CPVC vs PVC-U
Polymer · grade comparison
CPVC and PVC-U are both polymer grades. CPVC is the stronger of the two: tensile strength 55 MPa (7.98 ksi) against 52 MPa (7.54 ksi) for PVC-U, about 6% more. PVC-U is lighter (1.42 g/cm³ vs 1.54 g/cm³ for CPVC) and CPVC runs hotter in service (93°C vs 60°C continuous). On the shop floor, PVC-U welds better (excellent vs good).
CPVCChoose it when strength drives the design, or when the part sees heat.
PVC-UChoose it when weight is the constraint, or when it will be welded.
CPVC 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.
Poisson's Ratio
Tensile Strength (Ultimate)
Compressive Strength
Compressive Modulus
Flexural Strength
Flexural Modulus
Shear Strength
Izod Impact, Notched
Hardness, Rockwell R
Bulk Modulus
Fracture Toughness (K_IC)
Hardness, Rockwell M
Same in both: Elastic (Young's) Modulus 3 GPa0.44 Msi · Shear Modulus 1.1 GPa0.16 Msi · Yield Strength (0.2% offset) 52 MPa7.5 ksi · Elongation at Break 25% · Hardness, Shore D 82 Shore D
Physical
Density and transition temperatures.
Density
Glass Transition (Tg)
Water Absorption (24 h)
Water Absorption (Saturation)
Refractive Index
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
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: Specific Heat Capacity 950 J/kg·K0.23 BTU/lb·°F
Electrical
Conductivity and insulation.
Dielectric Strength
Dielectric Constant (1 MHz)
Dissipation Factor (1 MHz)
Surface Resistivity
Same in both: Electrical Resistivity 1×10¹³ Ω·m3.94×10²⁰ µΩ·in · Volume Resistivity 1×10¹⁵ Ω·cm · Comparative Tracking Index (CTI) 600 V
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
Mold Shrinkage
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)
Specific Stiffness (E / density)
Same in both: Modulus of Resilience 451 kJ/m³ · 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 | CPVC | PVC-U |
|---|---|---|
| CNC machining | Yes | — |
| Sheet metal | Yes | — |
| Injection molding | Yes | — |
| Default condition | Unfilled | — |
| Relative cost | $$ Standard | $$ 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 | — |
CPVC vs PVC-U — frequently asked
Is CPVC stronger than PVC-U?
Yes. CPVC has a typical tensile strength of 55 MPa (7.98 ksi) against 52 MPa (7.54 ksi) for PVC-U — about 6% more.
Which is cheaper, CPVC 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, CPVC or PVC-U?
PVC-U, by a small margin. Both rate very good for machinability — 80/100 against 75/100 for CPVC; for welding the order is PVC-U first (excellent, 90/100) then CPVC (good, 65/100).
Ready to make it?
Upload a CAD file and FabDigit prices the part in CPVC 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.