PA66 · grade · default condition
PA66 Unfilled
Properties of the Unfilled condition, compared with the other PA66 grades.
Pick for tough, wear-resistant, low-cost general parts where stiffness and dimensional stability under humidity are not critical.
What is PA66 Unfilled?
PA66 Unfilled is PA66 in the Unfilled grade — pick for tough, wear-resistant, low-cost general parts where stiffness and dimensional stability under humidity are not critical. PA66 Unfilled has a yield strength of 80 MPa (11.6 ksi) and a tensile strength of 82 MPa (11.9 ksi) — stronger than 87% of polymer grades. Elongation at break is 40% and the elastic modulus is 3 GPa (0.435 Msi). PA66 Unfilled has a density of 1.14 g/cm³ (0.0412 lb/in³), lighter than 60% of polymer grades. Its glass-transition temperature is 70°C (158 °F).
Advantages
- High strength — 80 MPa (11.6 ksi), better than 87% of polymer grades
Limitations
- Needs corrosion protection — 60/100, worse than 91% of polymer grades
- Absorbs moisture — dry before molding — 1.3%, worse than 89% of polymer grades
- High embodied carbon — 6.7 kg CO₂/kg, worse than 75% of polymer grades
PA66 Unfilled properties
Typical room-temperature values for PA66 Unfilled — 9 properties are specific to this condition; the rest are grade-level values shared by every PA66 grade. Each bar shows where the value sits among the polymer grades in FabDigit's library — further right is higher.
Physical6
PA66 Unfilled has a density of 1.14 g/cm³ (0.0412 lb/in³), lighter than 60% of polymer grades. Its glass-transition temperature is 70°C (158 °F).
Mechanical17
PA66 Unfilled has a yield strength of 80 MPa (11.6 ksi) and a tensile strength of 82 MPa (11.9 ksi) — stronger than 87% of polymer grades. Elongation at break is 40% and the elastic modulus is 3 GPa (0.435 Msi).
Thermal11
PA66 Unfilled is rated for continuous service to 100°C (212 °F). It conducts heat at 0.25 W/m·K (0.144 BTU/hr·ft·°F), better than 71% of polymer grades. Thermal expansion is 85 µm/m·K (47.2 µin/in·°F).
Electrical7
PA66 Unfilled is an electrical insulator with a dielectric strength of 22 kV/mm (558.8 V/mil) and a resistivity of 1×10¹² Ω·m.
Chemical & Environmental3
Corrosion resistance is good (60/100), worse than 91% of polymer grades. UV resistance is poor.
Sustainability4
Producing a kilogram of PA66 Unfilled takes about 120 MJ of energy and emits 6.7 kg of CO₂ — more than 73% of polymer grades. Typical recycled content is 5%.
Manufacturability8
PA66 Unfilled's machinability is good (65/100, better than 66% of polymer grades); weldability very good (70/100); formability fair (50/100).
Common Calculations5
Values are nominal handbook figures for design screening. Certified mill or lot data ships with every FabDigit order on request.
Other PA66 grades and fills
PA66 is also supplied in 14 other conditions. The full side-by-side table is on the PA66 overview.
- UnfilledDefaultPick for tough, wear-resistant, low-cost general parts where stiffness and dimensional stability under humidity are not critical.82 MPa tensile
- CF30Stiffest and most dimensionally stable PA66 compound, mildly conductive; chosen for lightweight precision and ESD-sensitive parts.240 MPa tensile
- GF50Maximum stiffness and strength for metal-replacement brackets and structural housings; very abrasive and anisotropic.230 MPa tensile
- CF20High specific stiffness with lower density than glass and antistatic behaviour; use where weight and precision matter.205 MPa tensile
- GF30The workhorse structural PA66: high stiffness, ~250 °C HDT and good creep resistance for under-hood and connector parts.180 MPa tensile
- GF15Moderate stiffness/HDT boost with better surface finish and less warpage than GF30.130 MPa tensile
- MF40Mineral (talc/wollastonite) filler for isotropic shrinkage, flat parts and good paintable surface at modest stiffness gain.90 MPa tensile
- EXTMachining stock (rod, plate, tube) from extrusion; slightly higher crystallinity and stiffness than injection parts but can hold internal stress in thick sections.85 MPa tensile
- FR V-0Choose for electrical connectors, switches and housings needing a V-0 Yellow Card; expect reduced toughness and higher density.75 MPa tensile
- PTFE15–20 % PTFE (sometimes with silicone oil) for dry-running bushings, slides and gears with low friction and wear.62 MPa tensile
- IMRubber-toughened PA66 for parts needing high notched and cold impact (housings, snap-fits, sporting goods).50 MPa yield · 110 HRR
Working with PA66 Unfilled
Is PA66 easy to machine?
Machines easily with sharp, positive-rake tools, high speed and low feed; use air or flood coolant to avoid heat build-up and expect stress relief/moisture growth on tight tolerances — glass/carbon filled grades need carbide or PCD.
Can PA66 be welded?
Ultrasonic, hot-plate, spin, vibration and laser welding all work well on dry material; moisture causes porous joints, and glass content above ~30 % lowers weld factor.
Can PA66 be formed, bent or molded?
Dry to <0.15 % moisture, melt 275–300 °C, mold 60–100 °C, fast injection with generous venting; account for 1.0–2.2 % shrink (0.2–0.6 % when glass filled) and anisotropic warpage in fiber-filled parts.
What surface finishes work on PA66?
Takes acid dyeing, adhesive bonding (after plasma/primer), painting and vacuum metallizing; direct electroless plating is possible on etched grades, and moisture conditioning is often used to reach in-service dimensions.
PA66 chemical composition (wt %)
Limits by weight percent from the governing specification, written the way the spec states them — a single maximum for impurities, a range for alloying elements, and the base element as balance. Nominal is the typical mid-range value.
| Element | Spec limit (wt %) | Nominal |
|---|---|---|
| heat/light stabilizers, lubricants, nuclAdditive package varies by grade (Cu/halide, HALS, carbon black, mold release) | 0 – 3 | 0.5 |
| glass fiberOnly in GF15/GF30/GF50 variants (silane-sized E-glass) | 0 – 50 | 0 |
| carbon fiberOnly in CF20/CF30 variants | 0 – 30 | 0 |
| flame retardant systemOnly in FR V-0 variant (brominated + Sb2O3 or halogen-free phosphinate) | 0 – 25 | 0 |
| poly(hexamethylene adipamide) — hexamethBase resin; nominal 1:1 diamine/diacid molar ratio | ≥ 97 (balance) | — |
PA66 Unfilled — frequently asked
What is PA66 Unfilled used for?
PA66 Unfilled is typically used for automotive intake manifolds, cooling system housings and fans, electrical connectors, cable ties, gears and bearing bushings and fasteners and clips. In short: harder wear-resistant nylon.
What is the yield strength of PA66 Unfilled?
PA66 Unfilled has a typical yield strength of 80 MPa (11.6 ksi) and a tensile strength of 82 MPa (11.9 ksi) — stronger than 87% of polymer grades. Strength varies by condition: see the 15 listed tempers.
Is PA66 Unfilled easy to machine?
Reasonably — machinability is rated good (65/100, better than 66% of polymer grades). Machines easily with sharp, positive-rake tools, high speed and low feed; use air or flood coolant to avoid heat build-up and expect stress relief/moisture growth on tight tolerances — glass/carbon filled grades need carbide or PCD.
Can PA66 Unfilled be welded?
Yes — weldability is rated very good (70/100). Ultrasonic, hot-plate, spin, vibration and laser welding all work well on dry material; moisture causes porous joints, and glass content above ~30 % lowers weld factor.
What surface finishes work on PA66 Unfilled?
Takes acid dyeing, adhesive bonding (after plasma/primer), painting and vacuum metallizing; direct electroless plating is possible on etched grades, and moisture conditioning is often used to reach in-service dimensions.
Can PA66 Unfilled be formed, bent or molded?
Dry to <0.15 % moisture, melt 275–300 °C, mold 60–100 °C, fast injection with generous venting; account for 1.0–2.2 % shrink (0.2–0.6 % when glass filled) and anisotropic warpage in fiber-filled parts.
What is the maximum service temperature of PA66 Unfilled?
PA66 Unfilled is rated for continuous use to about 100°C (212 °F), and briefly to 170°C. Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between PA66 Unfilled and PA66-IM?
Unfilled is the default condition — pick for tough, wear-resistant, low-cost general parts where stiffness and dimensional stability under humidity are not critical. IM: rubber-toughened PA66 for parts needing high notched and cold impact (housings, snap-fits, sporting goods). Yield strength is 80 MPa in Unfilled versus 50 MPa in IM.
Can FabDigit make parts in PA66 Unfilled?
Yes — PA66 Unfilled is available for CNC machining, sheet metal and injection molding with instant online pricing. Upload a STEP file to get a price and a DFM check.
Sources
- ISO 16396-1/-2 Plastics — Polyamide (PA) moulding and extrusion materials — ISO (2022)
- ASTM D4066 Standard Classification System for Nylon Injection and Extrusion Materials — ASTM (2019)
- Zytel PA66 product datasheets (101, 70G33, ST801) — DuPont / Celanese (2023)
- Ultramid A (PA66) product range brochure — BASF (2022)
- Ertalon 66 SA stock shape datasheet — Mitsubishi Chemical Advanced Materials (2021)
- Tecamid 66 / Tecamid 66 GF30 datasheets — Ensinger (2022)
- CAMPUS plastics database — PA66 grades — CWFG / CAMPUS consortium (2024)
- Engineering Plastics — Engineered Materials Handbook Vol. 2 — ASM International (1988)
Property data is compiled from published supplier and standards handbooks and normalised for comparison. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.