finishes: Chrome Plating (Plastic), EMI Shielding Coating, Soft Touch Coating, Spray Painting, UV Coating.
EVA Foam vs Silicone — frequently asked
Is Silicone stronger than EVA Foam?
Yes. Silicone has a typical tensile strength of 8 MPa (1.16 ksi) against 1 MPa (0.145 ksi) for EVA Foam — about 8.0 times as much.
Which is cheaper, EVA Foam or Silicone?
EVA Foam is the lower-cost material: it sits in the standard tier ($$) while Silicone is premium ($$$). 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, EVA Foam or Silicone?
EVA Foam. Its machinability rates excellent (85/100) against poor (20/100) for Silicone; for welding the order is EVA Foam first (very good, 70/100) then Silicone (poor, 20/100).
Ready to make it?
Upload a CAD file and FabDigit prices the part in EVA Foam and Silicone 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.