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3501-6 UD-IM6

Reinforced grade

UD-IM6 = iM6/3501-6 intermediate-modulus unidirectional tape

Choose when stiffness- and tension-critical (IM6/IM7 fibre) performance is needed; matrix-limited compression and toughness are unchanged.

High cost $$$$

Values for the UD-IM6 condition

Other 3501-6 grades and fills

3501-6 is listed in 6 conditions; see the grade overview at 3501-6.

Compare all 6 grades and fillsHide
Grade · open for datasheetBest forYield MPaTensile MPaElong. %Hardness
3501-6 neat cured resin casting
Unreinforced cured matrix data — used for micromechanics modelling, adhesive/film comparison and toughness benchmarking.—681.7108 HRM
AS4/3501-6 quasi-isotropic laminate [0/±45/90]s
Design-level numbers for a balanced/symmetric skin layup — use for panel sizing rather than lamina allowables.—6201.2—
AS4 8-harness satin fabric / 3501-6
Woven-fabric prepreg for drapeable contoured skins and better handling/damage tolerance at the cost of ~25% lower in-plane properties.—7801.2—
T300/3501-6 unidirectional tape
Standard-modulus Toray T300 version — the most common benchmark system in composite-mechanics literature and FE material libraries.—1,7001.3—
UD-AS4Default
AS4/3501-6 unidirectional tape
The industry-reference 350 °F-cure UD tape — pick for maximum axial stiffness/strength in laminated aerospace structure.—2,1001.5—
UD-IM6This page
IM6/3501-6 intermediate-modulus unidirectional tape
Choose when stiffness- and tension-critical (IM6/IM7 fibre) performance is needed; matrix-limited compression and toughness are unchanged.—2,7001.5—

What is 3501-6 UD-IM6?

3501-6 UD-IM6 is 3501-6 in the UD-IM6 grade — choose when stiffness- and tension-critical (IM6/IM7 fibre) performance is needed; matrix-limited compression and toughness are unchanged. 3501-6 UD-IM6 has a tensile strength of 2,700 MPa (392 ksi), stronger than 78% of composite grades. Elongation at break is 1.5% and the elastic modulus is 177 GPa (25.7 Msi). 3501-6 UD-IM6 has a density of 1.58 g/cm³ (0.0571 lb/in³), lighter than 54% of composite grades. Its glass-transition temperature is 200°C (392 °F). UD-AS4 is the default condition FabDigit quotes; UD-IM6 is available on request or by drawing note.

Advantages

  • Low moisture uptake — 0.1%, better than 85% of composite grades
  • Stiff — 177 GPa (25.7 Msi), better than 76% of composite grades

Limitations

  • Degrades in UV without stabilisers — 25/100, worse than 86% of composite grades

3501-6 UD-IM6 properties

Typical room-temperature values for 3501-6 UD-IM6; 15 are specific to this condition. Other listed values are 3501-6 reference data and may not represent this condition. Bars are the position among composite grades.

Physical4

3501-6 UD-IM6 has a density of 1.58 g/cm³ (0.0571 lb/in³), lighter than 54% of composite grades. Its glass-transition temperature is 200°C (392 °F).

Density1.58 g/cm³0.06 lb/in³
Glass Transition (Tg)200°C392 °F
Water Absorption (24 h)0.1%
Water Absorption (Saturation)1.4%

Mechanical10

3501-6 UD-IM6 has a tensile strength of 2,700 MPa (392 ksi), stronger than 78% of composite grades. Elongation at break is 1.5% and the elastic modulus is 177 GPa (25.7 Msi).

Elastic (Young's) Modulus177 GPa25.7 Msi
Shear Modulus7 GPa1 Msi
Poisson's Ratio0.3
Tensile Strength (Ultimate)2,700 MPa392 ksi
Elongation at Break1.5%
Compressive Strength1,500 MPa218 ksi
Compressive Modulus130 GPa18.9 Msi
Flexural Strength2,000 MPa290 ksi
Flexural Modulus160 GPa23.2 Msi
Shear Strength95 MPa13.8 ksi

Thermal7

3501-6 UD-IM6 is rated for continuous service to 121°C (250 °F). It conducts heat at 5 W/m·K (2.89 BTU/hr·ft·°F), better than 64% of composite grades. Thermal expansion is -0.4 µm/m·K (-0.222 µin/in·°F).

Thermal Conductivity5 W/m·K2.9 BTU/hr·ft·°F
Specific Heat Capacity950 J/kg·K0.23 BTU/lb·°F
Thermal Expansion (CTE, 20–100 °C)-0.4 µm/m·K-0.22 µin/in·°F
Max Service Temperature (continuous)121°C250 °F
Min Service Temperature-55°C-67 °F
Limiting Oxygen Index35%
Max Service Temperature (short-term)177°C351 °F

Electrical1

3501-6 UD-IM6 has an electrical resistivity of 1.4×10⁻⁵ Ω·m.

Electrical Resistivity1.4×10⁻⁵ Ω·m551 µΩ·in

Chemical & Environmental3

Corrosion resistance is excellent (88/100), better than 77% of composite grades. UV resistance is poor.

Corrosion ResistanceExcellent88/100
UV / Weathering ResistancePoor25/100
Chemical Resistance SummaryGood against fuels, hydraulic fluid (Skydrol attacks slowly), lubricants and dilute acids; degraded by hot moisture (plasticised, wet Tg drops ~50 °C), strong bases, MEK/chlorinated solvents on uncured resin, and by UV without paint.

Sustainability4

Producing a kilogram of 3501-6 UD-IM6 takes about 300 MJ of energy and emits 24 kg of CO₂ — more than 68% of composite grades. Typical recycled content is 0%.

Embodied Energy (primary production)300 MJ/kg128,977 BTU/lb
Embodied Carbon (primary production)24 kg CO₂/kg
Embodied Water450 L/kg53.9 gal/lb
Typical Recycled Content0%

Manufacturability3

3501-6 UD-IM6's machinability is poor (33/100, worse than 51% of composite grades).

MachinabilityPoor33/100
PolishabilityFair40/100
Mold Temperature (typ.)177°C351 °F

Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.

Working with 3501-6 UD-IM6

Is 3501-6 easy to machine?

Trim and drill with PCD or diamond-coated tooling at high speed/low feed, backing plate and dust extraction required — the cured laminate is highly abrasive and delaminates on breakout.

Can 3501-6 be welded?

Not weldable; join by co-cure, secondary bonding with 350 °F film adhesive (e.g. FM300), or bolted joints with oversize washers and sealant.

Can 3501-6 be formed, bent or molded?

Hand or ATL layup of frozen prepreg, debulk every few plies, autoclave cure 2 h at 177 °C under 0.59 MPa with 1.5–3 °C/min ramp; keep out-time under ~10 days at 21 °C.

What surface finishes work on 3501-6?

Peel-ply or light sand to remove the resin-rich surface, then prime and paint / apply surfacing film for UV and moisture protection; isolate from aluminium with glass ply or sealant to prevent galvanic corrosion.

3501-6 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
carbon fiber (AS4 PAN-based)cured laminate weight fraction; ≈60–63 vol%, prepreg resin content ≈34–35 wt%62 – 7066
TGMDA epoxy (tetraglycidyl-4,4'-methylen≈56 parts of the 3501-6 resin formulation≈ 1919
epoxy novolac (EPN-type)≈25 parts of resin≈ 88
DDS (4,4'-diaminodiphenyl sulfone) curin≈18–20 parts of resin≈ 6.56.5
BF3·monoethylamine catalystaccelerator, <1 part≈ 0.20.2

3501-6 UD-IM6 — frequently asked

What is 3501-6 UD-IM6 used for?

3501-6 UD-IM6 is typically used for aircraft primary/secondary structures, unmanned aerial vehicles and structural test coupons. In short: industry reference aerospace prepreg; classic 177 °C-cure epoxy; untoughened, extensively characterised.

What is the tensile strength of 3501-6 UD-IM6?

3501-6 UD-IM6 has a typical tensile strength of 2,700 MPa (392 ksi) — stronger than 78% of composite grades. Strength varies by condition: see the 6 listed tempers.

Is 3501-6 UD-IM6 easy to machine?

Not especially — machinability is rated poor (33/100, worse than 51% of composite grades). Trim and drill with PCD or diamond-coated tooling at high speed/low feed, backing plate and dust extraction required — the cured laminate is highly abrasive and delaminates on breakout.

Can 3501-6 UD-IM6 be welded?

Not weldable; join by co-cure, secondary bonding with 350 °F film adhesive (e.g. FM300), or bolted joints with oversize washers and sealant.

What surface finishes work on 3501-6 UD-IM6?

Peel-ply or light sand to remove the resin-rich surface, then prime and paint / apply surfacing film for UV and moisture protection; isolate from aluminium with glass ply or sealant to prevent galvanic corrosion.

Can 3501-6 UD-IM6 be formed, bent or molded?

Hand or ATL layup of frozen prepreg, debulk every few plies, autoclave cure 2 h at 177 °C under 0.59 MPa with 1.5–3 °C/min ramp; keep out-time under ~10 days at 21 °C.

What is the maximum service temperature of 3501-6 UD-IM6?

3501-6 UD-IM6 is rated for continuous use to about 121°C (250 °F), and briefly to 177°C. Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.

Sources

  1. 3501-6 epoxy matrix prepreg data — Hercules / Hexcel (1990)
  2. MIL-HDBK-17 (CMH-17) Vol. 2 — Polymer Matrix Composites, AS4/3501-6 data set — US DoD / CMH-17 (2002)
  3. ASM Engineered Materials Handbook Vol. 1 — Composites — ASM International (1987)
  4. ASTM D3039 / D6641 / D2344 / D790 test methods for composite laminates — ASTM (2017)
  5. Composite lamina property compilations (Tsai/Daniel-Ishai reference data) — academic literature (2006)

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.