FR-2 CCL-1S-18
Grade
ASTM D709 Grade FR-2, D709 Type FR-2
CCL-1S-18 = single-sided copper-clad, 18 µm (1/2 oz) foil
Fine-line, low-current consumer boards where etch definition matters more than current capacity.
Values for the CCL-1S-18 condition
Other FR-2 grades and fills
FR-2 is listed in 6 conditions; see the grade overview at FR-2.
Compare all 6 grades and fillsHide
| Grade · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness |
|---|---|---|---|---|---|
Cold-punch grade | Standard FR-2 formulation optimized for room-temperature blanking of small boards at high volume (equivalent of XXXPC + FR). | — | 78 | 1.3 | 100 HRM |
CCL-1S-18This page Single-sided copper-clad, 18 µm (1/2 oz) foil | Fine-line, low-current consumer boards where etch definition matters more than current capacity. | — | 88 | 1.1 | 105 HRM |
CCL-1S-35Default Single-sided copper-clad, 35 µm (1 oz) foil | The default FR-2 CCL for mass-market single-sided PCBs: room-temperature punchable, cheapest board stock. | — | 92 | 1.1 | 105 HRM |
Warm-punch / higher-strength grade | Slightly higher resin content and strength for thicker boards (≥2 mm) or crack-sensitive blanking; needs pre-heating before punching. | — | 95 | 0.9 | 110 HRM |
Double-sided copper-clad, 35 µm both faces | Used only where jumper/rivet interconnect is acceptable — FR-2 paper core cannot reliably support plated through-holes. | — | 98 | 1.2 | 105 HRM |
Single-sided copper-clad, 70 µm (2 oz) foil | Higher current-carrying tracks for power supplies, ballasts and adapters; slightly harder to punch cleanly. | — | 100 | 1.2 | 105 HRM |
What is FR-2 CCL-1S-18?
FR-2 CCL-1S-18 is FR-2 in the CCL-1S-18 grade — fine-line, low-current consumer boards where etch definition matters more than current capacity. FR-2 CCL-1S-18 has a tensile strength of 88 MPa (12.8 ksi), weaker than 73% of composite grades. Elongation at break is 1.1% and the elastic modulus is 7.2 GPa (1.04 Msi). FR-2 CCL-1S-18 has a density of 1.5 g/cm³ (0.0542 lb/in³), lighter than 58% of composite grades. Its glass-transition temperature is 110°C (230 °F). CCL-1S-35 is the default condition FabDigit quotes; CCL-1S-18 is available on request or by drawing note.
Advantages
- Easy to machine — 78/100, better than 80% of composite grades
- Low embodied carbon — 4.5 kg CO₂/kg, better than 79% of composite grades
Limitations
- Low fracture toughness — 1.6 MPa·√m (1.46 ksi·√in), worse than 95% of composite grades
- Needs corrosion protection — 50/100, worse than 92% of composite grades
- Limited service temperature — 105°C (221 °F), worse than 90% of composite grades
- Degrades in UV without stabilisers — 25/100, worse than 86% of composite grades
- Limited ductility — 1.1%, worse than 78% of composite grades
FR-2 CCL-1S-18 properties
Typical room-temperature values for FR-2 CCL-1S-18; 18 are specific to this condition. Other listed values are FR-2 reference data and may not represent this condition. Bars are the position among composite grades.
Physical4
FR-2 CCL-1S-18 has a density of 1.5 g/cm³ (0.0542 lb/in³), lighter than 58% of composite grades. Its glass-transition temperature is 110°C (230 °F).
Mechanical11
FR-2 CCL-1S-18 has a tensile strength of 88 MPa (12.8 ksi), weaker than 73% of composite grades. Elongation at break is 1.1% and the elastic modulus is 7.2 GPa (1.04 Msi).
Thermal9
FR-2 CCL-1S-18 is rated for continuous service to 105°C (221 °F). It conducts heat at 0.3 W/m·K (0.173 BTU/hr·ft·°F), worse than 63% of composite grades. Thermal expansion is 20 µm/m·K (11.1 µin/in·°F).
Electrical7
FR-2 CCL-1S-18 is an electrical insulator with a dielectric strength of 20 kV/mm (508 V/mil) and a resistivity of 1×10⁹ Ω·m.
Chemical & Environmental3
Corrosion resistance is fair (50/100), worse than 92% of composite grades. UV resistance is poor.
Sustainability4
Producing a kilogram of FR-2 CCL-1S-18 takes about 85 MJ of energy and emits 4.5 kg of CO₂ — less than 79% of composite grades. Typical recycled content is 5%.
Manufacturability2
FR-2 CCL-1S-18's machinability is very good (78/100, better than 80% of composite grades).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with FR-2 CCL-1S-18
Is FR-2 easy to machine?
Blank, pierce and slot at room temperature with sharp shear-die tooling — this is FR-2's whole reason to exist; drill/rout with carbide, extract the abrasive paper dust and never plate the holes.
Can FR-2 be welded?
Not weldable — thermoset laminate; join mechanically with rivets, eyelets or screws, or bond with epoxy/cyanoacrylate.
Can FR-2 be formed, bent or molded?
Supplied fully cured and flat; cannot be post-formed or bent — design as flat blanks only, and bake before soldering if stored in humid conditions.
What surface finishes work on FR-2?
Copper is protected by HASL, OSP or roller-tinning; edges seal well with lacquer or conformal coat to limit moisture wicking into the paper core.
FR-2 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 |
|---|---|---|
| kraft cellulose paper (reinforcement)multiple plies of bleached/unbleached kraft | 42 – 58 | 50 |
| brominated flame retardanttetrabromobisphenol-A type or brominated phenolic | 3 – 10 | 6 |
| fillers / curing agents / pigments | 0 – 4 | 2 |
| electrodeposited copper foil (clad grade18/35/70 µm, additional to the laminate mass | ≈ 0 | 0 |
| phenol-formaldehyde (resole/novolac) resmatrix, may be epoxy-modified | ≥ 33 (balance) | — |
FR-2 CCL-1S-18 — frequently asked
What is FR-2 CCL-1S-18 used for?
FR-2 CCL-1S-18 is typically used for single-sided PCBs, low-cost consumer electronics substrates and general electrical insulation boards. In short: cheapest punchable PCB substrate; cold-punchable phenolic paper; single-sided boards only.
What is the tensile strength of FR-2 CCL-1S-18?
FR-2 CCL-1S-18 has a typical tensile strength of 88 MPa (12.8 ksi) — weaker than 73% of composite grades. Strength varies by condition: see the 6 listed tempers.
Is FR-2 CCL-1S-18 easy to machine?
Yes — machinability is rated very good (78/100, better than 80% of composite grades). Blank, pierce and slot at room temperature with sharp shear-die tooling — this is FR-2's whole reason to exist; drill/rout with carbide, extract the abrasive paper dust and never plate the holes.
Can FR-2 CCL-1S-18 be welded?
Not weldable — thermoset laminate; join mechanically with rivets, eyelets or screws, or bond with epoxy/cyanoacrylate.
What surface finishes work on FR-2 CCL-1S-18?
Copper is protected by HASL, OSP or roller-tinning; edges seal well with lacquer or conformal coat to limit moisture wicking into the paper core.
Can FR-2 CCL-1S-18 be formed, bent or molded?
Supplied fully cured and flat; cannot be post-formed or bent — design as flat blanks only, and bake before soldering if stored in humid conditions.
What is the maximum service temperature of FR-2 CCL-1S-18?
FR-2 CCL-1S-18 is rated for continuous use to about 105°C (221 °F), and briefly to 260°C. Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
Sources
- ASTM D709 Standard Specification for Laminated Thermosetting Materials (Grade FR-2) — ASTM International (2017)
- NEMA LI 1 Industrial Laminated Thermosetting Products — NEMA (1998)
- IPC-4101 Specification for Base Materials for Rigid and Multilayer Printed Boards — IPC (2021)
- Engineered Materials Handbook Vol. 2 — Engineering Plastics (laminates section) — ASM International (1988)
- Paper-phenolic copper-clad laminate (FR-2 / XPC) technical data — Kingboard / Nan Ya Plastics / (2023)
- UL 796 / UL 746E Yellow Card listings for FR-2 copper-clad laminates — UL Solutions (2023)
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.