PAR vs PC
Polymer · grade comparison
PAR and PC are both polymer grades. PAR is the stronger of the two: yield strength 68 MPa (9.86 ksi) against 63 MPa (9.14 ksi) for PC, about 8% more; tensile strength follows at 72 MPa (10.4 ksi) vs 68 MPa (9.86 ksi). In exchange, PC is the more ductile: elongation 110% versus 60% for PAR. PC is stiffer (2.4 GPa vs 2.1 GPa) and PAR runs hotter in service (150°C vs 120°C continuous). On the shop floor, PC welds better (very good vs good) and PC sits in a lower cost tier (budget, $) than PAR (high, $$$$).
PARChoose it when strength drives the design, or when the part sees heat.
PCChoose it when the part is bent, formed or impact-loaded, or when it will be welded.
PAR vs PC: 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
Poisson's Ratio
Tensile Strength (Ultimate)
Yield Strength (0.2% offset)
Elongation at Break
Compressive Strength
Compressive Modulus
Flexural Strength
Flexural Modulus
Shear Strength
Izod Impact, Notched
Hardness, Shore D
Hardness, Rockwell M
Hardness, Rockwell R
Fracture Toughness (K_IC)
Same in both: Bulk Modulus 4 GPa0.51 Msi
Physical
Density and transition temperatures.
Density
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
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 1,200 J/kg·K0.29 BTU/lb·°F
Electrical
Conductivity and insulation.
Dielectric Strength
Dielectric Constant (1 MHz)
Dissipation Factor (1 MHz)
Comparative Tracking Index (CTI)
Same in both: Electrical Resistivity 1×10¹⁴ Ω·m3.94×10²¹ µΩ·in · Volume Resistivity 1×10¹⁶ Ω·cm · Surface Resistivity 1×10¹⁵ Ω
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.)
Melt Flow Rate
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 | PAR | PC |
|---|---|---|
| CNC machining | — | Yes |
| Sheet metal | — | Yes |
| Injection molding | — | Yes |
| 3D printing | — | Yes |
| Default condition | — | Unfilled |
| Relative cost | $$$$ High | $ Budget |
| Min. machined wall | — | 0.5 mm |
| Best machined surface | — | Ra 0.8 µm |
| Chrome Plating (Plastic) | — | Yes |
| Conductive Coating | — | Yes |
| Dyeing (Nylon) | — | Yes |
| EMI Shielding Coating | — | Yes |
| Painting | — | Yes |
| Primer Coating | — | Yes |
| Soft Touch Coating | — | Yes |
| Spray Painting | — | Yes |
| Tinted Coating | — | Yes |
| UV Coating | — | Yes |
| Vacuum Metallization | — | Yes |
| Waterproof Coating | — | Yes |
PAR vs PC — frequently asked
Is PAR stronger than PC?
Yes. PAR has a typical yield strength of 68 MPa (9.86 ksi) against 63 MPa (9.14 ksi) for PC — about 8% more. Tensile strength is 72 MPa (10.4 ksi) vs 68 MPa (9.86 ksi).
Which is cheaper, PAR or PC?
PC is the lower-cost material: it sits in the budget tier ($) while PAR is high ($$$$). 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, PAR or PC?
PC, by a small margin. Both rate good for machinability — 65/100 against 58/100 for PAR; for welding the order is PC first (very good, 70/100) then PAR (good, 60/100).
Ready to make it?
Upload a CAD file and FabDigit prices the part in PAR and PC 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.