CEM-1 HF
Grade
HF = halogen-free flame-retardant CEM-1
Use where RoHS-plus/halogen-free (Br+Cl < 900 ppm each) customer specs apply, e.g. EU consumer and lighting products.
Values for the HF condition
Other CEM-1 grades and fills
CEM-1 is listed in 3 conditions; see the grade overview at CEM-1.
Compare all 3 grades and fillsHide
| Grade · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness |
|---|---|---|---|---|---|
Punching grade | Pick for high-volume single-sided boards blanked and hole-punched at 40–70 °C instead of drilled and routed. | — | 130 | 2 | 88 Shore D |
HFThis page Halogen-free flame-retardant CEM-1 | Use where RoHS-plus/halogen-free (Br+Cl < 900 ppm each) customer specs apply, e.g. EU consumer and lighting products. | — | 140 | 1.4 | 90 Shore D |
FR-V0Default Standard brominated flame-retardant CEM-1 laminate | Default economical single-sided PCB substrate; pick when cost and punchability matter more than multilayer capability. | — | 145 | 1.5 | 90 Shore D |
What is CEM-1 HF?
CEM-1 HF is CEM-1 in the HF grade — use where RoHS-plus/halogen-free (Br+Cl < 900 ppm each) customer specs apply, e.g. EU consumer and lighting products. CEM-1 HF has a tensile strength of 140 MPa (20.3 ksi), weaker than 58% of composite grades. Elongation at break is 1.4% and the elastic modulus is 14.5 GPa (2.1 Msi). CEM-1 HF has a density of 1.6 g/cm³ (0.0578 lb/in³), lighter than 53% of composite grades. Its glass-transition temperature is 135°C (275 °F). FR-V0 is the default condition FabDigit quotes; HF is available on request or by drawing note.
Limitations
- Hard to polish — 20/100, worse than 90% of composite grades
- Limited service temperature — 110°C (230 °F), worse than 87% of composite grades
- Low fracture toughness — 2.4 MPa·√m (2.18 ksi·√in), worse than 83% of composite grades
CEM-1 HF properties
Typical room-temperature values for CEM-1 HF; 20 are specific to this condition. Other listed values are CEM-1 reference data and may not represent this condition. Bars are the position among composite grades.
Physical4
CEM-1 HF has a density of 1.6 g/cm³ (0.0578 lb/in³), lighter than 53% of composite grades. Its glass-transition temperature is 135°C (275 °F).
Mechanical12
CEM-1 HF has a tensile strength of 140 MPa (20.3 ksi), weaker than 58% of composite grades. Elongation at break is 1.4% and the elastic modulus is 14.5 GPa (2.1 Msi).
Thermal8
CEM-1 HF is rated for continuous service to 110°C (230 °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 17 µm/m·K (9.44 µin/in·°F).
Electrical7
CEM-1 HF is an electrical insulator with a dielectric strength of 30 kV/mm (762 V/mil) and a resistivity of 1×10¹¹ Ω·m.
Chemical & Environmental3
Corrosion resistance is very good (70/100), worse than 64% of composite grades. UV resistance is poor.
Sustainability4
Producing a kilogram of CEM-1 HF takes about 95 MJ of energy and emits 5.5 kg of CO₂ — less than 72% of composite grades. Typical recycled content is 0%.
Manufacturability2
CEM-1 HF's machinability is good (58/100, better than 72% of composite grades).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with CEM-1 HF
Is CEM-1 easy to machine?
Hot-punch (40–70 °C) for blanks and holes, or use carbide/diamond-coat drills and routers at high rpm with vacuum extraction — glass skins are abrasive and the paper core generates dust.
Can CEM-1 be welded?
Not weldable — thermoset laminate; join mechanically or with epoxy/acrylic adhesives.
Can CEM-1 be formed, bent or molded?
Supplied as fully cured flat sheet; no post-forming possible, only cutting, punching, scoring (V-cut) and drilling.
What surface finishes work on CEM-1?
Copper is etched then HASL/OSP/immersion-tin finished; seal cut edges with solder mask or conformal coating to keep moisture out of the paper core.
CEM-1 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 |
|---|---|---|
| epoxy resin (FR, brominated)matrix, includes flame retardant | 32 – 45 | 38 |
| cellulose paper corebleached kraft/cotton-linter paper core plies | 25 – 40 | 32 |
| E-glass woven clothone ply each face (7628/2116 style) | 20 – 32 | 26 |
| bromine (as FR additive)omitted in halogen-free grade | 2 – 6 | 4 |
CEM-1 HF — frequently asked
What is CEM-1 HF used for?
CEM-1 HF is typically used for single-sided PCB substrates, consumer electronics boards and low-cost mechanical/electrical panels. In short: cheapest single-sided PCB base; punchable paper-core laminate; below FR-4 in performance.
What is the tensile strength of CEM-1 HF?
CEM-1 HF has a typical tensile strength of 140 MPa (20.3 ksi) — weaker than 58% of composite grades. Strength varies by condition: see the 3 listed tempers.
Is CEM-1 HF easy to machine?
Reasonably — machinability is rated good (58/100, better than 72% of composite grades). Hot-punch (40–70 °C) for blanks and holes, or use carbide/diamond-coat drills and routers at high rpm with vacuum extraction — glass skins are abrasive and the paper core generates dust.
Can CEM-1 HF be welded?
Not weldable — thermoset laminate; join mechanically or with epoxy/acrylic adhesives.
What surface finishes work on CEM-1 HF?
Copper is etched then HASL/OSP/immersion-tin finished; seal cut edges with solder mask or conformal coating to keep moisture out of the paper core.
Can CEM-1 HF be formed, bent or molded?
Supplied as fully cured flat sheet; no post-forming possible, only cutting, punching, scoring (V-cut) and drilling.
What is the maximum service temperature of CEM-1 HF?
CEM-1 HF is rated for continuous use to about 110°C (230 °F), and briefly to 260°C. Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
Sources
- NEMA LI 1 — Industrial Laminated Thermosetting Products — NEMA (1998)
- IPC-4101 — Specification for Base Materials for Rigid and Multilayer Printed Boards — IPC (2021)
- UL Yellow Card data for CEM-1 copper-clad laminates (ANSI/UL 94, RTI) — 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.