T300 UD-EP
Matrix
GB CCF-300
UD-EP = uD epoxy laminate, Vf ≈ 60 %
Baseline unidirectional prepreg laminate — use for stiffness/strength-critical primary structure design values.
Values for the UD-EP condition
Other T300 grades and fills
T300 is listed in 9 conditions; see the grade overview at T300.
Compare all 9 grades and fillsHide
| Grade · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness |
|---|---|---|---|---|---|
3K plain/twill woven fabric + epoxy laminate, Vf ≈ 50 % | Quasi-balanced woven laminate for panels, tubes and cosmetic parts where drape and 2-axis properties matter. | — | 650 | 1.2 | — |
UD phenolic laminate | Choose for FST (fire-smoke-toxicity) interiors and ablative/carbon-carbon precursor parts. | — | 1,300 | 1.1 | — |
UD bismaleimide laminate, Vf ≈ 60 % | Pick when continuous service above ~150 °C is required (engine nacelle, missile, hot structure). | — | 1,750 | 1.3 | — |
UD-EPThis page UD epoxy laminate, Vf ≈ 60 % | Baseline unidirectional prepreg laminate — use for stiffness/strength-critical primary structure design values. | — | 1,860 | 1.4 | — |
3KDefault T300-3000 | Default aerospace/industrial small tow — plain and twill weaving, filament winding, prepreg for thin laminates. | — | 3,530 | 1.5 | — |
T300-1000 | Finest tow for very thin/lightweight fabrics and fine braids where drape and surface smoothness dominate cost. | — | 3,530 | 1.5 | — |
T300-6000 | Intermediate tow balancing fabric areal weight and cost for sporting goods and general industrial laminates. | — | 3,530 | 1.5 | — |
T300-12000 | Cheapest form per kg — heavy fabrics, pultrusion, filament winding of pressure vessels and industrial rollers. | — | 3,530 | 1.5 | — |
Chopped T300 fiber (3–12 mm) for compounds/SMC | Chopped/milled form for injection-moulding compounds, SMC/BMC, conductive and antistatic fillers. | — | 3,530 | 1.5 | — |
What is T300 UD-EP?
T300 UD-EP is T300 in the UD-EP condition — baseline unidirectional prepreg laminate — use for stiffness/strength-critical primary structure design values. T300 UD-EP has a tensile strength of 1,860 MPa (270 ksi), stronger than 77% of composite grades. Elongation at break is 1.4% and the elastic modulus is 135 GPa (19.6 Msi). T300 UD-EP has a density of 1.6 g/cm³ (0.0578 lb/in³), lighter than 53% of composite grades. 3K is the default condition FabDigit quotes; UD-EP is available on request or by drawing note.
Advantages
- Good corrosion resistance — 92/100, better than 94% of composite grades
- Polishes to a fine finish — 55/100, better than 83% of composite grades
- Good UV / weathering resistance — 95/100, better than 78% of composite grades
Limitations
- Limited service temperature — 120°C (248 °F), worse than 78% of composite grades
T300 UD-EP properties
Typical room-temperature values for T300 UD-EP; 18 are specific to this condition. Other listed values are T300 reference data and may not represent this condition. Bars are the position among composite grades.
Physical1
T300 UD-EP has a density of 1.6 g/cm³ (0.0578 lb/in³), lighter than 53% of composite grades.
Mechanical6
T300 UD-EP has a tensile strength of 1,860 MPa (270 ksi), stronger than 77% of composite grades. Elongation at break is 1.4% and the elastic modulus is 135 GPa (19.6 Msi).
Thermal6
T300 UD-EP is rated for continuous service to 120°C (248 °F). It conducts heat at 6 W/m·K (3.47 BTU/hr·ft·°F), better than 67% of composite grades. Thermal expansion is 0.2 µm/m·K (0.111 µin/in·°F).
Electrical2
T300 UD-EP has an electrical resistivity of 1.7×10⁻⁵ Ω·m.
Chemical & Environmental3
Corrosion resistance is excellent (92/100), better than 94% of composite grades. UV resistance is excellent.
Sustainability4
Producing a kilogram of T300 UD-EP takes about 400 MJ of energy and emits 26 kg of CO₂ — more than 77% of composite grades. Typical recycled content is 0%.
Manufacturability2
T300 UD-EP's machinability is poor (25/100, worse than 65% of composite grades).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with T300 UD-EP
Is T300 easy to machine?
Cured laminates must be cut/drilled with PCD or diamond-coated tooling at high speed and low feed, backed up to prevent delamination; dust is conductive and requires sealed extraction.
Can T300 be welded?
Not weldable — thermoset laminates are joined by adhesive bonding or bolted/bushed joints; isolate from aluminium with glass ply or sealant to avoid galvanic corrosion.
Can T300 be formed, bent or molded?
Processed as prepreg autoclave/oven cure (typ. 120–180 °C epoxy, 0.3–0.6 MPa), RTM/infusion, filament winding or pultrusion; drape of 3K woven fabric is good, UD tape needs careful ply-drop design.
What surface finishes work on T300?
Surface finished with peel-ply plus fill-primer, clear UV-blocking topcoat for visible weave; never anodize/plate directly, and seal edges to stop moisture wicking.
T300 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 |
|---|---|---|
| Ccarbon content of PAN-based standard-modulus fiber | 92 – 95 | 93 |
| Nresidual nitrogen from PAN precursor | 3 – 6 | 5 |
| Osurface oxygen after electrolytic surface treatment | 0.5 – 3 | 1.5 |
| epoxy sizing40B/50B/60E size level, wt % | 0.7 – 1.5 | 1 |
| Na+K (alkali)impurity limit | ≤ 0.01 | 0 |
T300 UD-EP — frequently asked
What is T300 UD-EP used for?
T300 UD-EP is typically used for aircraft secondary structures, sporting goods, pressure vessels, wind turbine spars and automotive body panels. In short: industry benchmark carbon fiber; widest prepreg availability; lowest-cost aerospace-grade tow.
What is the tensile strength of T300 UD-EP?
T300 UD-EP has a typical tensile strength of 1,860 MPa (270 ksi) — stronger than 77% of composite grades. Strength varies by condition: see the 9 listed tempers.
Is T300 UD-EP easy to machine?
Not especially — machinability is rated poor (25/100, worse than 65% of composite grades). Cured laminates must be cut/drilled with PCD or diamond-coated tooling at high speed and low feed, backed up to prevent delamination; dust is conductive and requires sealed extraction.
Can T300 UD-EP be welded?
Not weldable — thermoset laminates are joined by adhesive bonding or bolted/bushed joints; isolate from aluminium with glass ply or sealant to avoid galvanic corrosion.
What surface finishes work on T300 UD-EP?
Surface finished with peel-ply plus fill-primer, clear UV-blocking topcoat for visible weave; never anodize/plate directly, and seal edges to stop moisture wicking.
Can T300 UD-EP be formed, bent or molded?
Processed as prepreg autoclave/oven cure (typ. 120–180 °C epoxy, 0.3–0.6 MPa), RTM/infusion, filament winding or pultrusion; drape of 3K woven fabric is good, UD tape needs careful ply-drop design.
What is the maximum service temperature of T300 UD-EP?
T300 UD-EP is rated for continuous use to about 120°C (248 °F), and briefly to 500°C. Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
Sources
- TORAYCA T300 Standard Modulus Carbon Fiber Data Sheet — Toray Composite Materials (2023)
- ASM Handbook Vol. 21: Composites — ASM International (2001)
- MIL-HDBK-17 / CMH-17 Polymer Matrix Composites, carbon/epoxy lamina data — CMH-17 / SAE (2012)
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.