FabDigit

PA66 · grade

PA66-IM

Properties of the IM condition, compared with the other PA66 grades.

Rubber-toughened PA66 for parts needing high notched and cold impact (housings, snap-fits, sporting goods).

What is PA66-IM?

PA66-IM is PA66 in the IM grade — rubber-toughened PA66 for parts needing high notched and cold impact (housings, snap-fits, sporting goods). PA66-IM has a yield strength of 50 MPa (7.25 ksi) and a tensile strength of 52 MPa (7.54 ksi) — weaker than 52% of polymer grades. Elongation at break is 60% and the elastic modulus is 1.9 GPa (0.276 Msi). PA66-IM has a density of 1.08 g/cm³ (0.039 lb/in³), lighter than 66% of polymer grades. Its glass-transition temperature is 70°C (158 °F). Unfilled is the default condition FabDigit quotes; IM is available on request or by drawing note.

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-IM properties

Typical room-temperature values for PA66-IM — 10 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-IM has a density of 1.08 g/cm³ (0.039 lb/in³), lighter than 66% of polymer grades. Its glass-transition temperature is 70°C (158 °F).

Density1.08 g/cm³0.04 lb/in³
Melting Temperature (Tm)262°C504 °F
Glass Transition (Tg)70°C158 °F
Water Absorption (24 h)1.3%
Water Absorption (Saturation)8.5%
Refractive Index1.53

Mechanical17

PA66-IM has a yield strength of 50 MPa (7.25 ksi) and a tensile strength of 52 MPa (7.54 ksi) — weaker than 52% of polymer grades. Elongation at break is 60% and the elastic modulus is 1.9 GPa (0.276 Msi).

Elastic (Young's) Modulus1.9 GPa0.28 Msi
Shear Modulus1.1 GPa0.16 Msi
Bulk Modulus5 GPa0.65 Msi
Poisson's Ratio0.39
Tensile Strength (Ultimate)52 MPa7.5 ksi
Yield Strength (0.2% offset)50 MPa7.3 ksi
Elongation at Break60%
Compressive Strength95 MPa13.8 ksi
Compressive Modulus2.8 GPa0.41 Msi
Flexural Strength105 MPa15.2 ksi
Flexural Modulus1.8 GPa0.26 Msi
Shear Strength60 MPa8.7 ksi
Fracture Toughness (K_IC)3 MPa·√m2.7 ksi·√in
Izod Impact, Notched900 J/m16.9 ft·lbf/in
Hardness, Shore D81 Shore D
Hardness, Rockwell M85 HRM
Hardness, Rockwell R110 HRR

Thermal11

PA66-IM 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).

Thermal Conductivity0.25 W/m·K0.14 BTU/hr·ft·°F
Specific Heat Capacity1,670 J/kg·K0.4 BTU/lb·°F
Thermal Expansion (CTE, 20–100 °C)85 µm/m·K47.2 µin/in·°F
Max Service Temperature (continuous)100°C212 °F
Min Service Temperature-50°C-58 °F
Heat Deflection Temp. @ 0.45 MPa220°C428 °F
Heat Deflection Temp. @ 1.8 MPa60°C140 °F
Vicat Softening Point (B50)200°C392 °F
Flammability (UL 94)HB at 1.6 mm
Limiting Oxygen Index25%
Max Service Temperature (short-term)170°C338 °F

Electrical7

PA66-IM is an electrical insulator with a dielectric strength of 22 kV/mm (558.8 V/mil) and a resistivity of 1×10¹² Ω·m.

Electrical Resistivity1×10¹² Ω·m3.94×10¹⁹ µΩ·in
Dielectric Strength22 kV/mm559 V/mil
Dielectric Constant (1 MHz)3.4
Dissipation Factor (1 MHz)0.02
Volume Resistivity1×10¹⁴ Ω·cm
Surface Resistivity1×10¹³ Ω
Comparative Tracking Index (CTI)600 V

Chemical & Environmental3

Corrosion resistance is good (60/100), worse than 91% of polymer grades. UV resistance is poor.

Corrosion ResistanceGood60/100
UV / Weathering ResistancePoor30/100
Chemical Resistance SummaryGood against hydrocarbons, oils, greases, fuels, alcohols and most alkalis; attacked by strong mineral acids, formic acid, phenols and cresols; hydrolyses in prolonged hot water/steam and degrades in zinc/calcium chloride solutions.

Sustainability4

Producing a kilogram of PA66-IM takes about 120 MJ of energy and emits 6.7 kg of CO₂ — more than 73% of polymer grades. Typical recycled content is 5%.

Embodied Energy (primary production)120 MJ/kg51,591 BTU/lb
Embodied Carbon (primary production)6.7 kg CO₂/kg
Embodied Water300 L/kg35.9 gal/lb
Typical Recycled Content5%

Manufacturability8

PA66-IM's machinability is good (65/100, better than 66% of polymer grades); weldability very good (70/100); formability fair (50/100).

MachinabilityGood65/100
WeldabilityVery good70/100
Formability (cold)Fair50/100
PolishabilityGood60/100
Mold Shrinkage1.5%
Melt Flow Rate30 g/10 min
Processing Melt Temperature (typ.)290°C554 °F
Mold Temperature (typ.)80°C176 °F

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.

Working with PA66-IM

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.

ElementSpec limit (wt %)Nominal
heat/light stabilizers, lubricants, nuclAdditive package varies by grade (Cu/halide, HALS, carbon black, mold release)0 – 30.5
glass fiberOnly in GF15/GF30/GF50 variants (silane-sized E-glass)0 – 500
carbon fiberOnly in CF20/CF30 variants0 – 300
flame retardant systemOnly in FR V-0 variant (brominated + Sb2O3 or halogen-free phosphinate)0 – 250
poly(hexamethylene adipamide) — hexamethBase resin; nominal 1:1 diamine/diacid molar ratio≥ 97 (balance)

PA66-IM — frequently asked

What is PA66-IM used for?

PA66-IM 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-IM?

PA66-IM has a typical yield strength of 50 MPa (7.25 ksi) and a tensile strength of 52 MPa (7.54 ksi) — weaker than 52% of polymer grades. Strength varies by condition: see the 15 listed tempers.

Is PA66-IM 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-IM 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-IM?

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-IM 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-IM?

PA66-IM 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 50 MPa in Unfilled versus 50 MPa in IM.

Can FabDigit make parts in PA66-IM?

Yes — PA66-IM 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

  1. ISO 16396-1/-2 Plastics — Polyamide (PA) moulding and extrusion materialsISO (2022)
  2. ASTM D4066 Standard Classification System for Nylon Injection and Extrusion MaterialsASTM (2019)
  3. Zytel PA66 product datasheets (101, 70G33, ST801)DuPont / Celanese (2023)
  4. Ultramid A (PA66) product range brochureBASF (2022)
  5. Ertalon 66 SA stock shape datasheetMitsubishi Chemical Advanced Materials (2021)
  6. Tecamid 66 / Tecamid 66 GF30 datasheetsEnsinger (2022)
  7. CAMPUS plastics database — PA66 gradesCWFG / CAMPUS consortium (2024)
  8. Engineering Plastics — Engineered Materials Handbook Vol. 2ASM 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.