PA12 vs PA66
Polymer · grade comparison
PA12 and PA66 are both polymer grades, both engineering plastic. PA66 is the stronger of the two: yield strength 80 MPa (11.6 ksi) against 40 MPa (5.8 ksi) for PA12, about 100% more; tensile strength follows at 82 MPa (11.9 ksi) vs 48 MPa (6.96 ksi). PA66 is the more ductile: elongation 40% versus 18% for PA12. PA12 is lighter (1.01 g/cm³ vs 1.14 g/cm³ for PA66) and PA66 is stiffer (3 GPa vs 1.7 GPa). On the shop floor, PA66 welds better (very good vs good).
PA12Choose it when weight is the constraint.
PA66Choose it when strength drives the design, or when the part is bent, formed or impact-loaded.
PA12 vs PA66: 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
Fracture Toughness (K_IC)
Izod Impact, Notched
Hardness, Shore D
Hardness, Rockwell R
Bulk Modulus
Hardness, Rockwell M
Physical
Density and transition temperatures.
Density
Melting Temperature (Tm)
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
Specific Heat Capacity
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: Min Service Temperature -40°C-40 °F
Electrical
Conductivity and insulation.
Electrical Resistivity
Dielectric Constant (1 MHz)
Dissipation Factor (1 MHz)
Volume Resistivity
Same in both: Dielectric Strength 22 kV/mm559 V/mil · Surface Resistivity 1×10¹³ Ω · 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
Polishability
Formability (cold)
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)
Specific Stiffness (E / density)
Modulus of Resilience
Thermal Diffusivity
Same in both: 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 | PA12 | PA66 |
|---|---|---|
| 3D printing | Yes | — |
| CNC machining | — | Yes |
| Sheet metal | — | Yes |
| Injection molding | — | Yes |
| Default condition | Unfilled | Unfilled |
| Relative cost | $$ Standard | $$ Standard |
| Min. machined wall | — | 0.5 mm |
| Best machined surface | — | Ra 0.8 µm |
| Chrome Plating (Plastic) | — | Yes |
| Conductive Coating | Yes | — |
| Dyeing (Nylon) | Yes | — |
| Primer Coating | Yes | — |
| Spray Painting | — | Yes |
| Tinted Coating | Yes | — |
| Vacuum Metallization | Yes | — |
| Waterproof Coating | Yes | — |
They share 4 finishes: EMI Shielding Coating, Painting, Soft Touch Coating, UV Coating.
PA12 vs PA66 — frequently asked
Is PA66 stronger than PA12?
Yes. PA66 has a typical yield strength of 80 MPa (11.6 ksi) against 40 MPa (5.8 ksi) for PA12 — about 100% more. Tensile strength is 82 MPa (11.9 ksi) vs 48 MPa (6.96 ksi).
Which is cheaper, PA12 or PA66?
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, PA12 or PA66?
PA66, by a small margin. Both rate good for machinability — 65/100 against 60/100 for PA12; for welding the order is PA66 first (very good, 70/100) then PA12 (good, 60/100).
Ready to make it?
Upload a CAD file and FabDigit prices the part in PA12 and PA66 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.