PU Cast vs UHMW-PE
Polymer · grade comparison
PU Cast and UHMW-PE are both polymer grades, both wear resistant plastic. UHMW-PE is the stronger of the two: tensile strength 40 MPa (5.8 ksi) against 12 MPa (1.74 ksi) for PU Cast, about 3.3 times as much. In exchange, PU Cast is the more ductile: elongation 700% versus 350% for UHMW-PE, and UHMW-PE is harder (64 Shore D vs 10 Shore D). UHMW-PE is lighter (0.94 g/cm³ vs 1.1 g/cm³ for PU Cast) and UHMW-PE is stiffer (0.72 GPa vs 0 GPa). On the shop floor, UHMW-PE machines more easily (very good vs poor).
PU CastChoose it when the part is bent, formed or impact-loaded.
UHMW-PEChoose it when strength drives the design, or when weight is the constraint.
PU Cast vs UHMW-PE: 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
Bulk Modulus
Poisson's Ratio
Tensile Strength (Ultimate)
Elongation at Break
Compressive Strength
Shear Strength
Hardness, Shore A
Hardness, Shore D
Tear Strength
Compression Set (22 h, 70 °C)
Yield Strength (0.2% offset)
Compressive Modulus
Flexural Strength
Flexural Modulus
Fracture Toughness (K_IC)
Izod Impact, Notched
Hardness, Rockwell R
Physical
Density and transition temperatures.
Density
Glass Transition (Tg)
Water Absorption (24 h)
Water Absorption (Saturation)
Refractive Index
Melting Temperature (Tm)
Thermal
How each material carries heat and how hot it can run.
Thermal Conductivity
Specific Heat Capacity
Min Service Temperature
Limiting Oxygen Index
Max Service Temperature (short-term)
Heat Deflection Temp. @ 0.45 MPa
Heat Deflection Temp. @ 1.8 MPa
Vicat Softening Point (B50)
Same in both: Thermal Expansion (CTE, 20–100 °C) 200 µm/m·K111 µin/in·°F · Max Service Temperature (continuous) 80°C176 °F
Electrical
Conductivity and insulation.
Electrical Resistivity
Dielectric Strength
Dielectric Constant (1 MHz)
Dissipation Factor (1 MHz)
Volume Resistivity
Surface Resistivity
Comparative Tracking Index (CTI)
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
Formability (cold)
Mold Shrinkage
Processing Melt Temperature (typ.)
Mold Temperature (typ.)
Same in both: Weldability 15 / 100 · Polishability 25 / 100
Sustainability
Primary-production footprint per kilogram.
Embodied Energy (primary production)
Embodied Carbon (primary production)
Embodied Water
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
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 | PU Cast | UHMW-PE |
|---|---|---|
| CNC machining | — | Yes |
| Sheet metal | — | Yes |
| Default condition | Shore A 40 | FDA |
| Relative cost | $$ Standard | $$ Standard |
| Min. machined wall | — | 0.5 mm |
| Best machined surface | — | Ra 0.8 µm |
| Painting | — | Yes |
Both are offered for Injection molding. They share 5 finishes: Chrome Plating (Plastic), EMI Shielding Coating, Soft Touch Coating, Spray Painting, UV Coating.
PU Cast vs UHMW-PE — frequently asked
Is UHMW-PE stronger than PU Cast?
Yes. UHMW-PE has a typical tensile strength of 40 MPa (5.8 ksi) against 12 MPa (1.74 ksi) for PU Cast — about 3.3 times as much.
Which is cheaper, PU Cast or UHMW-PE?
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.
Which is easier to machine, PU Cast or UHMW-PE?
UHMW-PE. Its machinability rates very good (75/100) against poor (25/100) for PU Cast.
Ready to make it?
Upload a CAD file and FabDigit prices the part in PU Cast and UHMW-PE 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.