MDPE vs UHMW-PE
Polymer · grade comparison
MDPE and UHMW-PE are both polymer grades. UHMW-PE is the stronger of the two: yield strength 21 MPa (3.05 ksi) against 19 MPa (2.76 ksi) for MDPE, about 11% more; tensile strength follows at 40 MPa (5.8 ksi) vs 24 MPa (3.48 ksi). In exchange, MDPE is the more ductile: elongation 700% versus 350% for UHMW-PE, and UHMW-PE is harder (64 Shore D vs 58 Shore D). UHMW-PE runs hotter in service (80°C vs 65°C continuous). On the shop floor, UHMW-PE machines more easily (very good vs good), MDPE welds better (excellent vs poor), and MDPE sits in a lower cost tier (budget, $) than UHMW-PE (standard, $$).
MDPEChoose it when the part is bent, formed or impact-loaded, or when it will be welded.
UHMW-PEChoose it when strength drives the design, or when the part sees heat.
MDPE 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)
Yield Strength (0.2% offset)
Elongation at Break
Compressive Strength
Compressive Modulus
Flexural Strength
Flexural Modulus
Shear Strength
Fracture Toughness (K_IC)
Izod Impact, Notched
Hardness, Shore D
Hardness, Rockwell R
Physical
Density and transition temperatures.
Density
Melting Temperature (Tm)
Glass Transition (Tg)
Water Absorption (Saturation)
Refractive Index
Light Transmission
Same in both: Water Absorption (24 h) 0.01%
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
Heat Deflection Temp. @ 0.45 MPa
Heat Deflection Temp. @ 1.8 MPa
Vicat Softening Point (B50)
Limiting Oxygen Index
Max Service Temperature (short-term)
Electrical
Conductivity and insulation.
Electrical Resistivity
Dielectric Strength
Volume Resistivity
Surface Resistivity
Same in both: Dielectric Constant (1 MHz) 2.3 · Dissipation Factor (1 MHz) 3×10⁻⁴ · Comparative Tracking Index (CTI) 600 V
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
Mold Shrinkage
Melt Flow Rate
Processing Melt Temperature (typ.)
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)
Modulus of Resilience
Same in both: Specific Stiffness (E / density) 0.8 MN·m/kg · Thermal Diffusivity 0.2 mm²/s · Thermal Shock Resistance Index 0
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 | MDPE | UHMW-PE |
|---|---|---|
| CNC machining | — | Yes |
| Sheet metal | — | Yes |
| Injection molding | — | Yes |
| Default condition | — | FDA |
| Relative cost | $ Budget | $$ Standard |
| Min. machined wall | — | 0.5 mm |
| Best machined surface | — | Ra 0.8 µm |
| Chrome Plating (Plastic) | — | Yes |
| EMI Shielding Coating | — | Yes |
| Painting | — | Yes |
| Soft Touch Coating | — | Yes |
| Spray Painting | — | Yes |
| UV Coating | — | Yes |
MDPE vs UHMW-PE — frequently asked
Is UHMW-PE stronger than MDPE?
Yes. UHMW-PE has a typical yield strength of 21 MPa (3.05 ksi) against 19 MPa (2.76 ksi) for MDPE — about 11% more. Tensile strength is 40 MPa (5.8 ksi) vs 24 MPa (3.48 ksi).
Which is cheaper, MDPE or UHMW-PE?
MDPE is the lower-cost material: it sits in the budget tier ($) while UHMW-PE is standard ($$). 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, MDPE or UHMW-PE?
UHMW-PE. Its machinability rates very good (75/100) against good (55/100) for MDPE; for welding the order is MDPE first (excellent, 95/100) then UHMW-PE (poor, 15/100).
Ready to make it?
Upload a CAD file and FabDigit prices the part in MDPE 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.