PVC-O vs PVC-U
Polymer · grade comparison
PVC-O and PVC-U are both polymer grades. PVC-O is the stronger of the two: yield strength 58 MPa (8.41 ksi) against 52 MPa (7.54 ksi) for PVC-U, about 12% more; tensile strength follows at 78 MPa (11.3 ksi) vs 52 MPa (7.54 ksi). PVC-O is the more ductile: elongation 90% versus 25% for PVC-U. PVC-O is stiffer (3.8 GPa vs 3 GPa) and PVC-U runs hotter in service (60°C vs 45°C continuous). On the shop floor, PVC-U machines more easily (80 vs 70 out of 100) and PVC-U welds better (excellent vs poor).
PVC-OChoose it when strength drives the design, or when the part is bent, formed or impact-loaded.
PVC-UChoose it when the part sees heat, or when the part is machined in volume.
PVC-O vs PVC-U: 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)
Yield Strength (0.2% offset)
Elongation at Break
Compressive Strength
Flexural Strength
Flexural Modulus
Shear Strength
Fracture Toughness (K_IC)
Izod Impact, Notched
Shear Modulus
Bulk Modulus
Compressive Modulus
Hardness, Rockwell M
Same in both: Hardness, Shore D 82 Shore D · Hardness, Rockwell R 115 HRR
Physical
Density and transition temperatures.
Density
Water Absorption (24 h)
Refractive Index
Same in both: Glass Transition (Tg) 80°C176 °F · Water Absorption (Saturation) 0.2%
Thermal
How each material carries heat and how hot it can run.
Thermal Expansion (CTE, 20–100 °C)
Max Service Temperature (continuous)
Heat Deflection Temp. @ 0.45 MPa
Heat Deflection Temp. @ 1.8 MPa
Vicat Softening Point (B50)
Limiting Oxygen Index
Max Service Temperature (short-term)
Same in both: Thermal Conductivity 0.16 W/m·K0.09 BTU/hr·ft·°F · Specific Heat Capacity 950 J/kg·K0.23 BTU/lb·°F · Min Service Temperature -10°C14 °F
Electrical
Conductivity and insulation.
Dielectric Strength
Dielectric Constant (1 MHz)
Dissipation Factor (1 MHz)
Surface Resistivity
Comparative Tracking Index (CTI)
Same in both: Electrical Resistivity 1×10¹³ Ω·m3.94×10²⁰ µΩ·in · 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.
Machinability
Weldability
Formability (cold)
Polishability
Processing Melt Temperature (typ.)
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)
Modulus of Resilience
Same in both: Thermal Diffusivity 0.1 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 | PVC-O | PVC-U |
|---|---|---|
| Default condition | — | — |
| Relative cost | $$ Standard | $$ Standard |
| Min. machined wall | — | — |
| Best machined surface | — | — |
PVC-O vs PVC-U — frequently asked
Is PVC-O stronger than PVC-U?
Yes. PVC-O has a typical yield strength of 58 MPa (8.41 ksi) against 52 MPa (7.54 ksi) for PVC-U — about 12% more. Tensile strength is 78 MPa (11.3 ksi) vs 52 MPa (7.54 ksi).
Which is cheaper, PVC-O or PVC-U?
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, PVC-O or PVC-U?
PVC-U, by a small margin. Both rate very good for machinability — 80/100 against 70/100 for PVC-O; for welding the order is PVC-U first (excellent, 90/100) then PVC-O (poor, 25/100).
Ready to make it?
Upload a CAD file and FabDigit prices the part in PVC-O and PVC-U 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.